INTEGRATED WATER RESOURCES MANAGEMENT

Transcription

1

2 DEPARTMENT OF WATER AFFAIRS AND FORESTRY INTEGRATED WATER RESOURCES MANAGEMENT GUIDELINES FOR GROUNDWATER MANAGEMENT IN WATER MANAGEMENT AREAS, SOUTH AFRICA INTEGRATED WATER RESOURCE MANAGEMENT STRATEGIES, GUIDELINES AND PILOT IMPLEMENTATION IN THREE WATER MANAGEMENT AREAS, SOUTH AFRICA DANIDA FUNDING AGENCY Edition 1 March 2004

3 TITLE: GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT IN WATER MANAGEMENT AREAS, SOUTH AFRICA: VOLUME 2 FUNDING AGENCY: DANIDA CATEGORY: Guideline PURPOSE: To provide guidelines for integration of coordinated groundwater management into IWRM at different levels of resource managers within Catchment Management Agencies. TARGET GROUP: DWAF, IWRM Project Consultants and Resource Managers in three Water Management Areas. DATE: March 2004 STATUS: Edition 1 ENQUIRIES: Department of Water Affairs and Forestry Private Bag X 313 Pretoria 0001 Republic of South Africa Tel: (012) / Fax: (012) / qma@dwaf.pwv.gov.za Website:

4 DOCUMENT INDEX DOCUMENTS FOR OUTPUT 7: STRATEGIES, TOOLS AND SYSTEMS APPLIED WITHIN THE THREE SELECTED WMAS TO ACHIEVE SUSTAINABLE GROUNDWATER DEVELOPMENT AS AN INTEGRAL PART OF IWRM: 1. a. Groundwater Management Strategy for National Water Resource Strategy, DWAF/DANCED, 2001 b. Groundwater Management Strategy: Summary, DWAF/DANCED, 2002 c. Groundwater Management Strategy: Executive Summary, DWAF/DANCED, a. Guidelines for Groundwater Management in Water Management Areas, South Africa, Carl Bro a/s, IZNA Consortium, February 2002, Volume 1 and 2. b. Guidelines for Groundwater Management in Water Management Areas: Summary, South Africa, Carl Bro a/s, IZNA Consortium, February 2002 c. Guidelines for Groundwater Management in Water Management Areas: Executive Summary, South Africa, Carl Bro a/s, IZNA Consortium, February 2002 RELATED DOCUMENTS: First Edition National Water Resource Strategy, DWAF 2002 Integrated Water Resources Management Communication Strategy, DWAF Generic Communication Strategy for IWRM, DWAF/DANCED, December Institutional Roles and Linkages: Phase 1 Report, Carl Bro a/s, IZNA Consortium, February Guidelines for Stakeholder Participation in Integrated Water Resources Management in Water Management Areas in South Africa, Carl Bro a/s, March Evaluation of the involvement of Previously Disadvantaged Individuals in the Catchment Management Agency establishment process the three Water Management Areas, date. Capacity Building Overview Assessment Vol.1, Carl Bro a/s, IZNA Consortium, October Capacity Building Overview Assessment Vol.2, Specific Capacity Building Requirements of Role-Players, Carl Bro a/s, IZNA Consortium, October Capacity Building Implementation Plan, Carl Bro a/s, IZNA Consortium, April 2002 Guideline on the Viability Study for the Establishment of a Catchment Management Agency, Carl Bro a/s, Pegasus Strategic Management, February GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE i

5 TABLE OF CONTENTS VOLUME 2 TABLE OF CONTENTS PAGE DOCUMENT INDEX I CHAPTER 1: GROUNDWATER RESOURCE ASSESSMENT AND SITUATION ANALYSIS 1 Executive Summary Introduction Steps in Resource Assessment Developing a Conceptual Model Initial and Conceptual Planning Hydrocensus Water Balance Elements in the Water Balance Equation Data Requirements for Resource Assessment Detailed Planning and Reconnaissance Procedure Exploration Drilling Aquifer Characterisation Aquifer Tests Planning and Performing of Pumping Tests Downhole Geophysics Methods Tracer Tests Recharge Estimation Discharge Estimation Numerical Groundwater Modelling Environmental Considerations Strategic Environmental Assessment SEA Analysis of Opportunities and Constraints References 29 CHAPTER 2: GROUNDWATER RESOURCE ALLOCATION 30 Executive Summary Introdcution How to Reconcile Sustainability, Equity and Efficiency with Groundwater Quality Sustainability Sustainability Indicators Equity Efficiency Recognising the Strategic Benefits and Values of Groundwater How to Provide the Technical and Scientific Information for Stakeholders To Establish a Fair and Equal Allocation Process 43 GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE ii

6 TABLE OF CONTENTS 2.5 How Groundwater can Become Part of the Mainstream Water Service / Water Supply Activities and Development Available Groundwater Resources Allocatable Groundwater Resources References 50 CHAPTER 3: GROUNDWATER MANAGEMENT AND PROTECTION APPROACHES 52 Executive Summary Introduction Principles of Water Resources Management in South Africa Principles Underlying Water Resources Management Resource Management Principles Implementation of Resource Directed Measures Prioritisation and Implementation of Source Directed Controls Guidelines for Wellhead Protection Minimum Borehole Construction Standards Wellhead Protection Zones Remediation Strategies Water Quality Standards Variations in Quality Levels of Standard The Reasons for Assessing Water Quality Standards South African Water Quality Standards Natural Groundwater Qualities 90 Appendix A References 100 CHAPTER 4: GROUNDWATER MONITORING AND INTEGRATED MONITORING NETWORKS 101 Executive Summary Introduction: Role-Players in Groundwater Monitoring DWAF Responsibilities A Tiered Approach to Monitoring: Other Stakeholder Responsibilities CMA Responsibilities Risk-Based, Cost-Effective Monitoring Strategies Guiding Principles Monitoring Objectives (The Need for Groundwater Monitoring) Risk-Based Approach Iterative Approach Overcoming Resource Limitations Designing a Catchment (Level 2) Monitoring System Designing a Local Monitoring Network (Level 3) Monitoring Groundwater Use Selection of Monitoring Sites and Data Collection Monitoring Networks Monitoring Borehole Design and Construction Monitoring Point Density 128 GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE iii

7 TABLE OF CONTENTS Frequency of Measurement Data to be Collected A Step by Step Approach to Groundwater Sampling and Monitoring Integration of Groundwater monitoring with other Monitoring Networks, Especially Surface Water and Hydro-Meteorological Monitoring A 5-Year Resource Quality Monitoring Plan References 147 CHAPTER 5: GROUNDWATER INFORMATION SYSTEMS FOR IWRM 149 Executive Summary Introduction The Type of Queries that a Geohydrological Information System should be Able to Address Reasons for Data Collection Relevant and Associated IWRM Information Systems Water Situation Assessment Model (WSAM) Water Resource Monitoring and Assessment Information System (WRMAIS) Water Management System (WMS) Hydrological Information System (HIS/HydSys) National Groundwater Archive (NGA) Water Use Authorisation and Registration Management System (WARMS) Information System Architecture Information Distribution Mechanisms Data Types and Frequency of Collection Data Collection Methods Data Verification, Data Quality, Confidence Limits, Data Analysis and Metdata Potential Information System Constraints Information System Outputs Recommedations References 175 GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE iv

8 EXECUTIVE SUMMARY VOLUME 2 CHAPTER 1 GROUNDWATER RESOURCE ASSESSMENT AND SITUATION ANALYSIS EXECUTIVE SUMMARY Expected context The development of CMAs offers an opportunity for integrated assessment and optimal use of water resources. It is hoped that investigation of groundwater potential in the WMAs will result in an appreciation of the strategic value of groundwater and will encourage improved investment in groundwater feasibility studies. In this scenario, the Groundwater Coordinator will need to develop a sound understanding of the aquifer potential of the WMA, and will be provided with the resources necessary to determine, with reasonable confidence, the volumes of allocatable groundwater available on a sustainable basis. The role of the Groundwater Co-ordinator It is likely that most of the CMAs will appoint someone to specifically handle and coordinate the groundwater component of its water resources management function. The specialised nature of groundwater management means that such a person must be a trained hydrogeologist. The Groundwater Coordinator will need to act as a central point of understanding in balancing the predicted potential for groundwater delivery against the demands of water users. The Coordinator will need to commission and coordinate resource investigations, many of which will be undertaken by specialist consultants. It is the role of the coordinator to ensure that best practices are followed in these investigations and that the most appropriate and cost effective tools and technologies are employed. A phased approach is generally used, as described in this chapter. The groundwater resources in many catchments remain undefined in terms of the water balance, and its role in the larger water cycle and environment. Tools for assessing these components of the resource are described. Where the location and extent of the groundwater resource remains undefined, groundwater exploration and aquifer characterisation is required. An overview of the tools and methods for exploration and aquifer characterisation is given. At the end of a groundwater resource assessment the Groundwater Coordinator must ensure that the catchment manager/stakeholders/etc understand the basic functioning of groundwater in the catchment and the sustainable yield of the resource. The Groundwater Coordinator needs to ensure that investigation results are captured and stored in the current WMA and national databases. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 1

9 EXECUTIVE SUMMARY The Groundwater Coordinator is directed through exploration best practice at a level of detail that should help to manage and commission appropriate projects. Available tools and sources of more detailed information are given. Particular emphasis is given to the assessment of fractured aquifer yields and reference made to recent work by the WRC. Resource Assessment Phases The following diagram illustrates the phases that would typically be expected of a groundwater resources assessment study: Demand for new resources/impacted current resources Situational Assessment Desktop study Review of Literature & data bases (e.g. NGDB) Reconnaissance/ Target Identification Field Assessment (Remote Sensing, Geological mapping, Hydrocensus, and Geophysics) Target Appraisal Geophysics, Drilling, Pumping tests Recharge Estimation. Aquifer assessment Monitoring Cost-benefit comparison of water sources Resource Selection Sustainable Resource Development The final decision on the development of a groundwater resource is generally a comparative one, assessing the costs and benefits of groundwater development against those for other available water sources. Key criteria are identified on which these decisions are often made are described and some typical issues for different sources listed. The groundwater coordinator needs to understand how these decisions are taken so that they can fully represent the opportunities and constraints presented by aquifer development. Key Recommendations The investigation of aquifer potential is the core of hydrogeological science and much of a hydrogeologists formal training is focussed on this technical area. If we hope to be able to make full assessments of available groundwater resources around the country we will need more of the same in terms of strong hydrogeological expertise, mainly in the consulting field, and a significant increase in geophysical capacity. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 2

10 EXECUTIVE SUMMARY An area where improved approaches and capacity is required is in recharge estimation, which will be critical for sustainable yield determination. We need to improve the accuracy of recharge estimation around the country and in a greater variety of hydrogeological settings. An area where most hydrogeologists need additional training and exposure is in cost-benefit comparisons of groundwater with other water sources. Hydrogeologists need to be able to understand and speak the language of resource planners in order to articulate the benefits of groundwater development, as well as understand the long-term socio-economic constraints. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 3

11 INTRODUCTION 1.1 INTRODUCTION General The extent of groundwater resources can be complex to assess and difficult for nonspecialists to picture. As a result groundwater resources have often been neglected in the assessment of regional water resources. The National Water Act requires water managers to consider all the water resources of a region. This has coincided with the recognition of groundwater s ecological functions and its valuable role in rural supply, drought relief and supply security. Aims This chapter aims to help water managers in CMAs to assess the groundwater resources of their region and to plan with a full appreciation of their value and the close connection to surface water resources. Document Content The aim above is tried achieved through a description of the various steps in a groundwater resource assessment, suggestions for data collection and discussions of strengths and weaknesses in various methods. Tools for the assessment of aquifers at both the regional and local levels are briefly described and discussed. The information required for water managers to develop a holistic appreciation of the groundwater resources of a region is listed, as well as its place in water balance models. Tools for the development and assessment of aquifers are discussed in terms of their application, what they measure, and the steps required for their application and use. An appreciation of the dynamics of hydraulic systems and the role of integration of groundwater with other sources of supply is vital if the exploitation of groundwater resources is to be sustainable. The subjects of reuse and the conservation of water are discussed in Chapter #X of this document. This chapter will also provide a perspective on the determination of recharge and its role in the sustainable exploitation of groundwater resources. Approach It should be noted that the generic nature of this document means that a lot of the information contained here is of a general nature. The most appropriate strategy should be determined by case specific circumstances, including available budget, water quality, variations, and the location of recharge and discharge areas. Integration It is important to recognise that groundwater resource assessment is part of assessing the total water resources of the catchment. The results of groundwater resource assessment should thus be integrated with the results of surface water resources studies. Care should always be taken that double accounting does not take place where groundwater supplies baseflow to surface water. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 4

12 STEPS IN RESOURCE ASSESSMENT 1.2 STEPS IN RESOURCE ASSESSMENT The following steps are necessary to assess groundwater resources in an area. The steps to be followed will depend on the extent to which the resources have already been studied and developed. Where no development of the resources has taken place, the assessment will follow the steps from one to Initial/Conceptual Planning: This includes the understanding of the situation, water requirements and description of possible development scenarios. Existing knowledge is used to develop a conceptual understanding of the groundwater system. 2. Water Balance calculation: Develop conceptual model to illustrate the interactions of groundwater and surface water resources in the relevant catchment. Then a water balance equation is set up based on the conceptual model and available data. This requires a good understanding of inflows (recharge) and outflows (discharge) to and from the system. Provided that sufficient data is available, the conceptual model should be supported by a simple numerical model. 3. Detailed Planning and Reconnaissance: Based on the conceptual understanding of the system and the water balance, more detailed planning and field reconnaissance are done to verify the results and interpretations. 4. Characterisation of the Aquifer: Use tests, geophysics and tracer tests to determine the aquifer characteristics. Also assess water quality through hydro census and analysis. At this stage a comprehensive numerical model may be possible and useful. 5. Strategic Environmental Assessment: The results of the Resource assessment should form part of the regional scale planning process. Decisions on the development of the groundwater resource should be done with due consideration of physical, environmental, economic and social factors. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 5

13 DEVELOPING A CONCEPTUAL MODEL 1.3 DEVELOPING A CONCEPTUAL MODEL A conceptual model is a descriptive or pictorial representation of a regional water system, including the dimensions of the system, its functioning, flow and recharge. Existing data and expert knowledge provide sufficient information in most areas for the construction of a conceptual model. The first step in the development of the conceptual model involves a description in terms of the geological and hydrographic units in the area, the types of aquifers, their interconnectedness with each other and surface water sources, and the boundaries of the system. Existing reports, maps and first hand experience may provide sufficient insight for the groundwater system to be described to a reasonable level of accuracy. The next step is a description of the existing flow systems. This may require information and a description on geomorphology, hydrological data, precipitation, evapotranspiration, runoff, groundwater head data, probable areas of groundwater recharge and discharge, and geochemical data. A preliminary water budget for the area should also be calculated. This includes a quantitative description of the inputs and outputs to the system, including both natural and anthropogenic inputs. The water budget should include estimates on the magnitudes of flows and possible changes in storage. The conceptual model provides the foundation for developing a detailed plan for the resource assessment study and should describe the initial understanding of the hydrological system. It should identify the areas most suited for exploration, give an indication of the yields that may be expected and its quality and help to select the most appropriate tools to use during the more detailed study. The conceptual model will define the needs for further data as the study continues and as more data becomes available this understanding will broaden and refine Initial and Conceptual Planning Assessing the resource Groundwater Exploration Where new groundwater resources are explored, an assessment of potential sustainable yield and pilot abstraction will be needed. However, in many cases some exploitation or monitoring has already been completed. In that case, a consolidation of the available data will be needed. The need for the water source to be located reasonably close to the settlement that requires supply tends to limit the area of exploration. Most South African aquifers are of a deep nature, occurring under confined or semi confined conditions. This means that in most cases, defining the aquifer geometry equates to the location of aquifers. Phases of Exploration and Assessment Exploration can be divided into a number of interlinked and sequential stages, which involve increasing expenditure and knowledge and decreasing risk. The early phases are known as the planning and reconnaissance phases. These phases cover the stages leading to the selection of an area for detailed ground work. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 6

14 DEVELOPING A CONCEPTUAL MODEL The first two steps of the exploration study are the conceptual and detailed planning phases. These phases cover the review of existing literature, maps and aerial photographs, and the selection of an appropriate exploration technique and strategy. The next phase in the exploration project is the reconnaissance phase, which involves the gathering and interpretation of focussed field data, and culminates in the selection of exploration drill sites. This is followed by the target appraisal phase where various methods including detailed geophysics are used to pinpoint the drilling target. After a successful target-drilling programme follows aquifer assessment. The boreholes are test pumped, results are interpreted and the capacity is calculated. Water chemistry is checked to establish if the water is suitable e.g. for drinking water. After aquifer assessment and successful exploration drilling follows the development phase, which includes the construction of the production boreholes and the installation of the pumping and distribution infrastructure. Following this is the production phase where the water resources are put to use. The final phase is the monitoring of the groundwater resource, which include background monitoring, flow path monitoring and impact monitoring. Completion of this phase results in the evaluation of the monitoring data, reporting to the relevant authorities and necessary actions or changes in the management plan if needed. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 7

15 DEVELOPING A CONCEPTUAL MODEL Figure 1 illustrates the different phases of the groundwater exploration study, with the relative expenditure required during each phase. The figure also illustrates the time at which decisions on the continuation of the study should be made. Expenditure Logarithmic Scale Key Decision node Rate of expenditure High Risk Regional Selection Area Selection Decreasing Risk Formation Suitability Feasibility Conceptual Planning Detailed Planning Reconnaissance Phase Target Appraisal Aquifer Assessment Development Decommissioning Activity Literature review, and Discussion with Peers Literature review, field visit Remote sensing, Hydro-census, Geophysics. Detailed geophysics, Geological mapping verification. Drilling, Test Pumping, Chemical sampling and analysis Borehole construction, pump installation, Supply infrastructure Removal of equipment and closure of boreholes. Monitoring starts. FIGURE 1: STAGES OF A GROUNDWATER EXPLORATION PROJECT (MODIFIED FROM MOON AND WHATELEY, 1995) GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 8

16 DEVELOPING A CONCEPTUAL MODEL Constraints The planning of an exploration programme needs to identify and account for various constraints, which may include: Quantity and quality of water required Preferred sources of supply Location of the demand Resources available to assess and develop a source Environmental considerations Tools If it is expected that groundwater can supply the quantity and quality of water required in a feasible location, planning for resource development needs to take into account the local geological conditions. An understanding of the hydrogeological terrains will direct the exploitation, assessment and interpretation methods, which are suitable. The planning process for an exploration programme needs to include the relevant professionals who can take account of the acceptable spending and risk for the project. Information All available information on the study area should be reviewed. This may include: Borehole logs Maps, including topo-cadastral, geology and geophysical maps Reports Rainfall Test-pumping data Water quality data Water levels Even information on dry boreholes can provide invaluable information about drilling targets (DWAF, 1997). The data should then be used in a preliminary groundwater resource assessment to define the areas or zones of potential groundwater occurrence that will be investigated further. If geophysics are to be used during the exploration phase it must be established at this stage and the appropriate techniques defined. This should be conducted by a hydrogeologist and a geophysicist in cooperation. Hydrogeological terrains A number of distinct hydrogeological terrains exist in South Africa. The tools used in the groundwater exploration programme should be selected based on the hydrogeological characteristics of the exploration area. A description of the South African hydrogeological terrains is presented in level 4 of this guideline. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 9

17 HYDROCENSUS 1.4 HYDROCENSUS Background Existing and historical database data rarely provide adequate information on the distribution of water sources and the water quality within an area. In the design of a resource development programme, it is often valuable to gather additional information from users of aquifers and surface water bodies. The design and execution of a programme that collects field data in order to develop a more complete understanding of the hydrological systems within a study area is known as a hydrocensus. An example of a hydrocensus questionnaire/ data sheet is given in Level 4 of these guidelines. In groundwater studies this generally involves the collection of data on groundwater levels, chemistry, and use. During the hydrocensus it may also be important to record the interactions between groundwater and surface water. A risk-based approach can be followed to identify the type of data that should be collected. The information needs that will be addressed through the hydrocensus could be established by asking simple quesitons, like: Why do we need data? How will we obtain this data? What must the data represent? How will we use the data? The process ensures that the data collected for decision-making are of the right type, quantity, and quality. The following steps are usually part of a hydrocensus: Step 1: State the Problem Step 2: Identify Inputs Step 3: Define the Boundaries of the Study Area The description should include study objectives, the regulatory context, groups who are involved or who have an interest in the study, political issues, funding, previous study results, and any obvious sampling constraints. The next step is to identify the different types of information needed to resolve the problem. Data from previous studies or investigations may be available, or new data may need to be collected. The spatial and temporal boundaries of the study area are defined and the data collection process placed within this context. Factors such as seasonal or daily variations, as well as weather and temperature conditions that may affect the data collected must be considered. Identification of obstacles to data collection, such as access to private property and the availability of sampling equipment and personnel. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 10

18 HYDROCENSUS Step 4: Develop action plan Proper planning can save time and expense when things go wrong in the field. Important points to note before embarking on the field data gathering are: That practical arrangements have been made for analysis of the water or soil samples. That access to the measuring/sampling points has been arranged with the proper authorities or landowners. That the necessary field equipment is available, and in working order. A checklist of necessary equipment can be very helpful and may eliminate the likelihood of finding yourself in the field without the right equipment. An example of such a list is given in Appendix D#. That transport and accommodation has been arranged, and that arrangements have been made for the samples that are collected to be returned to the lab for analysis, or a place of storage. Step 5: Collect Field Data A decision has already been made on what data needs to be collected (Step 2) and the area over which the data is to be collected geography and time (Step 4). The parameters that will be measured vary depending on conditions prevailing at specific sites as well as the type of data needed to develop a model or for monitoring. Step 6: Collation, Manipulation and Analysis of Data When the data have been collected and the results of the sample analysis received, they need to be entered into a database. Once in the database the data can be transformed, manipulated and presented in various forms. Geographically referencing the data and mapping then usually proves valuable in the interpretation of the data. The hydrocensus report shall include the operational details and theoretical assumptions of the sampling and analysis plan. This is necessary for the following statistical interpretation of the data. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 11

19 WATER BALANCE 1.5 WATER BALANCE The National Water Act recognises the hydrological cycle and the integrated nature of water resources. As such the management of groundwater needs to be integrated with the management of all other water resources. The management of groundwater entails assessing and controlling the degree of fluctuation that can be tolerated in an aquifer to ensure that water levels remain above a critical level, below which further pumping could cause harmful and often irreversible effects (Bredenkamp, et al., 1995). Significant in the management of groundwater resources is the recognition of groundwater s function in maintaining the ecological reserve. The use of water balance models offers a means of integrating the management of groundwater and other water resources in this way addressing the mis-accounting and mis-allocation of water resources. Water balance approaches are based on the principle of the conservation of mass. The inputs: precipitation; groundwater; surface water inflows - equals the outputs: evapotranspiration, groundwater and surface water outflow - plus the change in storage. Inputs = Outputs+ S FIGURE 2: AN ILLUSTRATION OF THE WATER CYCLE, SHOWING THE MAJOR COMPONENTS THAT SHOULD BE CONSIDERED IN WATER BALANCE MODELS. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 12

20 WATER BALANCE The water budget for a basin can be stated as: P + Q on = ET + Q off + S Where P = precipitation Q on = water flow onto the site (sum of surface flow, interflow and groundwater flow) Q off = water flow off the site (sum of surface flow, interflow and groundwa ter flow) ET = evapotranspiration S = change in water storage All components are given as rates, eg. Mm /day or mm/year Rewriting the water budget to incorporate subcomponents like water storage in snow, surface water reservoirs, the unsaturated zone and the saturated zone results in the following equation which gives recharge as result: R = Q off gw Q on gw + Q bf + ET gw + S gw Where R = recharge to groundwater Q bf = groundwater discharge to streams or springs The recharge component of the water balance is essential and gives a very good indication of how much water gets into the system and might be available for allocation. Various methods for the water balance calculation exist in the literature, and this is just one example Elements in the Water balance equation Groundwater in the hydrological cycle Recharge characteristics The management of a groundwater resource must take place within the recognised context of groundwater s role in the hydrological cycle. Exploited aquifer systems need to be managed in such a way that exploitation can be sustained over an extended period, and that associated effects are within acceptable limits. The impacts of exploitation will include a reduction in the overall discharge from the groundwater unit, possibly a decrease in overall storage and likely an increase in overall recharge. Effective recharge to an area can be highly variable, in time and space. Such variations may be overlooked when using an average annual value for effective recharge. It is likely that the water balance approach will require adjustment, to account for drought cycles over periods of several years. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 13

21 WATER BALANCE Integration with surface water management Water quality issues Storage / groundwater mining The new Water Act requires water managers to consider groundwater as part of the larger hydrologic cycle, in a continual interaction with surface water. It is therefore essential that any groundwater planning method fits with local surface water strategies, ensuring the two linked resources can be conjunctively used in a pragmatic manner, minimising adverse impacts on the overall water resource. The Resource Directed Measures and the Reserve encompasses quality as well as quantity issues. Water quality and quantity are inextricably linked factors and it is possible that quality thresholds could be surpassed prior to quantity thresholds. It will therefore often be necessary to adjust the quantitative resource assessment to account for water quality issues, to ensure that the resource is of an acceptable standard with respect to both criteria. Part of the groundwater within a region may be identified as neither entering nor leaving the aquifer. Such groundwater could be considered as being held in storage. If abstraction is possible, without impacting upon the surface environment, this additional volume of groundwater could be used and, subsequently, included in the available resource of an area. However, care must be employed to ensure that this valuable back-up resource is not degraded over the long term Data Requirements for Resource Assessment The following Table summarises the kinds of data that are typically required for groundwater resource assessments. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 14

22 WATER BALANCE TABLE 1: INFORMATION TYPICALLY REQUIRED, AS PART OF A RESOURCE ASSESSMENT/SITUATIONAL ANALYSIS PROGRAMME Category Information Source Topographic maps* Surveyor General Surface features Aerial photographs Surveyor General Satellite imagery Surveyor General, CSIR, NASA Geological maps* Geological Survey Existing reports* DWAF, Consultants, Gov. Departments Geology and Structure Piezometry Recharge Discharge Aquifer Properties Aerial photos Satellite imagery Field geological mapping Geophysical surveys Lithological and geophysical borehole logs Water level measurements in observation boreholes and nonpumped wells* Rainfall records* Meteorological data* (evaporation, sunshine, wind, humidity) Land-use and vegetation Soil type and hydraulic properties* Leakage losses from water supply Irrigation return flow (from crop type, soils, agricultural practices, climate, irrigation techniques) Sewage leakage flows (from population, water use, recorded sewer flow) Pumped abstraction* (from flowmeter records, abstraction returns, pump capacity, hour/fuel consumption) Spring flows* Flow in drains and sewers Interpretation of peizometric gradients* Calculation of water balances* Interpretation of pumping test data Surveyor General Surveyor General, CSIR, NASA Field Reconnaissance Phase Target Appraisal Phase Aquifer Assessment Phase Aquifer Assessment Phase DWAF, Weather Bureau Weather Bureau, ARC Satelite imagery, Topographic Maps Local Authority ARC, Dept. Agriculture Local Authority DWAF, WUA DWAF Local Authority Aquifer Assessment Phase GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 15

23 WATER BALANCE Category Information Source Interaction with surface water Estimates for Transmissivity and Storage Coefficient* Tracer Tests Flow, fluid conductivity and temperature logs Interpretation of well hydrographs Laboratory measurements on cores Losses/gains to or from streams* Water levels in lakes or rivers* Rating curves to convert levels to flows Lithologies and inferred hydraulic properties of bed material Aquifer Assessment Phase Aquifer Assessment Phase RDM determination DWAF Council for Geoscience Items marked with * are considered essential in most resource assessments GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 16

24 1.6 DETAILED PLANNING AND RECONNAISSANCE DETAILED PLANNING AND RECONNAISSANCE Desktop study (Including airborne geophysical data) Target zone identification Field reconnaissance (Viability of geophysical methods) Pilot field-testing (Initial reconnaissance geophysics) Detailed surface geophysics (To select optimal drilling locations) Geophysical logging (Aquifer characterisation and refine exploration programme) FIGURE 3: STEPS TYPICAL OF A GROUNDWATER EXPLORATION PROGRAMME, WITH SPECIAL EMPHASIS ON THE USE OF GEOPHYSICS Procedure Following from the conceptual planning, areas for further investigation are delineated and more detailed information gathered. Such information may include airborne geophysics, remote sensing and aerial photography data and hydrocensus/database information. The insight and experience of hydrogeologists who have previously worked on groundwater problems in the study area will provide essential insight and detail, and should be consulted. The regional offices of the Department of Water Affairs and Forestry can be a valuable reference point. It is important to note that airborne and regional data often lack resolution due to the scale of survey. It should always be considered that the regional anomaly could result from a number of smaller anomalies on the surface. These target areas should be mapped on a base map. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 17

25 DETAILED PLANNING AND RECONNAISSANCE Exploration Drilling Most groundwater investigations involve the drilling of one or more exploration wells before the construction of production wells is begun. The information gained from exploration wells can be used for the following general purposes: Regional groundwater assessment study Design and construction of one or more production wells at a particular site Where no or poor targets are identified the exploration borehole may be preserved for monitoring purposes. During water resources studies features of likely groundwater occurrence are defined and locations with a high probability of intersecting the target water body are pinpointed for drilling. The presence of water and the quality of that occurrence can only established through the drilling of a borehole. It is important for the results of the exploration drilling to be carefully recorded by a qualified geotechnician or geologist. Among the more important things to note is the geology and mineralogy of the formations being drilled. This is done by collecting drill samples at regular intervals, usually at one meter depth intervals. Notes should also be made on depth to any water strikes, the size of the water strike and its quality. If an air drilling system is being used, the blow yield should be noted. Variations in water quality can provide valuable information on the interaction and mixing of different structures or formations. The information gathered during the drilling is usually summarised in a lithological log (see example in Level 4). Consultation with the drilling operator will help in compiling an accurate and informative log. The drilling action and penetration rate provide valuable information on the formation being drilled. As a supplement to the lithological log a drilling-time log that records the amount of time required to drill a certain distance may also be compiled. The drillingtime log is constructed as a curve or diagram showing penetration for each length of drill rod, with significant changes in drilling rate indicating that a different formation is being drilled. The logs can then be used to correlate the results of the geophysics exploration programme. To minimise the cost every one of the drill locations should be re-evaluated as more information becomes available during the drilling programme. A number of drilling techniques are available and in common use in South Africa. These are described further in Level 4 The drilling method selected will depend on the geological terrain, the depth of the target and the budget available. It is common to use more than one technique where the target structure or formation occurs at depth. For example the mud rotary drilling method may be used to drill through unconsolidated or badly weathered deposits, and the air rotary method to drill through the harder formations. A large number of drilling operators are active in South Africa. Most of them are affiliated to either the Borehole Water Association of South Africa or the Drilling Contractors Association of South Africa. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 18

26 AQUIFER CHARACTERISATION 1.7 AQUIFER CHARACTERISATION Once an aquifer has been located, it needs to be assessed for its ability to supply water. This requires the determination of the aquifer s hydraulic properties. Pumping tests offers direct physical information about the characteristics of aquifers Aquifer Tests Controlled pump testing is a well-established means of assessing aquifer characteristics. Aquifer tests, eg, pumping tests, are the only method that provide simultaneous information on the hydraulic behaviour of the well, the reservoir and the reservoir boundaries, which are essential for efficient aquifer and wellfield management. These tests are conducted in the field, stressing the aquifer through highly controlled pumping. Such a test involves the pumping of a production well at several fractions of full capacity (the step drawdown test) and at a constant rate (the constant discharge test), with water levels measured at frequent intervals in the production well and nearby observation wells, and sometimes surface water bodies like streams and springs. Time-drawdown and distance drawdown data are analysed with various methods including computerised model equations and type-curve matching. The method used and the interpretation of pumping test data requires an understanding of the aquifer system or systems being pumped. Pumping tests usually have the following as objectives (Van Tonder, et al., 2001): To develop a better understanding of the aquifer system The quantification of its hydraulic characteristics and properties An assessment of both the sustainable yield and efficiency of the borehole The sustainable yield is defined as the discharge rate that will not cause the water level to drop below a prescribed limit, for example the position of a major water strike. It is also important that the total abstraction rates of boreholes situated in an aquifer must not exceed the sustainable yield of the aquifer in total, i.e. the average annual recharge (Van Tonder, et al., 2001) Planning and Performing of Pumping tests Guidelines have been developed by the Water Research Commission for conducting pumping tests under South African conditions (Van Tonder, et al., 2001). The document focuses on the analysis and interpretation of pumping test data from fractured-rock aquifers. Sections of Van Tonder et al. (2001) is reproduced in Level Downhole Geophysics Methods Aquifers can be investigated by using geophysical tools in the borehole. Several geophysical methods have been adapted to provide data such as thickness of different formations, zones of highest porosity, water quality, etc. The commonly used geophysical logging tools available are resistivity, spontaneous potential (SP), gamma, neutron, sonic / acoustic, temperature and calliper logs. The different methods are briefly described in level 4 of the guidelines Tracer Tests A Water Research Commission funded study by Van Wyk, et al. (2001) provides good background to the use of tracer tests in South Africa. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 19

27 AQUIFER CHARACTERISATION Recharge Estimation Pumping test analyses provide most of the information necessary to determine the hydraulic characteristics of aquifers, but it is not possible to calculate the sustainable yield without a reasonable estimation of the amount of recharge that it receives over an extended period. Recharge Processes The principle recharge mechanisms based on their sources have been described by Lerner, et al. (1990). These are: Direct Recharge: This is water added to the groundwater reservoir by direct vertical percolation through the unsaturated zone. Indirect recharge: This is percolation to the water table through the beds of lakes and streams. Localised Recharge: This is an intermediate form of groundwater recharge resulting from the horizontal (near-) surface concentration of water in the absence of well defined channels. Challenges in Estimating Recharge Recharge in arid and semi-arid regions tends to be highly variable. It is thus important to note that under such circumstances water balance calculations done on precipitation data from a single or few years will not reflect actual groundwater recharge. The reason for this the fact that significant infiltration to the groundwater only results from the larger events at infrequent intervals. Thus it is critical to have daily rainfall data to estimate recharge. A further challenge in recharge estimation is the issue of spatial variability. Natural variations in soil type, vegetation, aspect, and others, influence recharge figures over an area and so does human activities. Care should thus be taken when using point observations to estimate the recharge over larger areas. Recharge Methods Qualified estimates A description of the recharge methods adapted to South African conditions is provided by Van Tonder and Xu (2001). Generally, an integrated approach that uses more than one method of recharge calculation is advocated. Qualified estimates on the percentage of recharge in an area are based on the study of existing maps on soil type, geology, vegetation and land-cover. The use of multiple criteria could be used to refine the recharge estimates for an area. The following soil types are used with the assumed recharge percentage on a flat bare area given in brackets (Van Tonder and Xu, 2001) % Clay Soil Type 0 10 Sand (50) Sandy loam (20) Sandy Clay loam (5) > 35 Clayey loam, clay (3) GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 20

28 AQUIFER CHARACTERISATION Depending on the vegetation in the area the following percentage corrections are made to the above percentages: Wood/Tree (90) Grass (40) Bare (0) Geology may be used in a similar manner. In this case the qualified guess is dependent on the percentage of the area covered by a specific type of formation or soil cover and the slope of the topography. Geology % Recharge (Soil cover <5 m) % Recharge (Soil cover >5 m) Sandstone, siltstone mudstone, 5 2 Hard Rock (granite, gneiss, etc.) 7 4 Dolomite 12 8 Calcrete 9 5 Alluvial sand Coastal sand Alluvium 12 8 Coastal sand A correction of 40% should be made if the surface slope is more than 5%. The Chloride method Isotopes This is the cheapest method to estimate recharge. The Cl in rainfall and in the saturated zone must be known as well as the dry deposition of Chloride, which may be a factor in coastal areas. The method is described in detail by Van Tonder and Xu, Oxygen-18 and Deuterium ( 2 H) will fingerprint the origin of the water while the Deuterium displacement method will give an estimate of recharge if the recharge is generally below 20 mm/a (Van Tonder and Xu, 2001). Isotopes are specifically useful to determine the recharge source and the age of the groundwater. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 21

29 AQUIFER CHARACTERISATION Discharge Estimation It is essential to gain a good understanding of the groundwater discharge processes in a catchment in order to balance the estimates of inflows and outflows. Groundwater discharge may occur through any of the following: Abstraction from boreholes; Baseflow to rivers; Baseflow to springs; Baseflow to wetlands; Discharge to the sea; Transpiration from vegetation; Evaporation from the capillary zone. Various methods are available to either directly measure or infer discharge volumes. These are summarised below. Abstraction from boreholes / wells Baseflow May be calculated through: Records of pumped volumes Records of power or diesel consumption Records of the irrigated area, crop types and crop coefficients Records of the number of people & livestock dependent on a source Groundwater fed baseflow to surface water features such as springs, rivers, wetlands and lakes may be calculated from stream hydrographs. This requires the volume of flow in the stream or spring to be measured. The separation of a stream hydrograph into its components is based on the assumption that the different components of flow arrive at the stream at different intervals. Overland flow arrives most rapidly, followed by through-flow and groundwater flow at the slowest rate. Two methods exist to differentiate between baseflow and stormflow, graphical methods and Isotopic/chemical methods. Graphical methods In graphical hydrograph separation an arbitrary separation is made between quick-flow and slow-flow. A widely used approach is described by Hewlett and Hibbert (1967). It must however be noted that hydrometric methods alone fail to adequately explain stream chemistry during storm runoff events. Isotope/Chemical Separation Hydrograph separation using stable environmental isotopes has been widely applied in hydrological process studies (Saayman and Scott, 2002). The basis of this method is temporal variations in the isotopic composition of precipitation, resulting in the isotope composition of the event water differing from the composition of the water already in the catchment (Genereux and Hooper, 1998). GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 22

30 AQUIFER CHARACTERISATION Where hydrograph separation methods are used, the surface hydrograph data needs to be checked against relative groundwater/surface water levels and the occurrence of permeable zone, in order to confirm the feasibility for discharge. Gaining and losing reaches of rivers should be identified as well as areas where the surface and groundwater systems are isolated from each other by impermeable layers. The baseflow separation technique used will depend on the type of data that is available. Xu, et al. (2001) give an assessment of the methods in a Water Research Commission report on the reserve determination, and recommend a modified Herold (1980) approach. Actual measurements of groundwater inflows to surface water can be made using a simple drum and plastic bag as described by Bokuniewicz and Zeithin (1980). Continuous measurements of groundwater seepage can be made using an ultrasonic groundwater seepage meter (Paulsen, et al., 1997) (O Rourke, et al., 1999). Discharge to the sea Underground discharge to the sea occurs in considerable volumes, which may be estimated from observations of groundwater flow and aquifer thickness. Point measurements may be made using either the drum method or an ultrasonic groundwater seepage meter as mentioned above. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 23

31 AQUIFER CHARACTERISATION FIGURE 4: GRAPHICAL REPRESENTATION OF THE CHARACTERISTICS OF GAINING (LEFT) AND LOSING (RIGHT) STREAMS. THE BOTTOM IMAGES SHOW THE GROUNDWATER FLOW LINES. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 24

32 NUMERICAL GROUNDWATER MODELLING 1.8 NUMERICAL GROUNDWATER MODELLING Background Groundwater models play an increasingly important role in groundwater management. Through the construction of numerical models we are able to simulate the response of aquifers and surface water resources to abstraction, land-use change and the effects of climate changes before such events become a reality. Numerical modelling offers the opportunity to generate a simulation of field conditions. When considering issues of groundwater management and groundwater contamination, models help to develop an understanding of the problem and can be used to find the best solution among several, in terms of both effectiveness and cost-efficiency. Numerical Models Limitations of Hydrogeological modelling A numerical model attempts to simulate groundwater flow indirectly by means of a governing equation thought to represent the physical processes that occur in the system, together with equations that describe heads or flow along the boundaries of the model. For time-dependent problems, an equation describing the initial distribution of heads in the system is also needed (Anderson and Woesner, 1992) It must be strongly emphasised that numerical models are only simple representations of a very complicated reality. Through the use of Graphic User Interfaces the outputs however appear very convincing regardless of the quality of input and skills of the modeller. The results should always be subject to a professional quality control. One of the main difficulties in modelling groundwater flow and mass transport is the heterogeneity of the geology and the flow systems. Measures to overcome such heterogeneities have been developed for the large, intermediate and small scales. When dealing with large scale structures we use in situ surveys and borehole measurements, followed by deterministic modelling; while for small scale structures we use some kind of averaging and representation (Tsang, 2000). Steps to constructing Hydrogeological models The development of hydrogeological models can be complex and time consuming. A thorough understanding of the hydrogeological system is an important requirement for the construction of the model. The conceptual understanding is often based on other processes such as the hydrocensus, exploration drilling, hydraulic testing, and recharge estimation. The complexity of the model to be developed will depend on the scale of the study site and the level of output detail required; while the availability of budget, time, expertise and infrastructure/software will define the model construction options. The steps proposed for the development of a hydrogeological model are stipulated in Anderson and Woessner, 1992, and Tsang, Sustainable Yield estimation The estimation of the sustainable yield of an aquifer depends on an understanding of the long-term average recharge of the aquifer. Numerical modelling offers a method for obtaining dynamic and cumulative recharge estimates (Merrick, 2000). GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 25

33 NUMERICAL GROUNDWATER MODELLING Interaction of surface water and groundwater Assessing the interaction of groundwater and surface water forms an important component of resource accounting, especially in the determination of the groundwater reserve. Numerical models provide a tool for estimating the contributions of groundwater to stream flow, and the sustenance of water levels in surface water bodies such as lakes and wetlands. In groundwater - surface water interaction models, the surface water features are usually treated as fixed heads, and Darcy s law is used to assess the water exchange. Care is advised in using tools that simulate the interaction of groundwater and surface water, as they have been developed with a particular field situation in mind that may not necessarily reflect local conditions. Groundwater Surface water modelling is a specialised field that requires the participation of a modeller experienced in its application. The work of Kelbe and Germishuyse (2000) serves as an illustration of the way in which Groundwater - Surface water models can be applied to address water resource management issues in South African coastal aquifers. A list of Computer Methods for Water Resources Assessment is included as part of level 4 in the guidelines. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 26

34 ENVIRONMENTAL CONSIDERATIONS 1.9 ENVIRONMENTAL CONSIDERATIONS Strategic Environmental Assessment: SEA Strategic Environmental Assessment offers a process that assesses larger scale projects or developments in a holistic manner, by taking account of environmental, social and physical factors in the development of natural resources. The holistic nature of SEAs makes it ideal for WMA level planning of water resources development. It is thus important that the insight and understanding of the groundwater resources of an area be placed within the SEA context. The guiding principles for SEA are listed below. Guideline Principles for SEA in South Africa: SEA is driven by the concept of sustainability. SEA identifies the opportunities and constraints, which the environment places on the development of policies, plans and programs. SEA sets the criteria for levels of environmental quality or limits of acceptable change. SEA is a flexible process which is adaptable to the policy, planning and sectoral development cycle. SEA is a strategic process, which begins with the conceptualisation of the policy, plan or programme. SEA is part of a tiered approach to environmental assessment and management. The scope of a SEA is defined within the wider context of environmental processes. SEA is a participative process. SEA is set within the context of alternative scenarios. SEA is based on the principles of precaution and continuous improvement in achieving sustainability objectives. Source: SEA Guidelines prepared for Department of Environmental Affairs and Tourism by CSIR, 2000 as sighted in DWAF (2001) Analysis of opportunities and constraints Once the total water resources of an area have been reasonably assessed, the use of opportunities and constraints analysis may provide valuable insight into the most appropriate resource for exploitation. Such an analysis is area specific, and follows from a needs determination. Table 2 below summarises the most important criteria to be considered in such an analysis. Each of the criteria listed is evaluated in terms of its sustainability and an evaluation of the costs and benefits that would follow from the development of a particular water resource. It should also be emphasised that conjunctive use often offers an opportunity to maximise the benefits associated with different sources of supply. The table below summarises the costs and benefits that are typically associated with a water resource derived from: Water Conservation/Water Demand Management (WC/WDM), Surface Water, Groundwater and the Desalination of Seawater. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 27

35 ENVIRONMENTAL CONSIDERATIONS TABLE 2: SUMMARY OF TYPICAL OPPORTUNITIES AND CONSTRAINTS FOR DIFFERENT WATER SOURCES Constraint issues are in shaded italics. Economic Social Availability Technology Required Engineering/ Infrastructure Environment WC/WDM (Water Recycling) Maximises use of available resources reducing need for new developments Cost of treatment is high for some uses Educates communities on the value of water Cultural aversion to use of recycled water. Possible in most urban and some irrigation areas Layman education insufficient Education is most important. Technology for retro fitting is available Re-use of waste water requires advanced treatment Can be behavioural rather than engineered Retro fitting limited to industry and higher income groups Reduces resource impacts Treatment may be energy intensive Surface Water Groundwater Desalination of Seawater Associated uses for dams (recreational, fishing, etc.) and flood control Generally expensive; Infrastructure costs increasingly high as easy targets disappear Is often preferred source and dams create recreational environment. Population displacement in relation to larger dams. Limitations to local control and participation. Allow storage and planning Limited distribution; Evaporation losses; Seasonally variable Tried and tested extensively Specialised Long life expectancy Requires extensive construction and often lengthy pipeline Vulnerable to sabotage Increased aquatic habitat with dam construction Potentially huge environmental impact when dam building Often most inexpensive option, with higher assurance of supply Resource assessment costs high Local control/management is possible Hand or wind pump delivery perceived as second rate Distributed widely. Seasonally reliable Difficult to understand for the layman Readily available, with various energy sources (hand/wind/diesel) Some prone to breakdown without proper maintenance Usually only local infrastructure needed Increased uncertainty in development of resource, especially by nonhydrology scientists Generally limited impact on ecosystems May impact on groundwater dependant ecosystems Small scale possible for coastal communities High operational and capital costs Relatively secure Alienating technology Seawater quantity not a limiting factor Brine water Restricted to coastal areas New technology required to improve feasibility Many sites available Big plants are most viable Limited impact on water source Waste by-product and significant energy impact. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 28

36 REFERENCES 1.10 REFERENCES REFERENCES ARE INCLUDED IN LEVEL 4 OF THE GUIDELINES GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 29

37 EXECUTIVE SUMMARY CHAPTER 2 GROUNDWATER RESOURCE ALLOCATION EXECUTIVE SUMMARY Context The National Water Act gives an allocation priority to categories of water use as follows: The Reserve, International Obligations, Schedule 1 Activities, General Authorisations, and Existing Lawful uses. Following these allocations groundwater should be allocated to individual/compulsory applicants whilst ensuring: Improved equity of access to resources Optimal use of groundwater in terms of assurance and distribution of supply Optimal beneficiation Efficient use, and Sustainable use. Role of the groundwater coordinator In order to ensure equitable, sustainable and efficient allocation, the groundwater coordinator needs to understand the socio-economic context and vision for development in the Water Management Area. He/ She needs to be able to communicate to stakeholders and decision makers issues like: The availability of groundwater Characteristics of the resource which increase its value, and Means to sustainable management. Communication to previously disadvantaged groups is particularly important. Tools for communication vary in sophistication and accuracy. Simple diagrams and sketches are useful to impart a conceptual understanding of the catchment in three dimensions. Numerical optimisation software and multi-criteria decision analysis will require a high quality of considered input from the groundwater coordinator. The Groundwater coordinator will need to make a first estimate of annual volumes of groundwater abstracted for Schedule 1 uses, General Authorizations and Existing Lawful Uses. This will be an essential part of the groundwater balance for the WMA. A precautionary, phased approach is recommended for allocating the remaining utilizable groundwater in the catchment, once the requirements of the RQOs and international obligations have been met. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 30

38 EXECUTIVE SUMMARY Recommendations. Predicting the impact of groundwater allocations and determining optimal patterns of use are a key challenge to the groundwater coordinator. Water allocation managers need to understand available volumes, water quality and assurance of supply. The groundwater coordinator needs to understand how aquifer characteristics, which influence these values, vary within the resource, what are the critical thresholds (RQOs) and to what degree of confidence the necessary data are known/quantified. Another key challenge facing the groundwater coordinator is converting the intrinsic heterogeneity and unpredictability of hidden groundwater systems into a reliable resource for supply. This should be achieved by applying the principles for sustainability, equity and efficiency within the management of the groundwater resource. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 31

39 INTRODUCTION 2.1 INTRODUCTION Water resource allocation is one of the core functions of DWAF and will be of the CMAs. Priority uses of water are pre-allocated under the NWA and include the quantity and quality of water required for the Reserve and Resource Quality Objectives (RQOs), International Obligations, Schedule 1 uses, General Authorisations and Existing Lawful uses (see section 5.2 for definitions of these terms) and can be seen in Figure 5. An estimation of the total sustainable yield of the resource and the quantities of groundwater required for these uses should be made to determine how much groundwater remains for sustainable licensed allocation. These estimates will be made through: The resource assessment (Volume 2, Chapter 1); Determination of the Class, Reserve and Resource Quality Objectives (Volume 2, Chapter 3). Hydrocensus and groundwater monitoring (Volume 2, Chapter 4), and The groundwater coordinator needs to be clear about levels of confidence in these estimations. It is accepted that confidence will be low initially but will improve with time and the range of monitoring conditions. In many aquifers, the priority uses of groundwater listed above will place not only volumetric, but also quality and water level constraints on the remaining water available. The position of licensed abstractions, as well as the pumping schedule and depth of abstraction, may need to be included in license conditions to ensure that other priority uses, particularly the RQOs, are not infringed. The water allocation plan is key to the Catchment Management Strategy and will require the considered participation of the groundwater coordinator. The strategy for groundwater allocation should highlight the benefits and value of groundwater in the catchment (drought resilience, protection from pollution, etc) and ensure that the resource is used optimally. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 32

40 INTRODUCTION I N C R E A S I N G I M P A C T Likely impact Common use: Low or normal impact Widespread use: Low or normal impact LICENCE Reserve determination Other use allocations Registration Monitoring and reporting Charges GENERAL AUTHORISATION Applicable to all Some registration Some monitoring Some reporting SCHEDULE ONE Detailed Use not known to Department FIGURE 5: HIERARCHY OF WATER USE AUTHORISATION UNDER THE NATIONAL WATER ACT (SOURCE: BRAUNE, ED. SILILO ET AL, 2000) Key principles relating to the allocation of water resources are: Lawful rights to water use which pre-date the NWA should be protected, subject to public interest, or where they are reduced or removed, should be compensated. All citizens have the right to access to basic water services. Responsibility for the development, apportionment and management of available water resources should be delegated to a catchment level to enable interested parties to participate and reach consensus. The rights to use water should be allocated in good time and in a manner that is clear, secure and predictable in respect of assurance of availability, extent and duration of use. Water resources should be developed, apportioned and managed in such a manner as to enable all user sectors to gain equitable access to the desired quantity, quality and reliability of water. In order to realise these principles the groundwater coordinator will need to integrate with surface water coordinators, integrated water resource managers, water service providers, water user associations and other catchment stakeholders. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 33

41 HOW TO RECONCILE SUSTAINABILITY, EQUITY AND EFFICIENCY 2.2 HOW TO RECONCILE SUSTAINABILITY, EQUITY AND EFFICIENCY WITH GROUNDWATER QUANTITY AND GROUNDWATER QUALITY Sustainability Also see sustainability in Volume 1, Chapter 4. The currently accepted understanding of environmental sustainability was formulated by Brundtland (1987). In terms of groundwater abstraction, sustainable yield can be viewed as the amount of water that can be abstracted to meet the need of the current generation without compromising the ability of future generations to meet their needs. It is reasonable to assume that the needs of future generations will be similar to our own, with increasing magnitude as the size of population and standard of living increases. In the case of most aquifers therefore, sustainability means maintaining the functioning of the aquifer in terms of the quality and quantity of water available to be used. It is usually acceptable to abstract only what can confidently be expected to be recharged in the short to medium term (average annual recharge). Sustainability of the aquifer resource needs to be protected through: Controlling the total volume of water abstracted. Controlling the impact of land-based activities. Placing conditions on the situation under which water may be abstracted. The allocation of water and the conditions under which it is allocated are therefore critical controls in sustainable groundwater use. Water allocation mechanisms need to take into account the mechanisms for water resource protection (Resource Directed Measures, Source Directed Controls Volume 2, Chapter 3). In order to ensure sustainable use of a groundwater resource the system and its sustainable limits need to be understood. This requires long term monitoring data and an understanding of the critical points of no return and irreversible damage. Irreversible damage may be considered as the loss of a critical function of the aquifer for the duration of more than a century (100 years). Common triggers of irreversible damage include: Mining of groundwater abstraction of groundwater at significantly more than recharge rates, particularly fossil groundwater which is receiving little or no modern recharge. Land subsidence as a result of lowering water tables (dolomites, limestones and unconsolidated primary aquifers), which irreversibly reduces the storage capacity of the aquifer. Saline intrusion of the aquifer as a result of lowered water tables near the coast or overlying saline aquifers, and Contamination of groundwater, particularly where a contaminator is stored in the aquifer by diffusion into storage water in a dual porosity aquifer or adsorption to the matrix. Fracture zones that get dewatered cause irreversible damage to this groundwater flow conduits. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 34

42 HOW TO RECONCILE SUSTAINABILITY, EQUITY AND EFFICIENCY The following legal and regulatory tools are available to the groundwater coordinator in the CMA to ensure the sustainable functioning of aquifers in WMA: Setting the Class, the consequent RQOs and the Reserve (Volume 2, Chapter 3) will outline the limits of socially acceptable impact to the functioning of the groundwater system. It is possible that these will exceed environmentally sustainable limits. For example, in a highly water stressed area a decision may be taken to mine groundwater or industrial development in an area may prioritise dewatering over the maintenance of aquifer integrity (subsidence). Non-allocation to unsustainable uses or levels of use. Setting licensing conditions which Limit drawdown of the groundwater level Prescribe the type of pumping technology used (i.e. to low abstraction continuous rate technology) Limit the depth of boreholes, well or pump installation Prescribe monitoring data to be collected Demand abstraction to be managed within certain boundary conditions In addition to using the regulatory instruments at his/her disposal the Groundwater coordinator needs to ensure a greater level of understanding and awareness of the importance of sustainability to assure groundwater supply, and resolve competition between users for short term, unsustainable gains. Sustainable use of a groundwater resource is dependent on: 1. Resource quantity: Typically, the amount of groundwater to be abstracted from any one scheme needs to be less than the recharge to that part of the aquifer. This will ensure that groundwater is available to fulfil its environmental functions in addition to the other uses. This element of sustainability relates most closely to the safe yield concept, derived from water balance estimations (Volume 2, Chapter 1). Where there is low confidence in the water balance estimations, a precautionary estimate of abstraction volumes should be made. In addition to a volumetric estimation of water available, it is critical to take into account the planned location of abstraction points and the local impacts on established RQOs and the Reserve. A WRC project is currently looking at methodologies to set the RQOs in CMAs and is will be available as a report from the WRC. 2. Resource quality: Abstraction as well as land-based activities needs to be managed to minimise the risk of groundwater pollution (see Volume 2, Chapter 3 for more details) or saline intrusion. 3. Appropriate technology: The technology used should be able to meet the demands of the users and be operated and maintained within the constraints of the local environment e.g. has to decide whether hand pumps will be better under certain conditions than an electric pump, or vice versa. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 35

43 HOW TO RECONCILE SUSTAINABILITY, EQUITY AND EFFICIENCY 4. Social acceptance: The local users need to participate in the choice of resource to be developed. If they understand the benefits of groundwater use for their particular circumstances, they are more likely to protect it and use it sustainably. This is a very important factor and should be addressed adequately to avoid vandalism of equipment. 5. Long-term economic viability: Financing of the long term operation and maintenance of the scheme should be understood, as well as the initial capital costs for establishment. 6. Capacity: Capacity needs to be developed at several levels to ensure the long-term support for use of groundwater. The local managers and monitors of the scheme need to be trained (at a municipal or village level). An understanding of the sustainable limits and opportunities for groundwater use should be developed at all relevant levels of decision making within local and provincial government, as well as the CMA and DWAF National Planning Sustainability indicators So how do we know that the resource is managed in a sustainable way or not? Here follows a few indicators that can be used to monitor the status and sustainability of a groundwater resource: Element of sustainability Resource quantity Indicators Water levels. (e.g. fix a maximum draw down for water levels to avoid mining of resource) Isotopic tracers of water age and source. (to determine if system gets recharged frequently to sustain abstraction) Appropriate abstraction schedule that takes into account local hydrogeological conditions and water balance. Implementation of water conservation and demand measures.(eg. not pumping if there are sufficient surface water for users or to reduce pumping if demand gets lower) Resource quality TDS/ EC (indicators of salt loads) Faecal coliforms, NO 3, Fl, contaminants related to local activity. (Elevated levels of these could cause serious health problems) Implementation of protective land management and best wellhead practices. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 36

44 HOW TO RECONCILE SUSTAINABILITY, EQUITY AND EFFICIENCY Appropriate technology Identification of local technology constraints (energy, infrastructure, costs, etc). Identification of hydrogeological operating constraints (depth, corrosive water, recovery periods, acceptably draw down). These can be determined by conducting a pumping test. Selection of pumping equipment and design of borehole and well-head area in recognition of these constraints. Development of the operating plan in recognition of these constraints. Success/ failures of similar schemes. Social acceptance Thorough consultation through Public Participation Process Level of ownership of the scheme by users. Accomplish with adequate capacity building and operator training. Long-term economic viability Development and implementation of business plan with necessary capital cost recovery. Transparency and accountability in the collection of tariffs. Implementation of sufficient accounting procedures. Capacity Understanding of groundwater use constraints and opportunities in local, provincial and national decision makers. Trained scheme operator on the ground. Sufficient mechanisms for communication/ integration of understanding and decision making (water committees, catchment forum meetings, etc) Equity Water is essentially a tool to transform society towards social and environmental justice and poverty eradication. Schreiner and van Koppen, The historical and current distribution of resources in South Africa undoubtedly reflects previous inequitable access to land and water. Over 70% of the poor live in rural areas. 13% of the population owns 87% of the land. Over 80% of groundwater abstracted is used for irrigation and over 95% of this is used by large-scale farmers. Most current groundwater abstraction therefore is used to support historically advantaged commercial enterprise. The allocation of groundwater therefore has a vital role to play in redressing the imbalances of the past and alleviating poverty, particularly rural poverty, through increasing water and food security. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 37

45 HOW TO RECONCILE SUSTAINABILITY, EQUITY AND EFFICIENCY Emerging farmers A large section of the South African population still live in rural areas. This represents the larger part of the 10 to 12 million South African that remain without access to clean drinking water. It is recognised that access to clean water represents an important component to national poverty eradication strategies. The supply of water to the rural poor not only serves for drinking supply, hygiene, and cooking, but also makes possible income generation through crop cultivation and livestock herding. The supply of water often also coincides with the establishment of village-based enterprises such as beer brewing, brick making, dairying and construction (Butterworth, et al., 2001). The availability of land has limited the number of previously disadvantaged South Africans in agricultural practices. Where land is available to emerging farmers it is often marginal with poor water resources to support development. The problem of access to water is exacerbated by the fact that many river systems are already over utilised. This means that in many cases the development of groundwater resources, often from low yielding aquifers, reduced use in other sectors, and the transfer of water from outside the catchment is the only option available to meet the domestic and developmental needs of many rural communities. There have been successful and unsuccessful experiences in using water allocation to uplift previously disadvantaged communities. An example of a successful experience is the Olifants-Doorn Water Management Area of the Western Cape where a groundwater allocation to (advantaged) commercial farmers was granted on condition that some of the water is used to help emerging farmers set up a commercial enterprise. The advantaged farmers were bound to support new farmers in their endeavours. The development proceeded over the course of three years with significant input and facilitation from water managers in the area. Many social, economic and cultural factors influence the success of groundwater allocation to emerging farmers. However, the Groundwater coordinator can play an active positive role in ensuring sufficient understanding of the resource, managing expectations of delivery and return on investment and that water quality, irrigation practices, etc are appropriate for the local environment. The United Kingdom s Department for International Development (DFID) and the South African Department of Water Affairs and Forestry have jointly formulated an extensive Water and Forestry Support Programme. One of the components in this programme is Water Resources Management with the following purpose: To support the establishment of processes and systems for water resources management under the National Water Act that ensure the participation of all stakeholders, with an emphasis on poor and marginalized groups. One of the outputs of the project will be the Development of the Water Allocation Methodology which will be in the form of a toolkit for water allocation planning. The main aim for the toolkit will be to provide capacity to pro-actively secure water for emerging users and would be a useful tool in the CMA. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 38

46 HOW TO RECONCILE SUSTAINABILITY, EQUITY AND EFFICIENCY Drought proofing subsistence livelihoods Groundwater is particularly important when dealing with risk management. Poor people living a hand-to-mouth existence have little resilience for crises and droughts have a devastating impact. Groundwater, with its greater storage potential, is more droughtproofed than surface water. These resources should be available to support basic needs at times of crisis and may require a Reserve or strategic allocation that differs from our current understanding of the NWA. The current definition of the Reserve includes an allocation to meet basic human needs. However, a strategic reserve of groundwater may be required by the poor to sustain their livelihoods in times of drought. Supply of Free Basic Water As part of national government s commitment to the alleviation of poverty, the supply of free basic water to all users has been implemented by DWAF. Within this policy, government has decided to ensure that poor households are given a basic supply of water free of charge. The present policy aims to provide litres of safe water per household per month (Kasrils, 2001). The motivation for the free supply of basic water is based on consideration of the benefits to public health and well-being; equity and welfare; and gender reasons (Kasrils, 2001). The Free Basic Water implementation strategy (DWAF, 2001b) recognises that free basic water cannot be provided to communities where not even a basic supply of water exists. Acceleration in the delivery of water and sanitation services is therefore underway. It is generally accepted that the development of groundwater resources will play an important role in meeting the objectives of poverty alleviation and the supply of free basic water. In large parts of South Africa groundwater is the only viable water source available, while in other areas it offers a relatively inexpensive alternative to the construction of large dams and long distance distribution networks. In summary, the Groundwater coordinator is often in a position to assist emerging farmers and previously disadvantaged communities to develop their local economies by allocating groundwater resources as a priority Efficiency Water use efficiency ensures that water is consumed in a way that minimises wastage and losses. For this to happen it is necessary that water users have a full appreciation of the value of water and a desire to maximise their benefit from the water supplied to them. One of the most obvious ways of ensuring a sense of value is to charge for water use. Other means to improve efficiency are to preferentially allocate water resources to users who demonstrate efficient use and to make efficiency either a prerequisite for allocation of a condition of a license for use. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 39

47 HOW TO RECONCILE SUSTAINABILITY, EQUITY AND EFFICIENCY Charging for water use is structured around many social, economic and resource factors. These include: Ability to pay. Willingness to pay. Willingness to collect payment. Ability to collect payment. Accountability of WSI. Ability to measure use. Implementation of an accepted method of costing. Sliding tariff scales can be used to further increase efficiency. A successful example is the water tariffs introduced in Hermanus (see DWAF website). The costing and valuation of water supply is the role of the resource economist and water service institutions. However, the Groundwater coordinator can contribute to the debate in outlining the goods and services provided by aquifers in the WMA. Groundwater services may be divided into two basic categories (National Research Council, USA 1997): Extractive services (abstraction for domestic, industrial, agricultural uses). In situ services (drought buffering potential, ecological habitat, baseflow to rivers for fish and recreational uses, etc). Each of these categories of services is designated a value to give the Total Economic Value (TEV). The identification of goods and services provided by groundwater is a recommended step in the Classification of aquifers as it helps to define the importance of the aquifer (Xu et al, 2003). Treating environmental systems as economic assets that provide goods and services has become an established approach in environmental economics (National Research Council, 1997). The groundwater coordinator can provide a (usually semiquantitative) conceptual model of the role of an aquifer, and this hydrogeological understanding will be given a quantified value using an accepted valuation method. (See Water as an Economic Good: A solution or a problem. Perry et al, 1997). Trading rights to water use has been used in several countries as a way of improving efficiency of optimal water use (Australia, India, USA). Perry et al (1997) define a necessary and sequential set of preconditions for the beneficial introduction of market forces into the allocation of water. These are: The entitlements of all users under all levels of resource availability are defined and include specified assignments to social and environmental uses. Infrastructure is in place to deliver the defined entitlements. Measurement standards are acceptable to the delivering agency and users Effective recourse is available to those who do not receive their entitlements. Reallocations of water can be measured and delivered, and third-party impacts (in quality, quantity, time, and place) can be identified. Effective recourse is available to third parties affected by changes in use. Users must be legally obligated to pay defined user fees through effective legal and policy procedures. Large-scale transfers of water with and between sectors must be subject to approval and relevant charges by regulatory agencies. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 40

48 HOW TO RECONCILE SUSTAINABILITY, EQUITY AND EFFICIENCY If these preconditions are met, WSIs or even WUAs may opt to trade water rights. This will have implications for the groundwater coordinators management of the resource. Limits to trading will have to be given. For instance, licences should be valid for single uses (ensuring the aims of optimal beneficiation are met) and for a single class of a groundwater management unit or aquifer. Various numerical optimisation software packages are under development to take into account tradable groundwater allocations. These should assist the Groundwater coordinator. Water Demand Management Inefficient water use has been defined by DWAF as: Water used for a specific purpose over and above the acceptable and available best practices and benchmarks or water used for a purpose where very little benefit is derived from it. (Water Conservation and Water Demand Strategy for the Water Services Sector. DWAF. Draft 8 August 2001). Water conservation and water demand management measures (WC/WDM) attempt to ensure efficiency of use and should be implemented for water service institutions (WSIs) and rural and urban end-users alike. A set of guidelines on WC/WDM has been produced as part of this project and gives details on the tools and measures for WC for urban WSIs. More broadly, WC/WDM measures include the Working for Water Programme, leakage detection and repair in bulk reticulation and household retrofitting of water saving devices like dual flush toilets. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 41 VOLUME 2: IMPLEMENATION

49 RECOGNISING THE STRATEGIC BENEFITS AND VALUES OF GROUNDWATER 2.3 RECOGNISING THE STRATEGIC BENEFITS AND VALUES OF GROUNDWATER Groundwater offers several strategic benefits as a source for supply. These need to be taken into account in its development. Even in low yielding aquifers, groundwater is more widely distributed than surface water resources in South Africa. With the aid of appropriate drilling and abstraction technology, groundwater is therefore more widely available directly to users than surface water. As a result of this wide distribution, local scale management of abstraction and use by communities or industry is possible. This means that large-scale infrastructure is not necessarily needed and encourages devolved management and responsibility. It does mean that education and protective controls are critically important to the sustainability of the resource. Centralised command and control measures are less effective for a resource with grass-roots management. Groundwater resources typically represent the majority of stored water in a catchment (up to 95%) and the time that water is stored in an aquifer exceeds surface system storage by orders of magnitude (maybe thousands of years). The greater storage in aquifer systems means that they are buffered from the effects of short-term variations in rainfall and recharge. This means that groundwater can offer greater assurance of supply and is a more reliable source in drought years. Groundwater is better protected from contaminating activities at the surface than surface water, with the unsaturated zone acting as a filter, which removes and/ or decreases the impacts of many contaminants. This is particularly true for microbiological contaminants, which often cannot survive in the unsaturated zone. However, special care needs to be taken at the well-head to prevent contamination of the borehole directly via the casing and handling bailers/ buckets. In summary, groundwater can offer: Better quality. More reliable supply. Wider access. Local control. These characteristics mean that groundwater should be preferentially allocated to uses that require high assurance of supply, wide distribution, protection from pollution and local control. An obvious use is domestic use for basic human needs and small-scale irrigation. In promoting these important uses of groundwater, it is important not to create the image that groundwater is only capable of supplying low yielding, local schemes. Significant groundwater resources are available in South Africa and these can be sustainably developed for cost-effective bulk water supply (e.g. the dolomites and the Table Mountain Group Western Cape). GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 42

50 HOW TO PROVIDE THE TECHNICAL & SCIENTIFIC INFORMATION FOR STAKEHOLDERS 2.4 HOW TO PROVIDE THE TECHNICAL AND SCIENTIFIC INFORMATION FOR STAKEHOLDERS TO ESTABLISH A FAIR AND EQUAL ALLOCATION PROCESS The World Water Vision identified the inability of many stakeholders to conceptualise groundwater as an urgent challenge. This challenge will call on the communication skills of the Groundwater coordinator to transfer their understanding of groundwater conditions in the catchment to a diverse range of stakeholders and decision makers. At the most fundamental level the Groundwater coordinator needs to help stakeholders (and other water scientists) to conceptualise the catchment in three dimensions to take into account the often-significant storage and flow regimes in aquifers. Diagrams and sketches are helpful here and there are several good sources on the internet (e.g. USGS). A variety of tools are available to help the Groundwater coordinator communicate groundwater occurrence and characteristics to stakeholders. Physical models (sand tanks) and cartoons or schematic diagrams are useful to present a conceptual understanding, whilst quantified numerical model outputs may be necessary to inform technical decision makers. The most accurate tools available to determine the impacts of groundwater allocation are numerical models such as Modflow. More information on numerical models is given in Volume 2, Chapter 1. Multi Criteria Decision Analysis Decisions for IWRM (as with all decisions) are based on both implicit (hidden) and explicit knowledge. Tools are needed to help: Make implicit knowledge explicit. Structure practical or decision-making knowledge. People make decisions. There are paper-based tools (e.g. guidelines manuals, maps, flow charts and decision tables) as well as software tools based on algorithms, logic and mathematical equations (e.g. Expert Choice, I Think, Modflow). Software tools can be prepared from expert system shells (e.g. Level 5 Object, Acquire), programming languages (e.g. Visual Basic), database tools (e.g. MS Access) and Spreadsheets (e.g. Excel). For in-house development and use, spreadsheets and MS Access can be very useful, especially for aiding in multi-criteria decision-making. A decision-aid is a tool that: Supplies information to help a decision-maker come to a reasoned decision. Gives advice based on available information and directs the decision maker to other sources of information and advice. (Warning: A decision-aid is designed to aid the decision-maker, not make decisions on behalf of the decision-maker.) GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 43

51 HOW TO PROVIDE THE TECHNICAL & SCIENTIFIC INFORMATION FOR STAKEHOLDERS A multi-criteria decision aid is a tool that does (or helps participants do) a relative comparison of options or alternatives, using a numerical assessment of the criteria applicable to each option or alternative. Options and alternatives (or scenarios) may relate to courses of action, policies, projects, sites, technologies and others. Options are usually ranked and may be presented with known pros and cons applicable to each option. Alternatives are often presented with a descriptive or qualitative evaluation, and may be presented with known pros and cons of each alternative. Typical groundwater problems addressed using this tool include: The assessment of alternative sites for a landfill or sewage treatment works in an area spanning one or more catchments. Assessment of alternative options for sewage sludge treatment/disposal at a specific site. More generally, environmental impact assessments and associated specialist studies. Assessment of the suitability of use of various water (re)sources in a catchment area, considering more than one type of user. In summary The following steps in understanding groundwater resources are typically needed to help stakeholders make better-informed decisions about the management of their resource and have an appreciation of the role it plays in the catchment: 3D conceptual understanding of groundwater in the catchment through cartoons and schematic cross-sections, including recharge and discharge areas. A volumetric estimate of the catchment or aquifer water balance, including an approximation of current abstraction volumes. Groundwater quality and vulnerability maps and cross-sections. A narrative and semi-quantitative comparison of different aquifers and surface water resources with respect to: sustainable yield; quality; distribution; assurance of supply; uses by man and the environment; social and economic value. Possible negative and positive impacts of new allocations. The potential of new groundwater uses within the context of the vision for development within the Water Management Area. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 44

52 HOW GROUNDWATER CAN BECOME PART OF THE MAINSTREAM WATER SERVICE 2.5 HOW GROUNDWATER CAN BECOME PART OF THE MAINSTREAM WATER SERVICE / WATER SUPPLY ACTIVITIES AND DEVELOPMENT The allocation of water resources within a WMA will/should result from the development of an allocation plan for the catchment. This plan will use the values derived during the situational assessment of available water resources and current and future demands for water resources. The processes of situational assessment and allocation planning should fully integrate groundwater and provide records of decision making for preferred sources for development Available groundwater resources. A preliminary estimate of sustainable groundwater resources in the catchment will typically have a lower confidence than for surface water due to the inherent heterogeneity of aquifers (particularly fractured aquifers) and the need to invest more in a reliable delineation of aquifer properties. Groundwater has been cited as our hidden treasure, but its hidden nature means that more needs to be invested in finding it! Volume 2, Chapter 1 of this document provides guidance on assessing available groundwater resources for the different aquifer types found in South Africa. It is always important to record the confidence level of yield assessments. There is a wide range in annual recharge for South African aquifers, from > 200mm p.a. in the wetter eastern parts of the country to less than 5mm p.a. in the dry areas (Braune, 2000) Allocatable Groundwater Resources The amount available for licensed allocation can only be determined once the following has been carried out for groundwater: Available Water Water required for RQOs (incl. Reserve) Water required for International Obligations Water required for Schedule 1 uses, General Authorisations and existing lawful use Water for licensed allocations However, for groundwater more than a simple catchment or aquifer based water balance is required. The location of groundwater necessary for priority uses is critical therefore a GIS based approach is recommended. The groundwater model MODOFC takes into account environmental and priority allocation requirements and recommends optimal abstractions regimes at abstraction points with minimum impact on these prerequisites (Ahlfeld and Riefler, 1999). Allocation to the RDM and International Obligations Once the total available groundwater has been determined from the average annual recharge figures, the amount of groundwater required to meet the requirements of the Reserve, the Resource Quality Objectives (RQOs) and International Obligations needs to be determined. The level of confidence in the determination will vary depending on the estimated current stress placed on the resource. Therefore in highly stressed catchments a comprehensive groundwater Resource Directed Measures (RDM) assessment should be carried out (DWAF, 1999a). GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 45

53 HOW GROUNDWATER CAN BECOME PART OF THE MAINSTREAM WATER SERVICE This is expected to require substantial investment. Volume 2, Chapter 3 of this document deals in more detail with the RDM process, which includes classification, the Reserve and RQOs (Xu et al, 2003; DWAF, 1999a). Guidance on determining International Obligations for groundwater has not yet been given in detail. Essentially, local hydrogeological knowledge would be relied upon to indicate where groundwater outflow/inflow across international borders occurs. This may include baseflow to rivers, which form borders (Orange River), alluvial aquifers at ephemeral river borders (Limpopo), surficial (Kalahari) and deep (Karoo) trans-boundary aquifers. The issue of transboundary aquifer management is currently being addressed by the SADC Water Sector Coordination Unit and the International Association of Hydrogeologists. Allocation to Schedule 1 uses. Following from an estimation of the above priority uses for groundwater, an estimate should be made of the Schedule 1 consumption of groundwater. Schedule 1 is appended to the NWA and describes activities which are expected to have minimal impacts. They include uses such as: a) water for reasonable domestic use in that person's household, taken directly from any water resource to which that person has lawful access; b) water for use on land owned or occupied by that person, for - (i) (ii) (iii) reasonable domestic use; small gardening not for commercial purposes; and the watering of animals (excluding feedlots) which graze on that land within the grazing capacity of that land; c) store and use run-off water from a roof; d) in emergency situations, take water from any water resource for human consumption or firefighting; e) for recreational purposes to which that person has lawful access; or f) discharge - (i) waste or water containing waste; (ii) or run-off water, including stormwater from any residential, recreational, commercial or industrial site, into a canal, sea outfall or other conduit controlled by another person authorised to undertake the purification, treatment or disposal of waste or water containing waste. An entitlement under this Schedule does not override any other law, ordinance, bylaw or regulation, and is subject to any limitation or prohibition. A hydrocensus would give reasonably accurate estimates of uses in this Schedule. If the resources are not available to carry this out, estimates from socio-economic data would probably give sufficient accuracy. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 46

54 HOW GROUNDWATER CAN BECOME PART OF THE MAINSTREAM WATER SERVICE Allocation to General Authorisations and Existing Lawful Uses General Authorisations have been issued in order to set a cut-off point below which strict regulatory control is not necessary (DWAF, 2000a). The General Authorisations have been set for different catchments and aquifers in South Africa. Exclusions to the General Authorisations relevant to groundwater include: Irrigation with wastewater may only take place > 100 metres from a borehole which is used for drinking or stock watering. Irrigation with wastewater may not take place on land, which overlies a major aquifer. Artificial recharge of groundwater may only take place with a licence. These may be open to later debate, particularly wastewater irrigation on land overlying aquifers, as the exclusion follows the precautionary approach and takes no account of aquifer vulnerability. The Groundwater coordinator should conduct a water balance of the WMA to account for the maximum limit of groundwater abstraction under General Authorisations and registered existing lawful uses. Wentzel and Smart (2002), have drafted a revision of the groundwater component of the General Authorisations, and these revisions are soon to be gazetted. The revision proposes an increase in the number of zones from four to six, to ensure the General Authorisations will not exceed 80% of the Harvest Potential. It is also proposed that the General Authorisations be based on 50% of the difference between the Harvest Potential, Existing Use and a portion of the groundwater contribution to baseflow. It is assumed that the basic human needs Reserve requirements are catered for in the Existing Use and the removal of a portion of the baseflow before allocation would ensure that the ecological Reserve is protected. This approach is significant in areas where groundwater is already heavily utilised. As in the current General Authorisations, it is proposed that the old Groundwater Control Areas be excluded from the General Authorisations. In order to be more consistent, all quaternary catchments that intersected control areas were by default downgraded to be excluded and the control areas are not listed separately as in the existing General Authorisations. In the revised General Authorisations report (Wentzel and Smart, 2002), a complete listing is provided of the groundwater abstractions permitted per quaternary catchment. Existing lawful uses of groundwater are also included in the non-licensed water budget of a catchment. Section 32 of the National Water Act of 1998 (Act 36 of 1998) identifies water uses that were authorised under legislation, which was in force immediately before the date of commencement of the National Water Act of 1998 (Act 36 of 1998) as existing lawful water uses. Data on abstraction volumes and their locations have been captured in the registration process and are now in the WARMS database. More information on this database is given in Volume 2, Chapter 5. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 47

55 HOW GROUNDWATER CAN BECOME PART OF THE MAINSTREAM WATER SERVICE Licensed Allocations The final tier of groundwater allocation is licensed allocations. These may be either an individual application, possible in unstressed areas with an assessment by the applicant of likely impacts, or a compulsory application in a WMA that has been identified as water stressed. In water stressed areas even General Authorisations and Existing Lawful Uses need a compulsory license. It is not clear at this stage whether compulsory licenses will be necessary for all water resources in a stressed area or only the resource that is known to be stressed. In areas with low levels of continuity between groundwater and surface water it is possible that one source may experience stress in isolation. The water allocation plan of the CMS indicates the conditions and aims of licensed water use. These should be set in the context of sustainable development of the WMA and the strategic environmental opportunities and constraints inherent to the region. The development of water resources needs to be part of a larger integrated resource planning process and this may happen within a Strategic Environmental Assessment (SEA) framework. A definition adopted for Integrated Resource Planning is: A way of analysing the change in demand and operation of water institutions that evaluates a variety of supply and demand factors to determine the optimal way of providing water services. A path is chosen that will ensure reliable services for the customers. This path must include: economic efficiency and stability, a reasonable return on investment for the institution, environmental protection and equity among ratepayers. The groundwater coordinator will need more than a simple water balance understanding of hydrological processes in the WMA in order to determine what and where groundwater resources are available for licensed allocations. The Classification process advises the development of an integrated conceptual model of surface and groundwater resources within the WMA and a full inventory of groundwater uses. These uses should include inherent environmental uses such as groundwater fed baseflow and supporting vegetation during dry periods. An inventory of uses should be followed by a valuation of those uses, or goods and services provided, by the catchment stakeholders. Important uses/services will require a higher level of protection. This is afforded by the RQOs, which should be articulated to protect key attributes of the aquifer (e.g. water levels for basic human needs from shallow wells). The RQOs along with other monitoring requirements will then form the basis for license conditions. A format for recording decisions made as part of the authorisation process, including a checklist of issues, is given in the process guidelines (DWAF, 2000a). The process to submit and receive an application for licensed use in unstressed catchments (individual authorisation) consists of the following stages: GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 48

56 HOW GROUNDWATER CAN BECOME PART OF THE MAINSTREAM WATER SERVICE Stage 1 Legal validation of the need for a license. Stage 2 Pre-assessment to determine the need for water use. Stage 3 Stage 4 Determine the scope for investigations necessary to reach a decision on the license application. Conduct investigations, including Reserve determination. Stage 5 Submit a summarised integrated application including a report of the investigations. Stage 6 Final decision on granting the license. The division of roles and responsibilities between applicants, CMAs and DWAF is currently being documented (Haupt, in prep.). This should give valuable guidance to groundwater coordinators within the WMAs. A seven-step procedure for licence processing has been developed by DWAF and a summary table, including tools recommended for each step, is given (DWAF 2000a). The information needed to determine a water balance for groundwater within a catchment is often insufficient for a high (or even moderate) degree of confidence in the amount of water available to be allocated. For this reason it is advisable to follow a precautionary and phased approach to allocation. This will minimise the risk of unacceptable impacts occurring as a result of groundwater abstraction and minimise the financial risk of investing in infrastructure for use beyond the limits of confident assessment. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 49

57 REFERENCES 2.6 REFERENCES Ahlfeld, D. P. and Riefler, R G. Documentation for MODOFC: a program for Solving Optimal Flow Control Problems based on MODFLOW Simulation. Version 2.11, pp November 15, Braune in Groundwater: Past Achievements and Future Challenges. Proceedings of the XXX IAH Congress on Groundwater: Past Achievements and Future Challenges, Cape Town, South Africa, 27/11-1/ Edited by Oliver Sililo et al, The Water Programme, Environmentek CSIR, South Africa, pp Brundtland, G. M., Our common future. World Commission on Environment Report. Oxford University Press. Butterworth, J., Mogkope, K., and Pollard, S., 2001, Water resources and water supply for rural communities in the Sand River Catchment, South Africa, 2ndWARFSA/WaterNet Symposium: Integrated Water Resources Management: Theory, Practice, Cases: Cape Town October 2001, University of the Western Cape, pp Department of Water Affairs and Forestry, 2001b, Free Basic Water - Implementation Strategy Version 1, May 2001, Pretoria. DWAF, 2000a. Water Use Authorisation Process for Individual Applications. Edition 1: Final draft fro implementation and use. National Water Act, Act 36 of DWAF, 1999a. Water Resources Protection Policy Implementation Resource Directed Measures for Protection of Water Resources Integrated Manual. Report No. N/28/99, pp Senior Author: H M MacKay. Haupt, C.J., in preparation. The Role Of Geohydrology In The Water Use Authorisation Process Licensing. Kasrils, R., 2001: Minister of Water Affairs and Forestry, Debate on the President s State of the Nation Address, 14 February 2001, Parliament, Cape Town. National Research Council Valuing Ground Water. National Academy Press. Perry, C.J., Rock, M., Seckler, D. Water as an Economic Good: A Solution or a Problem? Research Report 14. International Irrigation Management Institute, Shah, T Integrating water markets in sustainable water resource management. Anand, India: Policy School. 41p. Schreiner, B and Van Koppen, B. Catchment Management Agencies for poverty eradication in South Africa. Reprinted from 2nd WARFSA/WaterNet Symposium: Integrated Water Resources Management: Theory, Practice, Cases; Cape Town, October 2001, pp GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 50

58 REFERENCES Wentzel, J. and Smart, M., Revision of the General Authorisations No 1191 as set out Government Gazette No 20526, 8 October 1999 Groundwater Component. DWAF, Pretoria. Xu, Y., Colvin, C., van Tonder, G., Hughes, S., le Maitre D., Zhang J., Mafanya T., Braune E., Towards the Resource Directed Measures: Groundwater Component (Version 1.1). Final report prepared for the Water Research Commission on Projects K5/1090, 1091 & WRC Report No /1/03. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 51

59 EXECUTIVE SUMMARY CHAPTER 3 GROUNDWATER MANAGEMENT AND PROTECTION APPROACHES EXECUTIVE SUMMARY Context This chapter outlines existing strategies for groundwater quantity and quality management in South Africa. These strategies exist at varying levels of detail, but should all be realised with the implementation of IWRM at a catchment level. Groundwater quality protection strategies are outlined in the document Policy and strategy for groundwater quality management in South Africa (DWAF, 2000). The National Water Act gave rise to: Resource Directed Measures (Classification, the Reserve, Resource Quality Objectives) Source Directed Controls Remediation Strategies. The three core strategies of water quality management are supported by cross-cutting strategies of public participation and capacity building. The CMA must play a role in educating communities to protect their own groundwater resources by the implementation of initiatives such as wellhead protection programmes. This chapter gives guidance on existing best practices and step by step methodologies which may be used to realise the goals of protection strategies and an extensive list of sources of additional information. The role of the groundwater coordinator In order to realise the effective protection of groundwater resources, the groundwater coordinator within a CMA will need to have a broad understanding of: Aquifer importance Aquifer vulnerability The role of groundwater in the broader environment Potentially polluting activities. Aquifer protection A differentiated approach will be needed to make best use of available resources and ensure that least risk is posed to the most important aquifers. The groundwater coordinator will need to understand where groundwater resources are most vulnerable in the catchment, and liase with land-use planners to ensure that contamination threats are minimised. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 52

60 EXECUTIVE SUMMARY Risk assessment and impact assessment provide important tools for prioritising actions where human and financial resources are limited. The effectiveness of these measures in protecting groundwater resources must be measured by appropriate monitoring and assessment, which is used to refine protection programmes. Effective communication with groundwater users, industry, farmers and other catchment managers will be the key to protecting aquifers. Punitive measures alone will not bring about the desired levels of protection. It will be necessary that a range of important stakeholders in the catchment have an appreciation of groundwater value and vulnerability. Key recommendations. In addition to the roles prescribed by the Act and DWAF guidelines, it is envisaged that the following critical areas will need to be addressed in order to achieve groundwater protection. The provision of educational material for learners, stakeholders and other catchment managers. It is often difficult for non-geohydrologists to visualise groundwater therefore it is particularly necessary to ensure that educational material is available to facilitate discussions on the importance and vulnerability of aquifers. Established links to integrated development and land-use planning at national, catchment and local levels. This is particularly important for groundwater resources as aquifer impacts typically cumulate over extensive recharge areas. The NWA makes provision for land-use controls, but specific guidance has yet to be defined. This may be pioneered in the first CMAs as learning by doing! GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 53

61 INTRODUCTION 3.1 INTRODUCTION Historically emphasis was placed on the protection of the quality of South Africa s surface and marine water resources, while policies and strategies to deal with groundwater pollution were scarce. Under the National Water Act, the status of groundwater has now been changed from private water to public water and new efforts are being made to afford groundwater the same protection enjoyed by surface water resources. Policies and strategies for groundwater quality management in South Africa are now being developed by DWAF with the stated mission: To manage groundwater quality in an integrated and sustainable manner within the context of the National Water Resource Strategy 1 and thereby to provide an adequate level of protection to groundwater resources and secure the supply of water of acceptable quality. The protection of water quality in South Africa is to be achieved by the combination of three core strategies: Resource-directed strategies (chapter 3 of NWA) Source-directed strategies (mainly chapter 4 of NWA) Remediation strategies (chapter 3 of NWA) The relationship between these strategies is illustrated in Figure 6. Resource-directed strategies are aimed at understanding the inherent characteristics and current and potential future use of the water resource itself. These are then used to determine the required level of protection. The measures implemented under this strategy are directed at managing such impacts as do inevitably occur in such a manner as to protect the reserve and ensure suitability for the beneficial uses of the resource. Examples of resource-directed measures include: Resource classification. Determination of resource management classes. Reserve determination. Setting of resource quality objectives. 1 Section 5 of NWA (1998) requires the progressive development, by the Minister of Water Affairs and Forestry, after consultation, of a National Water Resource Strategy for South Africa. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 54

62 INTRODUCTION Source-directed strategies are aimed at minimising, or preventing at source wherever possible, the impact of developments or activities on groundwater quality. Source directed controls have, in the past, been principally targeted at point sources of pollution to surface waters and coastal marine waters. Examples of sourcedirected controls include: Licences and general authorisations. Standards to regulate the quality of waste discharges. Minimum requirements for on-site management practices. Requirements for minimising water use impacts. Requirements for remediation of polluted water resources. Remediation strategies are aimed at remediating historical groundwater pollution, where practicable, to protect the reserve and ensure at least fitness for the purpose served by the remediation. Under Chapter 4 of NWA, the clean up of contaminated groundwater is the responsibility of the polluter, who must also bear the costs of remediation. In the case where the responsible person(s) cannot be identified or has failed to comply with the law, remedial action may be undertaken directly by the CMA. Remedial measures for which the CMA is accountable include: Setting and evaluating priorities for remedial action Clean-up of abandoned sites Emergency action plans or procedures for accidental spills Groundwater Quality Management Strategy Source-directed Strategies Resource-directed Strategies Remediation Strategies Sectoral Mining sector Industrial sector Waste Sewage treatment Mining waste Agriculture Surface Water Discharge permitting National monitoring Water quality guidelines Groundwater Abstraction control Impact permitting Aquifer management Impact management (diffuse sources) Resource specific Abandoned mines Mine closure Mine liquidation Aquifer cleanups Abandoned disposal sites Disposal site closure Integrated Strategies Monitoring Research Water quality studies Catchment management Auditing FIGURE 6: INTEGRATED STRATEGIES TO MANAGE GROUNDWATER QUALITY IN SOUTH AFRICA (FROM DWAF, POLICIES AND STRATEGIES FOR GROUNDWATER QUALITY MANAGEMENT). GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 55

63 INTRODUCTION Recognising that groundwater management will have limited resources; actions taken by the groundwater coordinator to implement groundwater protection need to be prioritised according to: The value of the groundwater resource The vulnerability of the resource and The risk of adverse impacts on human health and ecosystems The implementation of the three core strategies requires the proactive participation of DWAF and CMAs in cross-cutting strategies for: Land use planning and control, including the regulation, prohibition or control of Land-based activities o activities which might affect groundwater quality and quantity Mitigation measures o which lessen the effects of polluting activities Cumulative impacts Research and education, including establishing an understanding of the: Importance and vulnerability of groundwater resources. Relationship between pollution sources and effects in the groundwater o i.e. the origin of pollutants, the pathways which they follow and their ultimate fate in the environment. These activities of influencing land use and capacity building are reflected in the functions of the CMAs as stipulated in the NWA (Section 80). The initial functions of a CMA are: a) to investigate and advise interested persons on the protection, use, development, conservation, management and control of the water resources in its water management area b) to develop a catchment management strategy c) to coordinate the related activities of water users and of the water management institutions within its water management area d) to promote the coordination of its implementation with the implementation of any applicable development plan established in terms of the Water Services Act and e) to promote community participation in the protection, use, development, conservation, management and control of the water resources in its water management area. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 56

64 INTRODUCTION In addition to these general functions, specific responsibilities of the CMAs in implementing groundwater quality management strategies are advocated in DWAF s Policy and Strategy for Groundwater Quality Management document. These include, among others: Resource monitoring and dissemination of groundwater data Preparation of groundwater resource status reports Development and maintenance of memoranda of understanding with other authorities responsible for land-use allocation and source controls Evaluation of applications and issuing of licences Implementation of remedial action for sites where the responsible person cannot be identified or has failed to take the necessary action Co-operation with the authorities responsible for source-based control to impede the introduction of contaminants into aquifers Control of groundwater abstraction to provide for sustainable utilisation and to prevent or minimise the migration or intrusion of poor quality groundwater Defining source areas and implementing the national wellhead protection programme Public education and assistance and dissemination of public information. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 57

65 PRINCIPLES OF WATER RESOURCES MANAGEMENT IN SOUTH AFRICA 3.2 PRINCIPLES OF WATER RESOURCES MANAGEMENT IN SOUTH AFRICA Water resources in South Africa are managed according to the principles that underpin the National Water Act 2. The principles outlined below are the fundamental tenets of water management in this country. The legislation aims to ensure the enactment and implementation of these principles Principles Underlying Water Resources Management Integrated management Managing uncertainty National asset Sustainability In a relatively arid country such as South Africa, it is necessary to recognise the unity of the water cycle and the interdependence of its elements, where evaporation, clouds and rainfall are linked to underground water, rivers, lakes, wetlands, estuaries and the sea. Water quality and quantity are interdependent and should be managed in an integrated manner, which is consistent with broader environmental management approaches. Water resource development and supply activities should be managed in a manner, which is consistent with broader environmental management approaches. While the provision of water services is an activity distinct from the development and management of water resources, water services should be provided in a manner consistent with the goals of water resource management. The variable, uneven and unpredictable distribution of water in the water cycle should be acknowledged. All water, wherever it occurs in the water cycle, is a resource common to all, the use of which should be subject to national control. All water should have a consistent status in law, irrespective of where it occurs. There shall be no ownership of water but only a right to use it. The national government is the custodian of the nation s water resources, as an indivisible national asset, and has ultimate responsibility for, and authority over, water resource management, the equitable allocation and usage of water, the transfer of water between catchments and international water matters. The objective of managing the quantity, quality and reliability of the nation s water resources is to achieve optimum long-term social and economic benefit for society from their use, recognising that water allocations may have to change over time. The development and management of water resources should be carried out in a manner, which limits to an acceptable level the danger to life and property due to natural or man-made disasters. 2 DWAF, Discussion Document. Water Law Principles. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 58

66 PRINCIPLES OF WATER RESOURCES MANAGEMENT IN SOUTH AFRICA The Reserve Neighbourliness Equity Polluter pays Transparency and accountability The water required to meet peoples basic domestic needs should be reserved. The quantity, quality and reliability of water required to maintain the ecological functions on which humans depend should be reserved so that the human use of water does not individually or cumulatively compromise the long-term sustainability of aquatic and associated ecosystems. The water required to meet peoples basic domestic needs and the needs of the environment should be identified as the Reserve and should enjoy priority of use. International water resources, specifically shared river systems, should be managed in a manner that will optimise the benefits for all parties in a spirit of mutual cooperation. Those allocations agreed to for downstream countries should be respected. In as far as it is physically possible, water resources should be developed, apportioned and managed in such a manner as to enable all user sectors to gain equitable access to the desired quantity, quality and reliability of water, using conservation and other measures to manage demand where this is required. The right of all citizens to have access to basic water services (the provision of potable water supply and the removal and disposal of human excreta and waste water) necessary to afford them a healthy environment on an equitable and economically and environmentally sustainable basis should be supported. The location of the water resource in relation to land should not in itself confer preferential rights to usage. Water quality management options should include the use of economic incentives and penalties to reduce pollution, and the possible irretrievable environmental degradation as a result of pollution, should be prevented. Since many land-uses have a significant impact upon the water cycle, the regulation of land-use should, where appropriate, be used as an instrument to manage water resources. Rights to the use of water should be allocated in good time and in a manner, which is clear, secure and predictable in respect of the assurance of availability, extent and duration of use. The purpose for which the water may be used should not be arbitrarily restricted. The conditions subject to which water rights are allocated should take into consideration the investment made by the user in developing infrastructure to be enable the use of the water. Where water services are provided in a monopoly situation, the interests of the individual consumer and the wider public must be protected and the broad goals of public policy promoted. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 59

67 PRINCIPLES OF WATER RESOURCES MANAGEMENT IN SOUTH AFRICA Catchment level & Public participation User pays In summary. The institutional framework for water management should, as far as possible, be simple, pragmatic and understandable. It should be self-driven, minimise the necessity for state intervention, and should provide for a right of appeal to or review by an independent tribunal in respect of any disputed decision made under the water law. Responsibility for the development, apportionment and management of available water resources should, where possible, be delegated to a catchment or regional level in such a manner as to enable interested parties to participate and reach consensus. Beneficiaries of the water management system should contribute to the cost of its establishment and maintenance. Lawful existing water rights should be protected, subject to the public interest requirement to provide for the Reserve. Where existing rights are reduced or taken away, compensation should be paid wherever such compensation is necessary to strike an equitable balance between the interests of the affected person and the public. An existing right should not include a right, which remains unquantified and unexercised at the time of the first publication of these principles. The development, apportionment and management of water resources should be carried out using the criteria of public interest, sustainability, equity and efficiency of use in a manner, which reflects the value of water to society while ensuring that basic domestic needs, the requirements of the environment and international obligations are met. In addition to the principles identified by DWAF during the development of the new legislation, other important principles are currently being adopted in resources management in South Africa. These are outlined below and should be used to effect integrated catchment management Resource Management principles Cooperative governance Strategic adaptive management (SAM) Strategic Environmental Assessment (SEA) Cooperative governance is a constitutional imperative. The Constitution requires that all spheres of government and all organs of state must observe the principles of cooperative government. (s41(1) of the Constitution). This recognises that effective and efficient governance in a capacity and resource scarce country such as this can only be achieved through a high level of cooperation between government departments. This approach aims to achieve management goals in a flexible way without detailed prescriptive planning i.e. learn by doing. It promotes the practice of form follows function, to avoid inflexible institutional structuring, and relies on consensus building between scientists, managers and stakeholders (Rogers, et al., 2000). This approach applies the principle of understanding the environment and identifying inherent opportunities and constraints. These should influence the choice of development options to improve sustainability. SEAs represent an important decision support tool in that it involves stakeholder participation and provides appropriate information for planning and decision-making, and should be a part of the situation assessment. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 60

68 PRINCIPLES OF WATER RESOURCES MANAGEMENT IN SOUTH AFRICA Risk-based prioritisation Appropriate technologies Goal oriented management Multi-tier tariffs CMAs will not be in a position to address all the water resource issues in their areas. A way to prioritise the issues for attention is to assess the risk of adverse consequences. Risk assessment considers the probability of an adverse event happening (for e.g. an infant consuming water with 50 mg/l nitrate-nitrogen) and the consequences of the event. Situations that present a high risk (high probability of occurrence and/or severe consequences) should be prioritised for attention. South Africa has a high degree of diversity and therefore very varied needs for appropriate technology. Technologies should be sourced and developed to improve efficiency and sustainability of supply. They should be selected taking into account cultural preferences, cost and sustainability. An effective way to achieve consensus between all stakeholders on the goals of water resource management is through developing future scenarios a vision of the catchment in 5 or 10 years time. The scenarios need to be unpacked into a set of resource and supply goals (Resource quality objective, levels of efficiency, supply volumes and quality). Once the goals have been established, current and future obstacles are identified as intermediate objectives. These objectives (or constraints) should be met (or overcome) in order to achieve the goals. This is also known as Theory of Constraints (ToC). This has been successfully applied a pioneering community in South Africa was Hermanus in the Western Cape and can be used to improve efficiency of use. (See the document on Water Conservation/Water Demand management produced as part of this DWAF/DANIDA project.) GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 61

69 IMPLEMENTATION OF RESOURCE DIRECTED MEASURES 3.3 IMPLEMENTATION OF RESOURCE DIRECTED MEASURES GOAL CATCHMENT MANAGEMENT AGENCIES SHOULD SEEK TO DEVELOP A GOOD UNDERSTANDING OF GROUNDWATER QUALITY STATUS, THREATS TO GROUNDWATER QUALITY AND THE RELATIONSHIP BETWEEN THE CAUSES OF GROUNDWATER DAMAGE AND THE EFFECT ON THE RESOURCE. The following resource-directed measures are specified in the NWA (Section 13): A national classification system for water resources including groundwater. Determination of a management class for each resource. Determination of the Reserve which includes the basic human needs reserve (water for drinking, food preparation and personal hygiene) and the ecological reserve, which must be determined for all parts of any significant water resource such as rivers, streams, wetlands, lakes, estuaries as well as groundwater. Setting resource quality objectives, which represent the desired level of protection of a water resource. A method for implementing these resource directed measures has been developed specifically for groundwater by Braune et al (2000). The method involves seven steps, based on the integrated methodology developed by DWAF in 1999, which are summarised on the following pages. Toolbox Reserve has a program to enable the Desktop Reserve Determination or refer to Parsons, RP (2004) Groundwater Resource Directed Measures Training Manual. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 62

70 IMPLEMENTATION OF RESOURCE DIRECTED MEASURES STEP 1: START THE DETERMINATION OF RESOURCE DIRECTED MEASURES Who What How Outputs Hydrologist, hydrogeologist, groundwater coordinator, ecologist. Initiate the RDM study 1. Delineate geographical boundaries i.e. where? 2. Select level of detail of RDM study & components i.e. what? Desktop: Basic human needs and ecology unimportant Rapid: for small impacts in low sensitivity, unstressed catchment where a low confidence level is sufficient. Intermediate: for unstressed catchment. Comprehensive: for large impacts, or important resources or stressed catchments where higher confidence is needed. 3. Establish study team i.e. whom? 1. Expert knowledge of the area and potential impacts. 2. Expert local scientific and management understanding of the catchment: Study approval D conceptual model of the area, boundaries 2. Study levels defined. 3. Team appointed. STEP 2: DELINEATE THE RESOURCE UNITS (Geohydrological Regions) Who Hydrogeologist, groundwater coordinator, ecologist What How 1. Determine groundwater regions. 2. Determine groundwater response units, based on hydrogeological characteristics. 3. Determine groundwater management units, based on use of groundwater. 4. Select sites for RDM study (relatively homogenous units for which the reserve can be determined and protection criteria established) 1. Expert consideration and GIS overlay of climatic zones, geology, ecoregions, geomorphology. Vegter s geohydrological regions. 1: hydrogeological maps. 2. Local expert consideration and analysis of drilling and pump testing data (reports, Open-NGDB), borehole prospects map, hydrogeochemical data (TDS/ EC), hydrogeological maps and detailed geological maps. Items in italics are only required for a comprehensive RDM study. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 63

71 IMPLEMENTATION OF RESOURCE DIRECTED MEASURES 3. Expert assessment of direct and indirect uses of groundwater by man and the environment in the catchment from maps, known land-uses and licences. Hydrocensus of important areas of use. Environmental auditing of major impacting activities. Ecohydrological investigations of groundwater dependent ecosystems. 4. Scientific and management expertise to select sites which are typical (representative) of the response units and uses of groundwater in the area. Also those sites which will aid understanding of boundary conditions. Outputs 1. Catchment scale groundwater region classification, mapped in GIS. 2. Local scale groundwater response units, based on similar hydrogeological characteristics, mapped in GIS. 3. Inventory of potentially impacting activities and uses of groundwater with quantification of some direct and indirect uses with respect to quality and quantity. 4. Geographical position of sampling sites selected. Depth to be sampled and optimal monitoring borehole design selected. (Parameters to be sampled may be determined after RQOs are set). STEP 3: DETERMINE THE REFERENCE CONDITIONS (Natural, unimpacted conditions) Who Hydrogeologist (ecologist, hydrologist), groundwater coordinator. What Determine groundwater reference conditions How Conceptually re-establish natural (un-impacted) conditions (e.g. subtract abstractions, reconstructing recharge areas, etc.) On water quantity, quality, aquifer structure (sinkholes etc), ecological aspects (vegetation dependant on groundwater) Analyse historical and time series data for impacts. Extrapolate information from similar groundwater response units in an unaffected area. Use numerical modelling, e.g. MODFLOW to reconstruct natural groundwater conditions without human impacts (e.g. subtract abstractions, reconstruct recharge areas, etc). Extrapolate data from monitored control areas at the study sites. Outputs 3D model of natural groundwater response units and their boundaries. Typical response unit hydrographs under natural conditions. Typical range of hydrochemistry under natural conditions. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 64

72 IMPLEMENTATION OF RESOURCE DIRECTED MEASURES STEP 4: DETERMINE THE PRESENT STATUS, IMPORTANCE AND VULNERABILITY OF GROUNDWATER MANAGEMENT UNITS Who Hydrogeologist, ecologist, groundwater coordinator. What 1. Determine present status of resource units: Ecological status & resource quality; Water uses; Land uses. 2. Determine importance of resource units: Ecological importance; Social importance; Economic importance. 3. Determine vulnerability of groundwater response units in terms of aquifer integrity and water level resilience and risk of contamination or saline intrusion. How 1. Status: Expert knowledge, Open-NGDB, WMS, Local hydrochemical databases. Data from dedicated hydrocensus. 1: hydrogeological map series. 2. Importance: Discussion with catchment manager, water services providers and local ecologist(s). Consultation with wider stakeholder groups in open forum discussions. Resource economic modelling of groundwater resource values. 3. Vulnerability: Expert knowledge of aquifer integrity, drought resilience, potential saline intrusion, protective impermeable layers, transport velocities, adsorption capacity, natural decontamination processes. DRASTIC map. Estimation of landuse and potential hazards. Local hydrochemical databases. DRASTIC assessment of representative sites (Aller et al., 1987). Expert knowledge and sample testing of aquifer integrity. Monitoring data water level responses to recharge, contaminant concentrations. Hazard mapping of important groundwater management units. Outputs 3D and GIS delineation of present status of groundwater management units. Categorization of groundwater management units in terms of importance. GIS map of groundwater response unit vulnerability to contamination, salinisation, subsidence and water level declines. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 65

73 IMPLEMENTATION OF RESOURCE DIRECTED MEASURES IMPACT CLASSES FOR PRESENT STATUS: A B C D E F Natural Slightly modified Moderate modification High modification Severe modification Critical modification STEP 5: SET THE FUTURE MANAGEMENT CLASS Who Groundwater coordinator, hydrogeologist, stakeholders. What Set the management classes for each groundwater management unit. This will determine the level of protection, which should be given to the resource. Refer to Parsons, RP (2004) Groundwater Resource Directed Measures Training Manual, How Take into account the needs for: Ecosystem protection, basic human needs protection, water users protection. Base the Class on the importance and sensitivity of the resource and achievability of improvement Qualitative risk-based analysis of GIS overlay of importance and vulnerability of groundwater management units. Expert judgement on the achievability and impact of setting different management classes. Qualitative or quantitative risk-based analysis using GIS overlay of importance and vulnerability of groundwater management units. Numerical modelling of scenarios for different management classes MODFLOW, MODOFC. Outputs Management classes (A C) for groundwater management units. Associated rules for setting the Reserve, RQOs and Source Directed Controls. MANAGEMENT CLASSES: A B C Protected minimal change from reference conditions Good slightly altered from reference conditions Fair - significantly altered from reference conditions GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 66

74 IMPLEMENTATION OF RESOURCE DIRECTED MEASURES FIGURE 7: THE CATCHMENT IN THREE DIMENSIONS: AN IMPORTANT CONCEPT FOR INTEGRATED WATER RESOURCE MANAGEMENT STEP 6: SET THE RESERVE AND THE RESOURCE QUALITY OBJECTIVES Who Hydrogeologist, ecologist (aquatic), catchment manager (basic human needs). What 1. Determine the quantity and Quality of Water required to satisfy basic human needs and ecological reserve at the selected management class 2. Set RQOs for each resource unit using rules for selected classes: habitat, biota, water uses, land based activities. How 1. Reserve: Delineate areas where groundwater is providing baseflow to aquatic ecosystems and is or will be used to support Basic Human Needs. Determine groundwater-fed baseflow by hydrograph separation (Smaktin/ Herold methods) (Braune et al, 2000) and Darcy s Law Determine the quality and quantity of groundwater required for these uses in terms of water levels to maintain supply, water balance or water availability, fitness for use/ receiving environment using local expert knowledge. Determine groundwater-fed baseflow through chemical investigations, numerical modelling of links (PM Win and MODFLOW with MT3D, MODOFC, AQUAMOD) 2. RQOs: From the uses of groundwater identified in Steps 2 and 4, select key measurable indicators as RQOs to protect these uses (e.g. water levels, TDS, fecal coliforms, nitrates etc) and the level at which they should be maintained (natural, slightly modified, etc) (Colvin et al., in prep.). GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 67

75 IMPLEMENTATION OF RESOURCE DIRECTED MEASURES STEP 2 MANAGEMENT UNITS What are the direct uses of groundwater in the catchment? What are the indirect uses of groundwater in the catchment? STEP 2 MANAGEMENT UNITS List of uses STEP 4 IMPORTANCE What is the importance of these uses? What key indicators measure that these functions are being fulfilled? STEP 6 RQOs Importance of uses Key indicators STEP 5 CLASS STEP 6 RQOs According to the management class, to what level should these functions be safeguarded? Goals for management of the resource and impacting activities FIGURE 8: RESOURCE DIRECTED MEASURES: THE PROCESS TOWARDS SETTING MANAGEMENT GOALS (BRAUNE ET AL., 2000) GUIDELINES FOR GROUNDWATER RESOURCE MANAGEMENT MARCH 2004 PAGE 68

76 IMPLEMENTATION OF RESOURCE DIRECTED MEASURES Outputs GIS-based map with necessary attributes for protection of different groundwater management units. List and range of RQOs to guide management and monitoring activities. Water balance for the catchment with volumes of groundwater allocated to the Reserve and other important uses. Numerical model with optimal allocations. It should be noted that the DWAF policy with regard to Step 6 is still in a formulation stage and reference should be made to the latest DWAF RDM publications. Reference should be made to the Groundwater Resource Directed Measures Training Manual (DWAF, 2004). STEP 7: MONITORING STRATEGY Who Hydrogeologist, groundwater coordinator. What Design appropriate resource monitoring programme (See Chapter 4) How Set up monitoring systems to ensure that the Reserve and RQOs are being sufficiently maintained for the important uses of groundwater in the catchment. Outputs Design of monitoring network including position and depth of boreholes, target groundwater management units, target parameters, borehole design, frequency of monitoring, acceptable sampling, analytical and reporting procedures. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 69

77 PRIORITISATION AND IMPLEMENTATION OF SOURCE DIRECTED CONTROLS 3.4 PRIORITISATION AND IMPLEMENTATION OF SOURCE DIRECTED CONTROLS GOAL CATCHMENT MANAGEMENT AGENCIES SHOULD SEEK TO CONTROL, EITHER DIRECTLY OR INDIRECTLY, THOSE ACTIVITIES, WHICH THREATEN THE QUALITY OF GROUNDWATER IN THE CATCHMENT. In the time, that it takes you to read this sentence, three people will die because they do not have ready access to a safe and reliable supply of drinking water. (From Price, 1985 based on WHO figures). In South Africa, groundwater occurrence and use is widespread, but highly localised. It is iimpossible to protect all groundwater resources to the same degree. The NWA does not aim to prevent impacts to the water environment at all costs. A differentiated protection approach is necessary, based on the vulnerability -of regional, as well as local, importance - of aquifers. Preventing all impacts on groundwater quality, would also not allow for much needed social and economic development. Source-directed controls must therefore be implemented on a differentiated basis, which takes into account the vulnerability and the importance of the affected groundwater. For each catchment management area, some level of resource directed measure determination has to be completed as a prerequisite for the implementation of source directed controls. Implementing source directed controls The following steps need to be taken to implement source directed controls: GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 70

78 PRIORITISATION AND IMPLEMENTATION OF SOURCE DIRECTED CONTROLS STEP 1: COLLECT INFORMATION FROM RESOURCE DIRECTED MEASURES Who Groundwater coordinator, hydrogeologist What Collect information specifying the desired level of groundwater protection How Select relevant outputs from RDM procedure. Summarise information on groundwater occurrence, use and vulnerability. Outputs Key outputs from RDM process: Direct and indirect uses of groundwater Where recharge areas are located and where they are vulnerable Importance of groundwater use Present status of groundwater resources Level of acceptable risk e.g. Management Class of groundwater response units RQOs needed to measure and maintain the status of the groundwater system STEP 2: IDENTIFICATION OF SOURCES Who Groundwater coordinator, water quality manager, hydrogeologist What Collect information on the location and activities of existing potential polluters and planned developments within sensitive groundwater management class areas (e.g. classes A C). How Checklist of controlled activities (Section 37 of NWA. See end of chapter) Checklist of other activities that potentially threaten groundwater quality (See end of chapter) Land-use information from maps, known land uses, local authorities, business development agencies, local communities, national census Licence applications for controlled water uses which pose a threat to groundwater e.g. wastewater irrigation Field surveys, hydrocensus information Outputs Inventory of potentially impacting activities and responsible persons GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 71

79 PRIORITISATION AND IMPLEMENTATION OF SOURCE DIRECTED CONTROLS STEP 3: RISK-BASED RANKING OF IMPACTING ACTIVITIES Who Groundwater coordinator, hydrogeologist, risk assessment expert What Risk-based prioritisation of potentially impacting activities identified in Step 2 How Compare concentrations with pre-selected intervention levels/ screening levels (e.g. Netherlands guidelines) and only conduct the following if levels are succeeded: Identify contaminants and hazards from sources Identify pathways and travel times for contaminant transport Identify potential receptors of contaminated groundwater Perform qualitative or quantitative human health risk assessment and/or ecological risk assessment Outputs Priority list of sources which pose the greatest risk of harm to groundwater users or groundwater-dependent ecosystems FIGURE 9: RISK-BASED APPROACH CONSIDERING GROUNDWATER AS ONE OF THE PATHWAYS FOR HUMAN EXPOSURE TO CONTAMINANTS (Source: US EPA, GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 72

80 PRIORITISATION AND IMPLEMENTATION OF SOURCE DIRECTED CONTROLS STEP 4: REVIEW OF CURRENT STATUS AND MANAGEMENT PRACTICES Who Groundwater coordinator, hydrogeologist, local government pollution control officer, environmental officer at facility What Assessment of existing impacts and mitigating measures for high risk sources identified in Step 3. How Solicit information from responsible person regarding management practices and monitoring at the source Solicit information from responsible person on existing levels of contamination Site inspection of management and monitoring practices Independent assessment of contamination levels Outputs Status reports detailing impact of each high risk activity on groundwater quality Note: Steps 3 and 4 may be swapped around or they may be used iteratively, depending on the level of detail required. Quantitative risk assessment (Step 3) cannot be conducted before the levels of contamination (Step 4) are known, but it is expensive to collect data on all potential contaminants. Experience and common sense or a rapid qualitative risk assessment could be used to filter out the less urgent sites. STEP 5: SELECT SOURCES FOR INTERVENTION OR REMEDIAL ACTION Who Groundwater coordinator, pollution control officer What Identify sources requiring urgent action to stop ongoing pollution of groundwater Identify sources requiring urgent action to remedy past pollution impacts How Combine results from Steps 3 and 4 Select sources which pose the highest existing risk to human health for first priority for action Select sources which pose the highest existing risk to ecological functioning as next priority for action Identify sources where there is no responsible person (or where responsible person has not taken appropriate action to prevent or remedy impacts) for remedial action in cooperation with DWAF (See Section 6.4) GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 73

81 PRIORITISATION AND IMPLEMENTATION OF SOURCE DIRECTED CONTROLS Outputs Priority list of sources requiring action to protect groundwater quality List of sites requiring CMA intervention to enforce action by responsible person(s) List of abandoned sites requiring remediation List of sources requiring control by alternative measures e.g. local ordinance or change of land-use zoning STEP 6: SELECT AND APPLY INSTRUMENTS FOR SOURCE CONTROL Who Groundwater coordinator, legal advisor What Matching appropriate source directed controls to priority activities Communication and cooperation with - or litigation against polluters How Hierarchical approach to intervention. Increasing severity of controls to combat lack of action. Equitable application of control measures, while taking into account the need for redressing past discrimination and for economic and social development. Outputs Implementation of direct statutory controls Setting of licence conditions or minimum requirements for land-based activities Incentive programmes Supportive programmes Development and dissemination of Best Practice guidelines Hierarchy of source-directed controls DWAF advocates various levels of intervention for protection of groundwater quality by source directed controls. The intervention levels are ranked in order of preference for application, so that enforcement of statutory regulations should only be adopted in cases where self-regulation and permit conditions issued under other Government Departments fail to produce the desired pollution prevention. 1. Encouragement of self-imposed discipline 2. Ensuring that Best Practice and direct controls implemented by other organs of state such as the Department of Minerals and Energy and the Department of Environmental Affairs and Tourism satisfy the requirements of NWA 3. Regulatory control in terms of NWA and the regulations promulgated under this act 4. Development of Best Practice guidelines, which in instances may become a condition of water-use licences. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 74

82 PRIORITISATION AND IMPLEMENTATION OF SOURCE DIRECTED CONTROLS Instruments for source-directed controls: The desired level of control may be achieved by one or more of the following means: Direct statutory controls and intervention e.g. conditions imposed through permits and authorisations Incentive programmes e.g. waste discharge charges Supportive programmes e.g. the development of best practice guidelines Direct statutory controls: Direct intervention uses a command-and-control approach to elicit certain behaviour or performance from the regulated community. Examples of statutory control instruments are: National Water Act (Chapters 3 & 4) o controlled activities (Section 37) o general authorisations (Section 36 & Govt. Notice 1191) o compulsory licences (Section 43) o water use licences (Chapter 4) o pollution remediation (Section 19) o emergency action (Section 20) Regulations promulgated under NWA o e.g. Regulation 704 regarding use of water for mining Conditions imposed through permits and authorisations o licence conditions o minimum requirements (for on-site management practices) o permits issued by other authorities (e.g. mining) o standards to regulate the quality of discharges Other acts: o Water Services Act (Section 12 submission of development plans), o Environmental Conservation Act (Section 20 + regulations waste disposal), o Minerals Act (Section 39 requiring approval of an Environmental Management Programme) Other policy documents o White paper on integrated pollution and waste management for South Africa. Government Notice 227, 17 March These instruments put the water management authority in a position to pre-empt the need for reactive measures. The above and other control instruments will need to be implemented within the context of procedural and technical guidelines. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 75

83 PRIORITISATION AND IMPLEMENTATION OF SOURCE DIRECTED CONTROLS Incentive programmes: Incentives programmes give the regulated community some flexibility, but within a framework of prescribed objectives. DWAF supports self-imposed discipline and will continue to do so whenever possible. Charges for water resources management in the catchment may be used by the CMA as an instrument to encourage appropriate behaviour. Incentive approaches include: encouragement of self-imposed discipline charges for water resource management charges for waste discharge Where the regulated community can mobilise itself to develop norms and standards for a specific sector e.g. for agriculture, mining or industry, DWAF will actively participate in the process. The CMA should also be aware of opportunities for involvement in the setting of sectoral norms and standards. Supportive programmes: Advising interested persons on the protection of water resources in the WMA and the promotion of community involvement in water resource protection are among the important initial CMA functions stipulated in the NWA (Section 80). Protection of groundwater in rural and peri-urban areas, for example, would be difficult to achieve through the usual direct intervention or incentive-based instruments (DWAF, 2000). DWAF, in partnership with the CMAs, will seek to influence sectors that cannot be controlled by direct intervention or incentives through the use of supportive programmes such as: education and capacity building, including: o research and development to build capacity, to advance knowledge and understanding and to develop new and better ways of improving groundwater quality o educational initiatives to raise the level of awareness and develop skills needed to empower communities to protect their groundwater supplies best practice guidelines to educate and build the capacity of the community to regulate itself extension services to advise and assist communities to implement groundwater protection programmes GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 76

84 GUIDELINES FOR WELLHEAD PROTECTION 3.5 GUIDELINES FOR WELLHEAD PROTECTION GOAL CATCHMENT MANAGEMENT AGENCIES SHOULD SEEK TO ENSURE THAT ALL POINTS FROM WHICH GROUNDWATER IS, OR MAY BE ABSTRACTED, ARE ADEQUATELY PROTECTED AGAINST POTENTIAL POLLUTION THREATS. DWAF has proposed that the implementation of a wellhead protection programme should be a priority for groundwater quality management in South Africa. The framework for such a programme has, however, not yet been formulated. Several actions are needed before such a programme can be put into place in the Catchment Management Areas, including consultation with interested and affected parties, firming up of zoning rules and training of officials to assist communities with on-site implementation. The communities that rely on groundwater sources must play a central role in implementing their own wellhead protection plans. Approaches to the protection of the area around a borehole or spring have been developed extensively worldwide. The specific objective of these programmes is to prevent contaminants from entering the groundwater supply boreholes by managing activities on the land that contributes water to the boreholes. This is achieved by delineating a buffer zone around the borehole or well field in which potentially polluting activities are controlled. Wellhead protection has considerable economic benefits in safeguarding present and future water supplies from contamination, which could be extremely costly to remedy. Two tools are used to facilitate wellhead protection: Minimum borehole construction standards to prevent contamination entering from the surface at individual boreholes. Wellhead protection zones to control potentially polluting activities on the surface and subsurface areas through which contaminants are likely to pass before reaching a borehole or well field Minimum borehole construction standards Minimum borehole construction requirements have been proposed by DWAF, which are suitable for all production boreholes ranging from hand pumps to production boreholes in well fields. For the protection of individual boreholes, attention should be paid to (included in Level 4 documentation): Proper borehole siting Proper borehole construction and Proper borehole operation and maintenance Proper decommissioning and sealing of abandoned boreholes GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 77

85 GUIDELINES FOR WELLHEAD PROTECTION Wellhead protection zones CMAs need to be proactive in the protection of groundwater against polluters and against land uses, which pose a potential threat to groundwater, rather than simply implementing source-directed controls after pollution incidents have already occurred. Wellhead zoning can be a simple and effective means of protecting groundwater sources. Zoning defines an area around the borehole or wellfield in which certain activities are controlled or prohibited. Minimum distances should ideally be determined on the basis of travel times for the pollutants of concern. Pollutant separation distances There are no legal requirements in South Africa for the separation of potential pollutant sources from groundwater abstraction points. Recommendations have been made by Xu and Braune (1995). The following rules of thumb may be useful for the protection of individual boreholes. These are rough generalisations, based on local and international sources (DWAF, 1997; Tyson, 1993) and do not take into account the properties of the aquifer or the contaminant. It should be noted that the determination of correct pollution separation distances should be done by a hydrogeologist, especially in fractured rock terrains A Protection Zone Program was also developed by Van Tonder, 2000 to allow the efficient protection of Rural Groundwater Boreholes. The attached Protection Zone Toolbox explains the program. Protection zone I: Fencing For protection zone I (i.e. the immediate fenced area around the borehole), it is proposed that the distance of the fence around the borehole must be at least 5 m. For a borehole that is supplying water to less than say 20 persons, a well-constructed sanitary seal is regarded as enough. Quality monitoring is, however, very important. Protection zone II: Microbial and nitrate pollution A second protection zone around the borehole is proposed. The idea with this zone is to protect the drinking water from microbial (bacteria and viruses) and nitrate pollution. Many case studies have shown that bacteria usually die within 30 days after being introduced into the soil. For the delineation of this zone, in the report by Xu and Braune (1995) proposed an absolute minimum distance of 50 m between a pitlatrine and a borehole. However, in many cases in fractured aquifers, this will not be adequate. The program BPZone can be used to calculate the actual distances. Protection zone III: Hazardous elements If persistent hazardous non-degradable elements are present, the whole catchment area of the borehole must be protected. Because of the use of the word hazardous, some consideration must be given to its implications. Therefore the importance of risk assessment must be considered. The attached Toolbox program BP Zone should be used to calculate the protection zone. In primary or homogenous unfractured aquifers, boreholes should not be constructed within: GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 78

86 GUIDELINES FOR WELLHEAD PROTECTION 50 m of an on-site sanitation system 75 m of a high loading sanitation system (e.g. school, clinic etc.) 50 m of an animal burial pit or cemetery 50 m of an animal or fowl enclosure 50 m of chemical, fertilizer or pesticide storage, mixing or loading facilities 50 m of an above ground petroleum storage tank 100 m of an underground storage tank 50 m of a major road or high tension cable Only activities directly associated with collecting water should be allowed within 30 m of a drinking water supply borehole. In fractured rock aquifers, travel times may be rapid and the direction of migration unpredictable, making it difficult to apply such general rules. In such cases, it is recommended that an expert hydrogeologist undertake a site-specific investigation. Wellhead Protection Plans In the United States, a federal Wellhead Protection Programme has been established under the amendments to the Safe Drinking Water Act (1986) to protect the quality of groundwater used in public supply systems. Under this programme, the preparation of wellhead protection plans has become a legal requirement. The US Environmental Protection Agency and several state environmental agencies and educational institutions have developed guidance for local communities on the preparation of Wellhead Protection Plans. Extensive documentation of recommended tools and procedures for the design and implementation of wellhead protection plans is available from these sources on the Internet. Wellhead protection is generally required for boreholes or wellfields that are used for public water supply (e.g. where water is supplied 25 or more people). As discussed previously the attached Program BP Zone can also be used for determining wellhead protection plans. Implementing wellhead protection The following six-step method has been synthesized from the available information: GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 79

87 GUIDELINES FOR WELLHEAD PROTECTION STEP 1: GATHER INFORMATION / SET UP PLANNING COMMITTEE Who Groundwater coordinator, hydrogeologist, Water Service Provider, Water User Associations, local water users What Collect information from RDM (e.g. aquifer management classes) Collect information on water supply boreholes and wellfields (e.g. locations, drilling logs, construction details, abstraction permits) Collect available hydrogeological information reports, maps, conceptual models How Work with Water Service Providers and Water Service Authorities Hold public meetings to get stakeholder support Outputs Inventory of potential contaminants, status report on aquifer resources STEP 2: DEFINE WELLHEAD PROTECTION AREA Who Groundwater coordinator, hydrogeologist, Water Service Provider, Water User Associations, local water users What Delineate protection areas for control of potentially polluting activities around boreholes and wellfields (see delineation process at end of chapter) Define zones for varying degrees of protection How Methods for delineating protection areas are described below: distance from borehole drawdown flow boundaries travel time assimilative capacity Outputs Maps with boundaries around wellhead protection areas Physical markers for protection areas e.g. fences, public notification signboards, etc. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 80

88 GUIDELINES FOR WELLHEAD PROTECTION STEP 3: POTENTIAL CONTAMINANT SOURCE INVENTORY Who Wellhead protection committee, groundwater coordinator, water quality manager, hydrogeologist What Compile inventory of potential groundwater contamination sources in wellhead protection zones Include on-going sources, past (abandoned) sources and expected sources from projected land use Rank sources based on risks posed to groundwater How Map past, existing and planned land use in protection zones: topographical maps general land use information street maps and aerial photographs more details on location of cemeteries, waste sites, water treatment works, etc. local government planning information petroleum companies location of underground storage tanks Make an inventory of chemical and wastewater storage and disposal practices in the area: permit applications for waste sites, wastewater discharge, etc. local government/water service providers information on water and wastewater treatment works, sludge sales to farmers, municipal waste disposal sites industries and mines information from environmental officer, environmental management plans audits at chemical and agrichemical industries, dry cleaners, paint production industries, panelbeaters, scrapyards, metal refineries, medical institutions, power stations, etc. Rank sources by risk considering: affected receptors (e.g. number and demographic profile of water users supplied by a particular borehole/wellfield) toxicity of the contaminants of concern proximity of the source to the borehole, potential migration pathways and mobility and persistence of the contaminants of concern Use available data on sources from Step 2 of Source directed controls and source checklist Update inventory every two years Outputs Detailed land-use maps for wellhead protection areas Lists of potential impacts for wellhead protection areas Risk-based ranking of potential impacts GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 81

89 GUIDELINES FOR WELLHEAD PROTECTION STEP 4: MANAGING SOURCES TO PREVENT CONTAMINATION Who Groundwater coordinator, pollution control officer, with input from wellhead protection committee What Apply regulatory and non-regulatory source-directed controls to manage the threat of groundwater contamination How Review available source control instruments for existing sources: e.g. direct prosecution of polluters, pollution mitigating measures as conditions of licence approval, incentive schemes, best practices etc. Investigate and implement options for changing land use and influencing future land use planning with local government e.g. changing zoning and subdivision ordinances, review of environmental impact assessments for planned developments, source prohibitions. For the highest level of protection, investigate options for public purchase of the recharge area to prevent development, if land is still undeveloped. Investigate remediation needs for abandoned sources and implement remediation. Public education and participation in household waste management and maintenance of sanitation systems See end of chapter for principles to guide source management STEP 5: MONITOR EMERGENCY/CONTINGENCY/SPILL RESPONSE PLANNING Who Catchment manager, with input from local government / water service providers, water managers in neighbouring areas What Planning to assist with the provision of alternative water supplies in the case of long term borehole failure, a toxic spill or other damage to the groundwater resource. (Water provision in the case of short term failure of the abstraction equipment is the responsibility of the local Water Service Provider) How Identify alternative water sources within and outside the Catchment Management Area that may be used if the groundwater supply fails. Check that water service providers have adequate emergency water supply plans, including the necessary budget and infrastructure, in case of failure of their groundwater supply systems. Check that industries, transport companies, and government emergency services are informed about groundwater protection and have plans for handling chemical spills which take aquifers into account. Output Resource loss contingency plan GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 82

90 GUIDELINES FOR WELLHEAD PROTECTION FIGURE 10: THE BEST LAID PLANS OF MICE AND MEN.. CONTINGENCY PLANNING IS A VITAL COMPONENT OF CATCHMENT MANAGEMENT STEP 6: UPDATING THE WELLHEAD PROTECTION PLAN Who Catchment manager, wellhead protection committee What Update source inventory and protection plan How Update data on sources at least every two years Update emergency contingency plan every five years Maintain ongoing management of wellhead protection areas GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 83

91 REMEDIATION STRATEGIES 3.6 REMEDIATION STRATEGIES Remediation is aimed at achieving the holistic and sustainable long-term restoration of a degraded groundwater resource to a state where it is suitable for an intended future use. Financial and technical constraints prohibit the restoration of all water resources to pristine condition. For this reason, remediation strategies make use of a risk-analysis approach to rank remediation priorities. The US EPA has developed a decision-support framework for choosing sites for clean-up and setting remediation goals, which takes into account the potential harm to human health. Many of the principles and procedures of this framework, known as Risk-Based Corrective Action (RBCA or Rebeca) many be applicable for contaminated sites in South Africa. For abandoned sites in the USA, a preliminary assessment is conducted to distinguish between sites that pose little or no threat to human health and the environment and sites that may pose a threat and require further investigation. If further investigation is required, samples will be collected and analyzed to determine the risk of contamination being transported through the air or water. From these results, a hazardous ranking is then established. This ranking will determine whether the site is included on the United States National Priorities List and made eligible for Superfund cleanup, a programme which provides government funding for remediation (US EPA: Remedial measures for which the CMA is expected to be accountable include: Setting and evaluating priorities for remedial action; Clean-up of abandoned sites; and Emergency action plans or procedures for accidental spills within the catchment management area. A generic process for the remediation of contaminated land areas and deteriorated water resources is being developed by DWAF to assist those planning and embarking on remediation exercises in South Africa (Hinsch et al., in prep.). (The process had not been finalised at the time of writing and the information in this section will be viewed as provisional). The CMA will need to follow DWAF s adopted approach to remediation, once this has been formally established. The groundwater coordinator in the CMA will be involved in identifying and motivating cases where groundwater contamination requires remedial action. The need for remediation will have to be assessed on a case-by-case basis depending on: the relative risks posed by the groundwater contamination to human health and the receiving environment; the actual and expected uses of the groundwater requiring remediation; and the social and economic value of the groundwater resource established through stakeholder consultation. A clear distinction is made in the legislation (NWA) between instances of contamination where (a) responsible person(s) can be identified and those where no responsible person can be identified or where the responsible person has failed to comply with the provisions of the law. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 84

92 REMEDIATION STRATEGIES Source-directed controls are used to control instances where a responsible party is identified. o In these instances remediation (also referred to as clean-up, restoration, rehabilitation, mitigation or stabilisation) must be paid for by the party causing deterioration of the resource (Polluter Pays Principle). o Applicable legal controls for this form of remediation include: a formal letter in terms of section 19(1), for polluting activities or 20(1) for emergency incidents of the NWA licences in terms of section 21 of the NWA permits in terms of section 20(1) of the ECA. Intervention in the form of remedial action is required when there is no responsible party. o These instances become the responsibility of the state and fall under the auspices of DWAF, because of its mandate as custodian of South Africa s water resources. o Remediation initiated by DWAF will be financed from funds voted by Parliament for the specified purpose, or in extreme cases after tabling of a White Paper (Viljoen et al., in prep.). o In instances where the CMA (or DWAF) initiates remedial action in the interests of affected third parties, the NWA makes provision for the costs to be recovered later from the responsible party (Section 19(4,5)). Irrespective of the instrument of legal control, the remediation process should follow five basic steps when conducting an investigation to determine reasonable measures for the remediation of contaminated land and deteriorated water resources. These steps are taken directly from the interim 5-stage generic process for remediation, currently in development by DWAF (Hinsch et al., in prep.). GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 85 VOLUME 2: IMPLEMENTAITON

93 REMEDIATION STRATEGIES Implementation of remediation process STEP 1: INDICATE INTENTION TO EMBARK ON REMEDIATION PROCESS Who Groundwater coordinator What Notify affected parties of intention to investigate remediation and expected timeframe How Consultation with DWAF Water Quality Management Consultation with third parties affected by the pollution Consultation with other authorities e.g. Provincial Department of Environmental Affairs Indication of approximate timeframes for the execution of each stage Outputs Consensus on the initiation of remediation investigations Agreed investigation outline and time schedule STEP 2: CURRENT STATUS AND REMEDIATION OBJECTIVES Who Groundwater coordinator, hydrogeologist, geochemist, health risk specialist, ecologist What Determine current status of the site/situation Set remediation objectives in accordance with the confirmed future use of the area or resource Obtain approval for remediation objectives from DWAF and affected community How Undertake complete characterisation of the contaminated area Establish current and potential future use of the land or the resource Formulate non-value based remediation objectives in consultation with I&APs for each affected component Submit information to DWAF for evaluation Outputs Report summarising current status (see end of chapter) Outline of remediation objectives (see end of chapter) Written confirmation of objectives from DWAF GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 86

94 REMEDIATION STRATEGIES STEP 3: ALTERNATIVE OPTIONS TO MEET FUTURE USE OBJECTIVES Who Groundwater coordinator, hydrogeological and engineering specialists What Investigate alternative options to ensure that future use and objectives are achieved after remediation How Identify technologies that can achieve the clean-up objectives e.g. by literature review, comparative risk assessment Develop and screen alternatives for remediation Detailed analysis (including Risk Assessment) of remedial alternatives Preparation of action plan Outputs Preferred remediation alternative and back-up option (see end of chapter) Motivation submitted to DWAF with reasons why the technology has been chosen Action plan for short-, medium and long-term implementation of preferred option STEP 4: LEGAL AND IMPACT ASSESSMENT Who Groundwater coordinator, legal advisor, environmental assessment specialist What Investigation of legalities and impacts associated with implementation of the preferred remediation alternative How Identify residual impacts following remediation Screen to ensure compliance with EIA regulations Identify long-term legal responsibilities and liabilities e.g. change in land-ownership or land use Submit outcomes (and proof of EIA compliance, if applicable) to DWAF. Outputs Summary of legal issues and possible residual impacts DWAF will confirm with the applicant whether remediation will be authorised under the NWA (i.e. a formal letter in terms of section 19(1) or section 20(1), a water use licence in terms of section 21) or the ECA (section 20 permit) as part of the next and final stage. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 87

95 REMEDIATION STRATEGIES STEP 5: APPLICATION FOR AUTHORISATION Who Groundwater coordinator What Apply for DWAF (or DEAT) authorisation to begin remediation How Submit appropriate application forms for authorisation Submit summary report containing information by the authorising Department Outputs Issue of authorisation (permit/licence/s19/20 letter) The information requested in the summary report could include: A summary of the outcome of the site investigation, including geohydrological conclusions, stating approved remediation objectives; Public participation details relating to the confirmation of rehabilitation objectives; Implementation plan of accepted preferred option, including timeframes; Environmental Impact Assessment of such implementation; Detailed design plans of accepted remedial option; Operational plans; Maintenance plans; Water management and monitoring plans; Final rehabilitation plans; etc GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 88

96 WATER QUALITY STANDARDS 3.7 WATER QUALITY STANDARDS Water quality standards are defined limits for dissolved constituents. The water quality limit is determined by the intended use of the water and the known toxic and/or detrimental effects Variations In Quality Acceptable standards vary from country to country depending on economic prosperity, experience, climate, and geographic position. The standards tend to change with time as medical information becomes available. Sets of standards can only be considered as a guide and they are rarely legally binding Levels of Standard Water quality standards are frequently set at two or more levels: Guideline levels, the ideal concentration that should not be exceeded, and Maximum acceptable level, a concentration at which prevention, clean-up or use regulation action must be introduced The reasons for assessing water quality standards Hydrochemical studies is a necessity and should be done for the following reasons: Hydrochemical studies are done to determine the quality of the water for its intended use. Thesesare also done for water type mapping, classification and evaluation of the transport of contaminants. The evaluation of monitoring data, from potential polluting situations, has become an important part of hydrochemical studies. Water quality standards are also used as a basis for comparison. The toxic effects of most inorganic constituents are fairly well documented, however little is known about the effects of many of the dissolved organic contaminants. Over 1200 organic contaminants have been discovered in groundwater and yet only about 26 standards have had standards set The standards may change as more medical or other evidence is discovered relating to the harmful effects of a particular substance Standards are necessary To determine the usefulness of a particular water As a comparison to determine if water quality is degrading As a comparison in the evaluation of contaminant spreading In defining pollution (Adapted from Usher, 2001) GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 89

97 WATER QUALITY STANDARDS South African Water Quality Standards Water Quality Standards have been defined for all aspects of water use in South Africa. Guidelines exist for the following: Domestic Water Use Recreational Water Use Industrial Water Use Agricultural Water Use: Irrigation Agricultural Water Use: Livestock Watering Aquatic Ecosystems (After Usher, 2001) South African Water Quality Guidelines can be accessed using the Guidelines Toolbox Hyperlink Natural Groundwater Qualities The natural quality of groundwater varies from area to area in South Africa. It can range from TDS contents of less than 100mg/l to 10000mg/l for brines found in some deep lying aquifers. It should be remembered that even some of the naturally occurring groundwaters can be unfit for use due to poor natural water quality. Figure 6 shows the variance in the chemical composition of natural unpolluted groundwater for different types of geology. The variance is due to the leaching of minerals from the surrounding rocks as groundwater passes through its water cycle. Rhyolite Granite Gabbro Sandstone Shale Limestone Dolomite Schist SiO Al Fe Mn Cu Zn Ca Mg Na K HCO CO SO Cl Fe NO PO TDS ph FIGURE 11: THE VARIANCE IN THE CHEMICAL COMPOSITION OF NATURAL UNPOLLUTED GROUNDWATER FOR DIFFERENT TYPES OF GEOLOGY GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 90

98 APPENDIX A APPENDIX A IMPLEMENTING SOURCE DIRECTED CONTROLS The following detail needs to be read in conjunction with Step 2 in this method: The NWA prioritises two activities that may affect groundwater quality, by assigning them the status of controlled activities. These activities both involve wastewater disposal, namely by irrigation or artificial recharge. Section 38 of the NWA grants the Minister authority to declare other controlled activities by Government Notice. Other activities which DWAF aims to target for control (DWAF, 2000) are also listed below: Existing controlled activities: (Under section 37 of NWA) Irrigation of any land with waste or water containing waste generated through any industrial activity or by a waterwork (including water treatment and wastewater treatment facilities) Intentional recharging of an aquifer with any waste or water containing waste. Activities targeted for control: (Policy and strategy for groundwater quality management, DWAF, 2000): Groundwater abstraction de-watering and recharge Disturbance and damage to aquifers by mining and industrial activities Waste disposal and storage Diffuse sources of pollution associated with urban and rural development Underground storage tanks Internationally, various activities have been identified which can have a negative impact on groundwater quality. The following sector-based checklist provides examples for the CMAs of the most common activities, which might require control to protect groundwater quality within sensitive groundwater response units. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 91

99 APPENDIX A Checklist of land-based activities that may threaten groundwater quality: Industrial sector Production, storage and use of hazardous chemicals (A list of hazardous substances is given in the Hazardous Substances Act 15 of 1973 See box) Accidental spills of hazardous chemicals during use or transport Transport of chemicals or waste via underground pipelines Storage and disposal of solid and liquid wastes Underground storage of petroleum and other chemical products Disposal of waste ash from power generation Hazardous waste disposal by landfill Radioactive waste disposal Uncontrolled dumping Disturbance or damage to aquifers during construction Activities which alter recharge (e.g. hardening of surfaces by construction) Urban settlements Underground transport of wastewater (sewer pipes) Wastewater treatment works and maturation ponds Stormwater collection and disposal Grey water (sullage water) disposal General solid waste disposal by landfill Uncontrolled dumping Cemeteries Underground storage of petroleum products Disturbance or damage to aquifers during construction Activities which alter recharge (e.g. hardening of surfaces by construction) Excessive or uncontrolled groundwater abstraction Rural/peri-urban settlements On-site sanitation (septic tanks, soakaways, pit latrines) Grey water disposal General solid waste disposal by landfill Uncontrolled dumping Cemeteries GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 92

100 APPENDIX A Agricultural sector Land application of sewage sludge Above ground storage of petroleum products Intensive animal feedlots Inefficient use, accidental spillage or disposal of fertilizers Inefficient use, accidental spillage of pesticides, herbicides and fungicides Irrigation with poor quality water or leaching of salts during irrigation Excessive or uncontrolled groundwater abstraction Uncontrolled dumping Activities which alter recharge (e.g. irrigation, dam building, land drainage) Mining sector Disturbance or damage to aquifers by quarrying, opencast or underground mining Mine de-watering Activities which alter recharge (e.g. land drainage, tunnelling) Disposal of mining and mineral processing wastes (e.g. tailings, slimes) Disposal of waste in unused or abandoned mines Uncontrolled dumping General sources Induced intrusion of saline or contaminated groundwater into an otherwise uncontaminated aquifer Wastewater recharge to aquifers by irrigation, infiltration or injection GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 93

101 APPENDIX A Examples of Group I Hazardous Chemicals (Hazardous Substances Act, 1973) Inorganic chemicals Aluminium phosphide; arsenic and its salts; antimony potassium tartrate; antimony sodium tartrate; barium and its salts except barium sulphate; cantharidin; cyanides of potassium and sodium; hydrocyanic acid other poisonous cyanide substances fluoroacetic acid (mono), its salts and derivatives; hydrocyanic acid; lead acetate; mercuric ammonium chloride; phosphorus, yellow; strychnine; thallium; zinc phosphide; and any mixture containing any such substance Organic agrichemicals Aldicarb Azimphos-ethyl Azinphos-methyl Chlordane Chlorfenvinphos Chlorophacinone Chloropicrin Coumachlor Coumatetralyl Cyclohexamide Demeton-S-methyl Dialifor Dicrotophos Dieldrin Dioxathion Diphacinone Disulfoton DNOC Endosulfan HHDN Mecarbam Methamidophos Methidathion Methomyl Methyl bromide Methyl formate Mevinphos Monocrotophos Nendrin Omethoate Oxamyl Parathion Phenamiphos Phorate Phosphamidon Pindone Warfarin Implementing wellhead protection The following detail needs to be read in conjunction with Step 2 in this method: Delineation of the wellhead protection area There are several methods for delineating the protection area ranging from simply drawing a circle of defined radius around the boreholes to the use of complex contaminant transport modelling techniques. Where sufficient resources are available, protection areas should be defined on the scientifically defensible basis of travel times for contaminants to reach the borehole. The use of a defined distance is, however, more easily implementable and should offer adequate protection for aquifers of lower vulnerability, provided the precautionary principle is applied. In special cases, such as Class A Water Management Units, a higher level of protection is necessary and site-specific considerations may be required. Other considerations are also important, including existing land use, local goals for groundwater protection and the regulatory framework for controlling pollution sources. A wellhead protection area can also be divided into zones to allow for varying degrees of management, relative to the sensitivity of each zone to groundwater contamination. The outer boundaries may be drawn to encompass the zone of contribution, which includes all areas contributing recharge to a particular borehole. Within the outer boundaries, inner zones can be delineated using various criteria. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 94

102 APPENDIX A The zone requiring the most restrictive management in an unconfined aquifer could be designated as the area immediately surrounding the borehole or the area from which groundwater is expected to reach the borehole within a short time. Suggested criteria for delineating wellhead protection areas are: Distance from the borehole: The simplest method of delineating an area for wellhead protection involves drawing a circle around the borehole, with the idea that the land area closest to the borehole is in greatest need of protection. The radius of such a circle typically extends up to several hundred metres from a borehole. The area need, not necessarily be circular. Sometimes it makes sense to use easily recognisable landmarks such as roads or railways to define a wellhead protection zone boundary. An ellipse aligned with the flow direction, may be a more suitable shape for a protection zone. The zone may also be offset to provide a greater proportion of the protection area on the upgradient side where pollutants are more likely to travel to the borehole. Depending on the properties of the borehole and the contributing aquifer, the land immediately surrounding a borehole may or may not be part of the area from which the borehole's recharge is derived. Even in the case of a distant recharge area, however, protection of the land surrounding a borehole can help prevent borehole water contamination. If borehole casings are not properly sealed, for example, contaminants introduced at the land surface could leak into the aquifer along the borehole casing. This is a very common problem. Drawdown of the water table: A slightly more sophisticated approach to protecting the land surrounding a borehole is to delineate the zone of influence, or the land area under which the water table is lowered by borehole pumping. FIGURE 12: DIAGRAM OF WATER TABLE DRAWDOWN DURING ABSTRACTION Although protection of the area immediately surrounding a borehole will help prevent contamination from bacteria and viruses, it is unlikely to provide complete protection from chemical contaminants. Since many chemicals can be transported long distances underground without being filtered out or degraded, keeping them out of borehole water requires keeping them out of any recharge water that will eventually reach the borehole. Delineation of wellhead protection areas based on distance from the borehole or on drawdown of the water table is most appropriate for shallow boreholes in unconfined aquifers. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 95 I

103 APPENDIX A For artesian boreholes or boreholes tapping deep aquifers, a different approach is required, because the recharge areas may extend far from the borehole location. Even in such cases, however, protection of the land surrounding the borehole may help prevent problems such as the penetration of contaminants down the borehole casing. Flow Boundaries: For the most thorough protection of a particular borehole, the wellhead protection area should encompass all the land from which recharge water is derived (the zone of contribution). All water recharging the aquifer within the zone of contribution is eventually drawn to the borehole by pumping. If the rate or duration of pumping changes, then the size of the zone of contribution changes as well. Weather conditions also may affect the zone of contribution. During a drought, for example, the rate of recharge diminishes, so the area drawn upon by a borehole increases. In some cases the wellhead protection area is expanded to include land areas that are not directly within the recharge area of a borehole, but which send overland runoff into the recharge area. Some of this runoff may seep into the ground in the recharge area, along with any contaminants that have been carried along. Travel time: Another approach to designating wellhead protection areas is to base the boundaries on the estimated time of travel of groundwater or contaminants to the borehole. For example, a line can be drawn around the area from which groundwater is expected to reach the borehole within a month, a year, or any other chosen period. Since the rate of contaminant travel is likely to be equal to or lower than that of groundwater, using groundwater travel times provides a conservative estimate of contaminant travel times as well. As a rule of thumb, protection zones should encompass that portion of the recharge zone that contributes water within a five year travel time. Three methods can be used to determine the travel times. The simplest, and least accurate, is the calculated fixed radius method (CFR), which is based on the aquifer porosity and pumping rate. The radius of the circular zone for a chosen time of travel (e.g. 5 years), r, is given by the equation: r = Qt πnh Where Q= pumping rate of borehole (in m 3 /year), t =travel time (in years), n = aquifer porosity (e.g. 0.2, if unknown), H = open interval of borehole or height of screen (in metres). Analytical and numerical software models are increasingly more accurate methods of estimating travel times, but require far more data and should be used by a professional hydrogeological modeller. Assimilative Capacity: Wellhead protection areas can also be designated based on assimilative capacity, the degree to which contaminants are degraded or diluted as they travel to and through groundwater. The idea is to protect a sufficiently large area around a borehole so that any contaminants entering with recharge water will be diminished to acceptable concentrations by the time the groundwater reaches the borehole. An example of borehole protection based on assimilative capacity is the use of density criteria for planning houses with septic systems. GUIDELINES FOR GROUNDWATER RESOURCESMANAGEMENT MARCH 2004 PAGE 96

104 APPENDIX A Because the rate at which groundwater contaminant concentrations will diminish depends on the contaminant, the soil type, and groundwater flow conditions; assimilative capacity must depend both on the specific site conditions and on the properties of the specified contaminants. This approach therefore has limited use, confined to areas in which relevant data are available. Aquifer protection. All the above methods delineate wellhead protection areas based on providing protection to specific identified boreholes. A broader definition of wellhead protection areas may also be used which ensures groundwater meets drinking water standards whether or not the groundwater is currently in use. These wellhead protection areas encompass entire aquifers or aquifer management units, rather than recharge areas for specific boreholes. In this way, protection also is provided for future, as yet undetermined, boreholes and wellfield sites. Within these broadly defined wellhead protection areas, smaller areas are delineated for extra protection of individual boreholes. Implementing wellhead protection The following detail needs to be read in conjunction with Step 4 in this method: Guiding principles Two principles should be used to guide source management: Sources with the greatest potential for groundwater degradation should be subject to the most stringent controls Geographic areas where groundwater is the most important water resource or where groundwater is vulnerable to contamination should be managed more restrictively than areas of lower risk. Differentiated approach Different sources may be treated with differing degrees of control depending on travel times to the borehole. An example of this approach is to set protection zones: Sanitary control zone (30 m around individual boreholes): only activities related to water abstraction allowed. No chemical or fuel storage or use. Fenced area or locked pumphouse. One year travel zone: aggressively manage bacterial and viral contamination sources, No wastewater irrigation or disposal, no on-site sanitation, no animal activities. Five year travel zone: actively manage all chemical contamination sources. Ten year travel zone: actively manage persistent/high risk contamination sources. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 97

105 APPENDIX A Implementing remediation process The following detail needs to be read in conjunction with Step 2 in this method: The report on the current status should summarise the conditions at the site in terms of: infrastructure; reasons for the contamination; volume, extent and type of contamination (including all possible constituents based on a full inorganic and organic analysis of contaminated soils and water, as well as of the original source of contamination); and any existing and predicted future impacts of the situation or activity on all affected environmental components including: o surface water (including stormwater); o groundwater (which must be based on a geohydrological investigation, and a 3 dimensional numerical model indicating the extent of the pollution plume with regard to both organic and inorganic contaminants must be used for predictions); o air quality; and o any other environmental aspects, e.g. soils, etc.; other relevant on- and off-site issues such as stability and phreatic levels; or impacts on aspects such as ecosystems, flora and fauna, etc; emergency actions that had been taken to prevent immediate risk to human safety and health; and actions that had been taken to prevent a recurrence of similar incidents of contamination. Remediation objectives should: be formulated in consultation with the affected community be drafted for each affected environmental aspect or component ensure that the impact will be managed or mitigated in accordance with current or expected use of the resource correspond with specific RQOs determined in accordance with the specific CMS GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 98

106 APPENDIX A Implementing remediation process The following detail needs to be read in conjunction with Step 3 in this method: The preferred remediation alternative should be selected using the criteria: Ability to meet remedial objectives identified in Step 1. Ability to meet regulatory and community standards Environmental, engineering and economic criteria (Best practical environmental option) Timeframes of implementation Cost implications Ability to facilitate future use Different technologies may need to be combined over different timescales to achieve the objectives. Differences between options for the short-, medium and long term must be highlighted in the action plan, for example: Short term: investigations followed by engineering intervention; Medium term: maintenance and monitoring; Long term: continued monitoring until a predicted steady state has been achieved. Back-up options for engineering interventions (belts and braces) must also be indicated and included in the action plan for possible implementation in the event that monitoring results indicate the need for further intervention. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 99

107 REFERENCES 3.8 REFERENCES Aller, L., Bennet, T., Lehr, J.H. and Petty, R.J., DRASTIC - a standardised system for evaluating groundwater pollution potential using hydrogeological setting, US EPA Report EPA/600/2-87/035, United States Environmental Protection Agency. Braune, E., Xu, Y., Conrad, J., Van der Voort, I., Colvin, C., Le Maitre, D., Van Tonder, G., Chiang, W., Zhang, J., Hughes, S. and Pietersen, K., Comprehensive determination of the Resource Directed Measures: Groundwater component (Version 1.0). Water Research Commission Programme K5/ Carl Bro International, Guidelines for stakeholder participation in integrated water resources management in water management areas in South Africa. Ref. J. No. 123/ Colvin, C. et al., Setting the Resource Quality Objectives for groundwater. Water Research Commission Report. Driscoll, F.G., Groundwater and wells. Second edition. Published by Johnson Filtration Systems Inc., St Paul, Minnesota p. DWAF, Policy and Strategy for Groundwater Quality Management in South Africa. Number W1.0, First Edition. Department of Water Affairs and Forestry, Pretoria. DWAF, Generic public participation guidelines. Third draft. Department of Water Affairs and Forestry, Durban. Hinsch, M. et al., in preparation. Interim generic process for the remediation of contaminated land areas and deteriorated water resources. Directorate Water Quality Management. Department of Water Affairs and Forestry, Pretoria. LWVUS, Protecting Your Groundwater : Educating for Action. League of Women Voters of the United States Education Fund, Publication No. #980, Washington, DC. Internet publication: Tyson, A.W., Wellhead protection for farm wells. Water quality in Georgia. Circular The University of Georgia College of Agricultural and Environmental Sciences and the U.S. Department of Agriculture. Internet publication: extension/publications/c819-13c.html Vegter, J.R., An explanation of a set of national groundwater maps. Report TT 74/95. Water Research Commission, Pretoria. Viljoen, P. et al., in preparation. National water quality management framework policy. Directorate Water Quality Management. Department of Water Affairs and Forestry, Pretoria. Xu, Y. and Braune, E., Minimum distance as an important concept for borehole source protection in South Africa. In: Proceedings Ground water 95. Ground water recharge and rural water supply. Midrand, September Paper No. 6. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 100

108 EXECUTIVE SUMMARY CHAPTER 4 GROUNDWATER MONITORING AND INTEGRATED MONITORING NETWORKS EXECUTIVE SUMMARY Context Effective management of all water resources depends on decisions being based on facts rather than beliefs and assumptions. For this reason, monitoring and information systems are critical for successful resource management. Efficient and sustainable use of a catchment s groundwater resources cannot take place without adequate monitoring. Especially in the case of groundwater, where impacts are not immediately obvious, monitoring is required to quantify the effects of water and land use management decisions and to make adjustments where these are necessary. Groundwater in South Africa is now a public resource and water resource management is being decentralised to a catchment level, with the Integrated Water Resource Management (IWRM) principle as the cornerstone of future management. As a direct consequence of this, all national water monitoring networks should be operated in a co-ordinated manner. Roles of the groundwater coordinator Under the National Water Act of 1998 (Act 36 of 1998) (NWA) it is the responsibility of the Department of Water Affairs and Forestry (DWAF) to implement national monitoring systems, to co-ordinate with other institutions on national level and to establish guidelines for catchment level monitoring networks. The responsibility for the actual collection of water samples and data will be devolved to the regional and local level. The decentralisation means that stakeholders will be consulted when establishing the national monitoring systems, and water users may be involved in the collection of field data. This local participation will secure a feeling of ownership to the collected data, which also should be readily available to all stakeholders. CMA responsibilities One of the objectives of the NWA, and many of the other recent laws in South Africa, is the decentralisation of authority so that resources can be controlled from within the areas where they are used. The same goes for water resources information, which needs to be collected, captured, stored and managed within the Catchment Management Agency (CMA), where it is most relevant. This allows the people in the catchment management areas to take ownership of their own data, so that they can make informed decisions about issues that affect their water resources. Catchment Management Agencies should establish strategies and systems for the effective collection of useful information about groundwater resources in the catchment. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 101

109 EXECUTIVE SUMMARY Under the provisions of the NWA and DWAFs current understanding of monitoring roles, CMAs may be required to: assist DWAF (National) with the collection of data for national monitoring; design networks and carry out all the activities associated with catchment monitoring; oversee and assess information collected by water users for local monitoring; and supply available information for the purposes of the National Monitoring Systems. The NWA (Schedule 3) also gives the CMAs: the authority to require that a water user install a device to monitor the abstraction or use of water; the authority to establish links with any relevant water monitoring or management system; the authority to request records on abstraction volumes and use of water; and the power to undertake the necessary installations on behalf of any water user, and recover any reasonable cost from the user, if she or he has failed to comply with a request from the CMA in this regard. The CMA may also request that a registered water user (>10 m 3 /day): measure the quantity abstracted and record the total abstraction; calculate volumes of irrigation water; ensure establishment of additional monitoring programmes; and appoint a competent person to assess water use measurements and submit the findings to the CMA. Written records of groundwater abstraction must be submitted for database management and kept for at least five years and must be available to the CMA. Catchment Management Strategy Finally monitoring strategies should be included as a component of the overall Catchment Management Strategy (CMS). A set of guiding principles should be followed through the planning and implementation of water resource monitoring networks. Monitoring must provide the necessary information to support other CMA functions such as resource assessment, resource allocation and resource protection. Important principles that should be incorporated into the CMS are: Each component of the monitoring strategy should have a clearly defined purpose. Data collected should be relevant to the decisions that need to be taken. Monitoring should be physically and financially feasible. Data collected should be compatible with the models that use them. Monitoring should make use of the best available technologies and resources, without entailing unnecessary costs. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 102

110 EXECUTIVE SUMMARY The components of monitoring programmes should be updated periodically to take into account changing management problems, resource availability and decisionmaking models. It is important for the CMA to recognise that the resources available for water resource monitoring are likely to be limited, and the monitoring strategies should aim to make the best use of available resources. This requires efforts to prioritise those activities that provide the most critical information and promote cooperation and alignment with existing programmes to avoid duplication. Mobilising local water users for practical support and making use of appropriate technologies may also overcome the financial constraints. Cost-effective monitoring strategies should be formulated using a risk-based approach. Risk assessment tools may be used to identify those activities that pose the highest risk of harm to human health and ecosystems, or to select areas that are most vulnerable to adverse impacts for detailed monitoring, and eliminate the over-collection of data for low risk sites. In this way, unnecessary expense can be controlled. By assessing the implication of not having access to the data, the water resource manager can eliminate those data which may be nice to have but whose impact is insignificant, and concentrate on collecting the most critical data. MONITORING Groundwater-monitoring networks in South Africa will be classified in four types. Different elements of groundwater monitoring (- collection, - storage, - interpretation, - analysis, - use) will involve different institutions, and it is imperative that good linkages is established, and that all relevant role players are involved. Only via this way, can you secure motivation of the role players and sustainability of the network. Natural/Reference monitoring: Type 1 This level includes collection and analysis of groundwater data on a national scale to provide a reference / background for other measurements. The monitoring points will be selected to represent ambient groundwater conditions that are not impacted by short-term fluctuations caused by human activity. This level of monitoring will measure the natural response of aquifers to conditions over the long term and will be used for resource planning and management purposes. The physical measurements should be done by the CMAs, but the collected data must be stored and managed by the central authority. This will ensure linkage to and compliance with other national or catchment scale monitoring of hydrological systems. There also needs to be feedback to the CMAs from the national system and buy-in from the CMAs to a shared monitoring goal to ensure the collection of quality data. DWAF Head Office should provide financial support for national monitoring. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 103

111 EXECUTIVE SUMMARY Regulatory Monitoring: Type 2 This Type focuses on impacted or regional conditions specifically on control management of the functions and uses of the resource. A special subset of this level will comply to local regulatory specifically covering the initiation and later delegation of compliance monitoring for well field and production borehole surveillance. Type 2 monitoring should include both quantity- and quality monitoring. CMAs (or DWAF Regional offices, where CMAs have not yet been established) will be expected to play the lead role in catchment monitoring initiatives. Each CMA must develop and implement a regional monitoring system of the important aquifers in the catchment, which should be integrated with other relevant types of water resource monitoring, allowing for rationalisation of monitoring activities. The funding for catchment level monitoring should be budgeted for and provided by the CMAs. Specific Purpose Monitoring: Type 3 Specific aspects/issues/functions of groundwater and it s link to the surface water environment and its components are monitored. Issues like groundwater recharge and water balance are also addresses under this monitroing type. The CMA will remain responsible for the implementation and management of the data, while the water user or land owner, or a person appointed by the user, shall undertake the actual data collection. DWAF, as the central authority, will provide guidance regarding monitoring protocols and requirements, as well as audit monitoring undertaken at a local scale. Early Warning and Surveillance monitoring: Type 4 This type of monitoring programmes address point source type impacts and will have a short life time.this Type will most probably be a conjunctive effort between the CMA and DWAF Head Office and will vary from WMA to the next. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 104

112 INTRODUCTION: ROLE PLAYERS IN GROUNDWATER MONITORING 4.1. INTRODUCTION: ROLE PLAYERS IN GROUNDWATER MONITORING Monitoring is the critical first step in the effective management of water resources and is important for achieving the objects of the National Water Act of 1998 (Act 36 of 1998) (NWA). Legal requirements for monitoring, assessment and information are addressed in Chapter 14 of the NWA DWAF responsibilities The Minister of Water Affairs and Forestry is required by the NWA to establish national monitoring systems on water resources. These systems must provide for the collection of appropriate data and information necessary to assess, among other matters: the quantity of water in the various water resources the quality of the water resources the use of the water resources the rehabilitation of water resources compliance with resource quality objectives (RQOs) the health of aquatic ecosystems, and atmospheric conditions which may influence water resources. The data that will be collected will therefore relate to all aspects of the hydrological cycle. The Minister is also required to establish national information systems regarding water resources where the monitoring data will be stored, assessed and made available to the public in an appropriate manner. Groundwater information systems will be addressed in Volume 2, Chapter 5 of this document A tiered approach to monitoring other stakeholder responsibilities It is the responsibility of DWAF to establish national monitoring systems, including the development of mechanisms and procedures to coordinate the monitoring of water resources. The responsibility for the actual collection of water samples and data as well as data capture will, in all likelihood be devolved to the regional and local level. The national monitoring system will, therefore, incorporate information collected by: water users water management institutions (Water Boards, Water Services Providers (WSPs), Water Service Authorities (WSAs), Water User Associations(WUAs)) CMAs DWAF (regional offices) DWAF (national office), and other state organisations. Figure 13 shows the responsibilities of these different stakeholders. These stakeholders will be consulted when establishing the national monitoring systems. Provision is made in the NWA for DWAF to obtain any data, information, documents, samples or materials reasonably required for the purposes of the national monitoring network from any person at the written request of the Minister. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 105

113 INTRODUCTION: ROLE PLAYERS IN GROUNDWATER MONITORING Minister & DWAF (National) DWAF Regional Catchment Management Agencies Water Users WSAs/WSPs National Monitoring (ambient/ reference) Support National Monitoring Support National Monitoring Regional Monitoring (resources) Regional Monitoring (resources) National Information Systems Oversee Local Monitoring Local Compliance Monitoring NGIS WRMAIS WSAM WMS HIS/HydSys WARMS Catchment Information Systems Compliance Reporting Systems FIGURE 13: DIAGRAM OF GROUNDWATER MONITORING AND DATA MANAGEMENT RESPONSIBILITIES Monitoring of groundwater comprises several aspects such as: - identification of monitoring objectives - identification of measuring sites - collection of raw field data - analysis of information including quality control - interpretation/evaluation of data - use of information. Different institutions and individual will be involved in the different aspects of monitoring. The motivation of the involved role players and the sustainability of the monitoring is highly dependant of establishment of excellent communication between these. For the role players at local level it is extremely important that feedback is received from the more centralised institutions so that every one understands and agrees to the objectives and need for the monitoring. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 106

114 INTRODUCTION: ROLE PLAYERS IN GROUNDWATER MONITORING Natural/Reference monitoring: Type 1 Collection and analysis of groundwater data on a national scale. The monitoring points will be chosen based on conceptual models of major aquifers and selected to represent ambient groundwater conditions, not impacted by short term fluctuations caused by human activity. National monitoring will measure the natural response of aquifers to atmospheric conditions over the long term and will be used for resource planning and management purposes. Synonyms: ambient -, reference - or background monitoring Regulatory Monitoring: Type 2 Groundwater levels and water quality monitoring of water resources on a catchment or regional scale. In relation to groundwater abstraction, this monitoring will assess the groundwater response within the area of influence (its functions and uses), but not at the point of abstraction (Murray and Ravenscroft, 2002) Collection of appropriate data for the effective management of groundwater management units and to ensure compliance with resource quality objectives (RQOs). This monitoring type includes the Local Regulatory Type 2b (wellfield abstraction).catchment monitoring may further include: quality monitoring impact monitoring of non-point sources in the catchment seasonal changes (variability) impact monitoring compliance monitoring wellhead protection zone monitoring (precautionary measures) quantity monitoring impact monitoring of abstraction over an area compulsory recording of abstraction volumes impact monitoring of water level drawdown rainfall interaction compliance monitoring (where set as a condition of the abstraction licence) Synonyms: regional-, resource - or aquifer management monitoring Specific Purpose Monitoring: Type 3 Project- specific and site-specific monitoring of potential human impacts on groundwater in the areas close to abstraction or potential contamination sources. Examples of Type 3 groundwater monitoring include: quality monitoring detection monitoring (effectiveness of mitigation measures) remediation monitoring (effectiveness of clean-up) specific license conditions (eg. upcoming of saline water or sea interface) GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 107

115 INTRODUCTION: ROLE PLAYERS IN GROUNDWATER MONITORING A step-by-step approach to setting up monitoring systems suitable for catchment monitoring is given in Section 4.4. The groundwater coordinator in the CMA should play both an advisory and a motivating role in the implementation of local groundwater monitoring by water users. The monitoring requirements for each licensed user need to be clearly understood and agreed between the user and the CMA and may be stipulated in the conditions of the water-use licence. The density of sampling sites, frequency of data collection and type of measurements will be sitespecific and will need to be appropriate to the value and vulnerability of the water resource and the threat posed by the water use (e.g. groundwater abstraction, waste disposal, irrigation, etc.). Schedule 3 of the NWA assigns power and duties to the CMAs, among which are powers that may assist in carrying out the function of controlling local groundwater monitoring. These include: The authority to require that a water user installs a recording or monitoring device to monitor storing, abstraction or use of water establishes links with any monitoring or management system to monitor the storing, abstraction or use of water, and keeps records on the storing, abstraction and use of water and submits the records to the CMA The power to undertake the installation or establishment of such links as required on behalf of any water user, if the user has failed to comply with a written request from the CMA. The power to recover any reasonable cost from the water user for such installation. General authorisations for water use (Government Notice 1191) require that a person who plans to abstract groundwater, registers the use with DWAF before commencing with abstraction of more than 10 m 3 of groundwater on any given day. Registered water users are required to: measure the quantity abstracted and record the total abstraction as at the last day of each month, or calculate volumes of water irrigated using an approved method, in the case where no meter or gauge is used. The CMA, as Responsible Authority, may also request in writing that a registered water user: ensures establishment of additional monitoring programmes, and appoints a competent person to assess water use measurements and submit the findings to the CMA. Written records of groundwater abstraction will most likely be necessary for long term trend analysees and should therefore be submitted to the CMA for data maangement. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 108

116 INTRODUCTION: ROLE PLAYERS IN GROUNDWATER MONITORING quantity monitoring at individual production boreholes or wellfields recharge and discharge characterisation artificial recharge impacts on the environment quantification of groundwater-surface water interaction Level 3 monitoring is the users responsibility. It will be defined in the license or water use authorisation. Synonyms: user -, impact -, facility - or compliance monitoring Early Warning and Surveillance monitoring: Type 4 Addressing point source type impacts on groundwater. Examples may include: quality monitoring at point sources of pollution detection of pollution mitigation detection of spillage quantity monitoring impacts at artificial recharge sites impacts of canals, dams, other structures on the resource CMA responsibilities Under the provisions of the NWA and DWAFs current understanding of monitoring roles, CMAs may be required to: assist DWAF (National) with the collection of data for national monitoring; design monitoring networks and carry out all the activities associated with catchment monitoring; oversee and assess information collected by water users for local monitoring; and supply the necessary information collected at all or any of these levels for the purposes of the National Monitoring Systems. The CMA will play a lead role in catchment monitoring in the water management area and will be responsible for: the design, installation, operation, maintenance and updating of monitoring systems; data collection, data capture and storage functions; the assessment and interpretation of the monitoring data; and the dissemination of monitoring information to stakeholders and the general public. Groundwater monitoring systems will need to be established for the important groundwater management units in the catchment to collect groundwater quantity and quality data with the aim of: classifying groundwater resources assessing the status of aquifer systems e.g. checking compliance with RQOs, and determining the response to natural and anthropogenic influences. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 109

117 INTRODUCTION: ROLE PLAYERS IN GROUNDWATER MONITORING Financial support for national monitoring should be provided by DWAF Head Office. Local monitoring will, in most cases, be a prescribed condition of water use registration or licences and will have to be included in the budget of the WSP or individual water user. The funding for resource level monitoring should be budgeted for by the CMAs through CMA levies. The national groundwater-monitoring network and data collection activities will be designed and managed from DWAF in Pretoria. Participation by the CMA in activities related to national monitoring will have to be negotiated between the Head Office of DWAF and the CMA in question. GUIDELINES FOR GROUNDWATERRESOURCES MANAGEMENT MARCH 2004 PAGE 110

118 RISK-BASED, COST-EFFECTIVE MONITORING STRATEGIES 4.2 RISK-BASED, COST-EFFECTIVE MONITORING STRATEGIES GOAL CATCHMENT MANAGEMENT AGENCIES SHOULD ESTABLISH STRATEGIES AND SYSTEMS FOR THE EFFECTIVE COLLECTION OF USEFUL INFORMATION ABOUT GROUNDWATER RESOURCES IN THE CATCHMENT Guiding principles A set of guiding principles should be followed through all levels of the planning and implementation phases for groundwater monitoring networks. Examples of principles that should be incorporated into the strategy are: Planning should proceed from a general policy level downwards to a specific detailed design of each component. Each component of the monitoring strategy should have a clearly defined purpose. Data collected should be relevant to the decisions that need to be taken. Data collected should be compatible with the models that use them. Monitoring should be physically and financially feasible. Monitoring should make use of the best available technologies and resources, without entailing unnecessary costs. All components of monitoring programmes should be updated periodically to take into account changing management problems, resource availability and decision-making models. (Modified from DWAF, in prep). Monitoring strategies should be included as a component of the overall Catchment Management Strategy, which must be prepared by the CMA Monitoring objectives (The Need for Groundwater Monitoring) When developing a monitoring strategy, it is important that the purpose of monitoring be well defined and communicated to the stakeholders who need to support the monitoring efforts. It is critical that monitoring needs are established at the outset and that all participants in groundwater monitoring, from the monitoring system designer to the sampling technicians and data capturers understand the monitoring needs. No data should be collected simply for the sake of populating databases. Monitoring can be an expensive exercise and can only be valuable if the information generated is useful for purposes such as: The protection of an aquifer from damage. Over pumping causes long-term depletion of groundwater and can damage the aquifer. Water quality can decline due to over pumping. Quality monitoring will determine if the aquifer is being contaminated from sources such as pit latrines, kraals, industry, mining, waste sites, etc. Understanding aquifer flow dynamics (i.e. recharge quantification, natural flow patterns and residence times of groundwater). GUIDELINES FOR GROUNDWATER RESOURCESMANAGEMENT MARCH 2004 PAGE 111

119 RISK-BASED, COST-EFFECTIVE MONITORING STRATEGIES The protection of the quality and quantity of water required satisfying the basic human need component of the Reserve. The protection of groundwater dependant ecosystems as part of the ecological Reserve. Quantifying the effectiveness of pollution prevention measures. Quantifying the effectiveness of remediation measures. Acting as an early warning system to avoid unnecessary future remediation. The information can be used for various purposes, e.g. being incorporated in water balance calculations or models used to prepare graphic presentations that communicate useful information to politicians or communities, producing practical resource operational tools for risk management or as justification for management decisions. One of the most important goals of catchment scale monitoring will be system characterisation and resource quantification i.e. to characterise the extent and functioning of groundwater resources in the catchment. Groundwater monitoring data should be used to support decisions for taking actions that might lead to the improvement of resource protection and management. Information collected through groundwater monitoring programmes may also be useful in refining resource classification, delineating future protection zones or updating RQOs. Monitoring data is most useful when it is collected to answer specific questions, such as: Is the current level of abstraction from this aquifer sustainable? Must it be decreased or can it possibly be increased? Monitor: abstraction volumes, water levels and total dissolved solids Are the RQOs being met and if not, what are the possible causes? Monitor: parameters set for resource quality objectives Is the water quality suitable for the current or intended use of the groundwater resource? Monitor: use-based variables e.g. Table 3. Is the water quality in a particular area deteriorating or improving as a result of human activities or intervention? Monitor: site-specific or area specific indicator variables e.g. nitrate in agricultural areas, microbiology in areas with on-site sanitation, water levels and pumping volumes in wellfields. The groundwater coordinator will be expected to answer questions related to the status of the groundwater resource and the availability of water for allocation and monitoring data will be needed to support the answers. Monitoring should not been seen as a stand-alone function of the CMA, but rather as an integral part of the cycle of resource utilisation, resource assessment, and resource protection activities which enable continual improvement in the management of the water resource. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 112

120 RISK-BASED, COST-EFFECTIVE MONITORING STRATEGIES Risk-based approach Risk assessment is the process or method of determining if an activity (man-made or natural) will impact negatively on human health or the environment. Risk assessment is gaining popularity worldwide as a decision-making tool for prioritising actions, reducing expenditure and setting management targets for environmental protection. In its simplest form, risk assessment involves (sometimes qualitative or subjective) decisions on: The probability of an adverse effect occurring as a result of an activity; and The severity of the consequences if an adverse effect does occur. This combines both the likelihood that an event will take place (e.g. a spill of some toxic chemical in a recharge area and the chemical dissolving in the groundwater) and the likelihood that it will cause harm if it does take place (e.g. people drinking the water become ill). Cost-effective monitoring strategies may be formulated following a risk-based approach. In this way unnecessary expense can be controlled. The selection of monitoring stations, indicator parameters and data collection frequencies should all be guided by risk-based principles i.e. by considering what will be sufficient to know to manage the resource effectively. By answering the question: What is the implication of not having this data? The groundwater coordinator in the CMA can eliminate those data which are nice to have but whose impact is negligible or insignificant and concentrate on collecting the data most relevant to decision-making. Risk-based approaches must take into account: The source(s) of risk, e.g.: large-scale groundwater abstraction near a saline water body manufacture, storage or application of chemical substances The nature of the receptor(s), e.g.: communities (including their demographic profile and socio-economic status) groundwater-dependent vegetation or aquatic ecosystems The probability of occurrence, e.g. the combined probability of a polluting event occurring e.g. a leak or a spill the contaminant reaching the groundwater and being transported to the point of abstraction; and the contaminant being ingested by an individual from a sensitive subpopulation; and The severity of the impact, should the event occur. Risk assessment may be used to select parameters for groundwater quality monitoring, based on the intended use of the water. Different dissolved chemicals may be harmful to human health, crops and soil or aquatic ecosystems, for example. Harmful solutes that have a potential source within the recharge area should receive priority. These may include natural sources, such as high nitrate or radioactivity, as well as contamination caused by human activity. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 113

121 RISK-BASED, COST-EFFECTIVE MONITORING STRATEGIES For drinking water purposes, variables that affect health, which have a potential source in the area, may be of greater concern than the commonly tested major inorganic ions. Examples include microbiological pathogens (e.g. bacteria, viruses, parasites), toxic species (e.g. heavy metals, fluoride, nitrate), carcinogenic compounds (e.g. benzene, PAHs), or radioactivity. By deciding what is sufficient to know to meet the specific monitoring objectives, the groundwater coordinator can eliminate the taking of unnecessary measurements and reduce the costs of monitoring. This applies not only to the variables which pose a low risk to human health and ecosystems, but also to the tools used in data interpretation e.g. computerised models. Monitoring needs to take cognisance that most tools have limited accuracy and it is a waste of time and resources to collect more data than can be interpreted meaningfully. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 114

122 RISK-BASED, COST-EFFECTIVE MONITORING STRATEGIES Iterative approach Monitoring system design is not a once-off activity, but something which requires regular updating and refinement to make sure that the data collection procedures are still valid and still providing valuable information to meet the monitoring objectives. The data collection and capture to information systems must be followed by a phase of data analysis and interpretation. During this assessment phase, data gaps should be identified and the successes as well as shortcomings highlighted for feedback into the next cycle of monitoring system design as shown in Figure14. FIGURE 14: MONITORING FOR GROUNDWATER RESOURCE PROTECTION: THE FEEDBACK OF DATA COLLECTION INTO DECISION MAKING AND MORE FOCUSSED State of the groundwater resource Decision making Monitoring Information System Conceptual & qualitative understanding What if..? scenarios Compliance assurance Risk based Cost effective Goal orientated Quality assured Georeferenced Accessible GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 115

123 RISK-BASED, COST-EFFECTIVE MONITORING STRATEGIES Overcoming resource limitations The groundwater coordinator needs to accept that the resources available for monitoring will always be limited. Acknowledging these limitations, monitoring strategies should aim to make the best use of available resources, both within and outside the CMA. This requires proactive efforts to: prioritise monitoring activities which provide the most critical information; promote cooperation and coordination with other monitoring activities e.g. surface water, meteorology; align and refine existing programmes to avoid unnecessary effort or duplication of effort; streamline monitoring procedures to reduce man hours and travel times wherever possible; make the best use of existing infrastructure, especially existing boreholes; make use of local water users for financial and/or logistical support; make use of appropriate technologies; and conduct cost-benefit analyses for the monitoring network design e.g.: greater initial capital outlay (e.g. installing data loggers/telemetry systems) may be offset by future savings in the cost of collecting data, or job creation by employing local community members for monitoring tasks may provide greater benefits than the installation of expensive remote systems which are vulnerable to vandalism. On the other hand, water resource managers need to be made aware of true costs of effective monitoring and to make adequate allowance for monitoring in water resource management budgets. Water use and waste disposal charges for uses other than basic human needs must also take into account not only the costs of infrastructure and water service delivery, but the cost of managing the resource, which includes monitoring costs, often treated as externalities in water supply. Public education is important in fostering a willingness among users to pay for water resource management as well as delivery Designing a catchment Regulatory monitoring system This level focuses on groundwater resources that have been affected by human interference, but not the point of interference. In relation to groundwater abstraction, this monitoring will assess the groundwater response within the area of influence, but not at the point of abstraction (Murray and Ravenscroft, 2003). This should inlcude the functions and uses of the aquifer system. The development of a conceptual model of the groundwater resource is an essential prerequisite for the design of a groundwater observation network. Without some conceptual understanding of how the system works (e.g. where groundwater is recharged, what direction it flows in, relative rates of flow, etc.), the monitoring network is bound to be haphazard. As a first approach, the system designer needs to have at least some background knowledge on how the aquifer system is hydraulically connected to the regional hydrological cycle in the catchment. A step-by-step programme for designing a groundwater monitoring system for this monitoring is given on the following pages. The conceptual model forms part of Step 4 where the network is designed. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 116

124 RISK-BASED, COST-EFFECTIVE MONITORING STRATEGIES STEP 1: SET MONITORING GOALS Who Groundwater coordinator, monitoring team What Decide on monitoring objectives How Establish current and potential groundwater use in the catchment Establish requirements for the Reserve and Resource Quality Objectives (from RDM) Establish requirements for Source Directed Measures Establish areas and requirements for non-point source pollution monitoring Outputs Statement of monitoring goals STEP 2: ESTABLISH MONITORING STATUS QUO Who Groundwater coordinator, monitoring team What Collect information on existing systems and available financial/human resources How Collect information from DWAF, Local government, Water Users Consider: What data is currently collected? Will this be continued? What infrastructure is in place and in what condition? What historical data is available? What are the available resources and capabilities in terms of manpower, vehicles, analytical facilities, etc. Where can additional resources be obtained? Outputs Status of existing monitoring efforts in the catchment GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 117

125 RISK-BASED, COST-EFFECTIVE MONITORING STRATEGIES Outputs Develop standardised protocols for sampling, data capture, retrieval and analysis for consistency across the catchment management area (use government regulated guidance if this exists) A checklist of activities that may need consideration for the monitoring programme appears in the box below. Record of decisions on monitoring network and sampling requirements Box 1: Checklist of monitoring activities to be considered in monitoring programme design. MONITORING ACTIVITIES Network Design Sampling station location Variable selection Sampling frequency Representivity Sample Collection Sampling technique Field measurement Sample preservation Sampling point Sample transportation Real time monitoring Data Handling Data reception Laboratory Outside sources Screening and verification Storage and retrieval Reporting Dissemination Data Analysis Basic summary statistics Regression analysis Water quality indices Quality control interpretation Time series analysis Water quality models Information Utilisation Information needs Reporting formats Operational procedures Utilisation evaluation (After Sanders et al., 1987) GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 118

126 RISK-BASED, COST-EFFECTIVE MONITORING STRATEGIES STEP 5: ADDRESS SUPPORT SERVICES AND TRAINING REQUIREMENTS Who What How Outputs Groundwater coordinator, IWRM manager Establish opportunities and gaps in support for monitoring programme implementation Identify analytical service requirements: what analyses are needed? what facilities are available for analysing these can they be done in-house or contracted out? Identify information support requirements: who will handle data capture, database maintenance, data retrieval how will this be structured? see Volume 2 Chapter 5 on Information Systems Identify staff and training requirements: do field staff & data management staff have the necessary skills? can experienced personnel be appointed / technical staff be trained to undertake new monitoring functions? Organise training sessions to meet skills requirements: where possible, train staff to take a variety of samples e.g. groundwater, biological, weather measurements for collaborative monitoring efforts Network of supporting services for the monitoring programme STEP 6: SET UP QUALITY ASSURANCE/QUALITY CONTROL PROCEDURES Who What How Outputs Groundwater coordinator, monitoring team, risk expert Put procedures in place to ensure high quality data Ensure that staff collecting samples are trained to take good quality, representative samples. Ensure that sub-contractors are qualified and experienced, laboratories are accredited and both have adequate quality control procedures in place. Design quality control measures into the monitoring programme, e.g. use of duplicate samples, blanks, certified standards, etc. Design data checking routines into data capture procedures. QA/QC guidelines and procedures for various aspects of monitoring GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 119

127 RISK-BASED, COST-EFFECTIVE MONITORING STRATEGIES STEP 7: DRAW UP PLANNING DOCUMENT Who Groundwater coordinator, monitoring team What Draw up a detailed planning document covering all monitoring activities How Include: Appropriate information from steps 1-6 Framework of time and place for activities Role-players and responsibilities Opportunities for linking/support with other individuals and organisations Budget (allowing contingencies) Guidelines for subcontractors or support staff tasked with specific activities Outputs Groundwater monitoring strategy document for the catchment management area STEP 8: IMPLEMENT & UPDATE GROUNDWATER MONITORING PROGRAMME AND FEEDBACK TO DWAF Who Groundwater coordinator, monitoring team, field & data management staff What Commence monitoring and review success, feedback to DWAF office How Commence planned activities once network and supporting structures are in place Refine the strategy by conducting regular updates as more information becomes available e.g. work on a five-year cycle of information-gathering, plan development, implementation of monitoring, assessment of data, prioritisation of key areas (Figure 3). Feedback in the form of short monitoring report which gives overview of groundwater resource status and trends. Outputs Catchment groundwater monitoring programme and feedback to DWAF Regional Office GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 120

128 RISK-BASED, COST-EFFECTIVE MONITORING STRATEGIES Gather information Implement CYCLE OF MONITORING SYSTEM DEVELOPMENT Monitor Develop plan Assess data Prioritise key areas FIGURE 15: STEPS IN THE ON-GOING REFINEMENT OF THE GROUNDWATER MONITORING SYSTEM Designing a local regulatory monitoring network: This level involves monitoring of point (site) specific sources, which could be affect groundwater by over abstraction or polluting activities (i.e. quality and quantity monitoring of groundwater). Generally the user will do this level of 3 monitoring as a condition attached to the license or water authorisation. The CMA will be responsible for establishing these license requirements, as the agreement will be between them and the water user. STEP 1: SET MONITORING GOALS Who Groundwater coordinator, monitoring task team What Decide on monitoring objectives i.e. compliance to licensing or water authorisation conditions for quality and quantity of water How Establish system to collect and analyse data available for each abstraction borehole Establish requirements for the Reserve and Resource Quality Objectives (from RDM) Establish annual total abstraction and daily abstraction per source Establish ground water levels records and borehole water qualities on a time series basis Outputs Statement of monitoring goals GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 121

129 RISK-BASED, COST-EFFECTIVE MONITORING STRATEGIES STEP 2: ESTABLISH MONITORING STATUS QUO Who Groundwater coordinator, monitoring team, local user What Collect information on local borehole/aquifer system How Collect information from DWAF, Local government, Water Users Consider: What data are available for each abstraction borehole? What data is currently collected? What infrastructure is in place and in what condition? What historical data is available? Outputs Status of existing monitoring and sources in the local aquifer area STEP 3: DESIGN MONITORING PROGRAMME Who Groundwater coordinator, local user, water quality expert What Decide on requirements, sampling and data collection protocols to achieve monitoring goals How Water level monitoring should be done on a daily, weekly or monthly basis depending on the importance and vulnerability of the resource and based on the water use authorisation or licensing regulations Volumes of water abstracted should be recorded at a predetermined interval. Water level records should also be kept at the same or higher frequency. It is recommended that monthly records of abstraction values be kept for future reference and auditing. Initial water quality sampling should be done once to establish a background analysis. Murray and Ravenscroft (2003) also recommend sampling should occur before and after the rainfall season to establish seasonal trends. Water quality sampling frequency should occur based on two facets: If there is a potential polluting source nearby or if contamination already occurs in the borehole or aquifer. The water quality expert should then decide the sampling frequency (See Box 2). Outputs Record of decisions on monitoring and sampling requirements and input into licensing conditions. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 122

130 RISK-BASED, COST-EFFECTIVE MONITORING STRATEGIES STEP 4: SUPPORT AND TRAINING FOR WATER USERS Who Groundwater coordinator, IWRM manager What Establish support for water users monitoring programme implementation How Identify information support requirements fro water users Identify water users training requirements Do water users have the necessary skills? Organise training /information sessions to meet skills requirements: Outputs Network of supporting services for the water users monitoring programme STEP 5: IMPLEMENT & UPDATE GROUNDWATER MONITORING PROGRAMME Who Groundwater coordinator, field & data management staff, water user What Commence support for water users, gather information, incorporate into regional (catchment) monitoring and review success How Commence planned activities once supporting structures are in place Update local groundwater information and incorporate into Catchment monitoring Outputs Local groundwater monitoring programme STEP 6: REPORTING FEEDBACK TO DWAF REGIONAL OFFICE Who Groundwater coordinator, monitoring team, field & data management staff What Commence review on Catchment and Regional Scale How Refine the usage and allocation strategy by conducting regular updates as more information becomes available e.g. work on a five-year cycle of information-gathering, plan development, implementation of monitoring, assessment of data, prioritisation of key areas. Outputs Catchment and Regional groundwater monitoring programme GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 123 VOLUME 2: IMPLEMENATATION

131 RISK-BASED, COST-EFFECTIVE MONITORING STRATEGIES Monitoring groundwater use A major aspect of groundwater monitoring will be groundwater use. For any resource to be optimally managed, the current levels of utilisation as well as the maximum available quantity need to be known. Without monitoring, the resource manager has no support for decisions on whether the resource is over-utilised and measures are needed to limit use, or whether it is under utilised and use can be promoted. A recent investigation into groundwater use in South Africa (Seward and Baron, 2001) found that groundwater use data was a major uncertainty in water balance calculations and recommended that: {DWAF} increase awareness of the importance of collecting groundwater use data. The monitoring of use should be on a par with any other aspect of groundwater monitoring. Under the {NWA}, registration of water use greater than 10 m 3 /day is required. This amount is highly unlikely to be exceeded by boreholes for private use, but which collectively could constitute a considerable volume. Obtaining information on how much groundwater is being abstracted is always difficult, as groundwater abstraction volumes are often not measured. The installation of flow meters and the reading thereof should be strongly encouraged within catchments where groundwater plays a critical role in supporting economic activities and environmental functioning. The NWA gives the CMA the authority to compel water users to install devices to record abstraction (Schedule 3, Section 4(1)a) and water use licence conditions may also be used to enforce compulsory abstraction recording. There must also be efficient systems in place to ensure such recording devices are actually installed and maintained and to collect the information from the water users. The WARMS information system (See Volume 2, Chapter 5) is designed to store information on registered water users and will be a useful tool in this regard. The abstraction volumes measured will have to be checked against license conditions, to refine understanding of the water balance within a catchment and to assess the status of groundwater allocation. It will also provide a means of checking that licensed volumes are being adhered to. Flow meters are not always the ideal option and other innovative measures to calculate and/or estimate groundwater abstraction should be considered. Some approaches that have been attempted in the past include calculation from power consumption records or mapping irrigated land areas and calculating water use from expected crop requirements. If there is sufficient motivation for an accurate water use assessment, a detailed hydrocensus of individual users may need to be undertaken. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 124

132 SELECTION OF MONITORING SITES AND DATA COLLECTION 4.3 SELECTION OF MONITORING SITES AND DATA COLLECTION GOAL A MONITORING PROGRAMME SHOULD SEEK TO SELECT OR CONSTRUCT REPRESENTATIVE SITES FROM WHICH TO COLLECT SAMPLES AND TO GATHER ACCURATE, RELEVANT AND USEFUL DATA THAT WILL MEET THE GOALS OF THE PARTICULAR PROGRAMME Monitoring networks Sites used for the collection of groundwater data will mostly be boreholes or wellpoints 1 although springs, pits, dug wells, auger holes, piezometers 2 and surface water bodies may also be included in the network. Depending on the monitoring goals and available resources, the sampling sites may be chosen from existing boreholes or specifically constructed for the individual monitoring programme. National and catchment monitoring will make wide use of existing boreholes, while local monitoring will generally require the installation of dedicated monitoring boreholes or wellpoints. While the use of existing boreholes may save time and money in the establishment of a groundwater monitoring network, this may have to be traded off against poorer reliability of the data, especially where information on the borehole construction is not available. National networks A summary is given below of the national groundwater quality monitroing network activities as an example of a national network. Other national networks include, amongst others: The National Microbial Monitroing Programme, The Hydrological Monitoring Programme, The River Health Programme. These networks are designed by the Head Office of the Department of Water Affairs and Forestry in conjunction with the DWAF:Regional offices and the data acquisition and data management are their responsibility. 1 Boreholes are generally constructed by drilling and are usually deeper and of wider diameter than wellpoints, which are often constructed by jetting or driving casing into an unconsolidated shallow aquifer. 2 Piezometers are generally narrow diameter tubes used for the measurement of groundwater pressure levels (piezometric head) in confined or semi-confined conditions. Several piezometer tubes may be installed in a single borehole to monitor multiple piezometric levels in a layered aquifer. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 125

133 SELECTION OF MONITORING SITES AND DATA COLLECTION 1: map outlines Figure 16: Location of sampling points in the current DWAF National Groundwater Quality Monitoring Programme: (Source: Planning catchment scale networks The network designer may choose one or more of the following criteria on which to base the inclusion or exclusion of monitoring points: Sites representative of geographic distribution Sites representative of predominant land uses or changes in land use Sites representative of differing geologies and flow regimes Sites representative of main aquifer units (e.g. not perched water) Sites in close proximity to other monitoring sites e.g. surface water stations Sites representative of the use of groundwater (preference given to drinking water sources) or changes in resource development Consideration also needs to be given to factors such as: The hydrogeological value and representivity Ease of access and permission from owner The age, type and condition of the installation (borehole, gauging station, etc.) Quality of existing site information (e.g. construction, survey coordinates, etc.) For identifying and characterising groundwater resources, site selection needs to take into account the functioning of the groundwater component in the water resource as a whole. Monitoring should be focussed at the interface areas where groundwater enters or leaves the aquifer i.e. recharge and discharge (or abstraction) zones. Water balance calculations on stream flow may be useful in identifying where groundwater is a major contributor to surface water systems (and vice versa) as well as areas where little value would be gained from detailed groundwater monitoring. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 126

134 SELECTION OF MONITORING SITES AND DATA COLLECTION Planning local networks Existing production boreholes are generally not suited for local monitoring networks, which usually have a very specific goal. For detection monitoring or impact monitoring at a facility which poses a threat of groundwater contamination, the monitoring network should be designed and constructed with due consideration of (see Figure 17 for an example): Past and present activities at the site Including the location of potential pollution sources, loading rates, etc. Site-specific aquifer characteristics and geometry Primary or secondary aquifer? Confined or unconfined? Poorly constructed monitoring boreholes can provide a pathway for contaminants to reach a confined aquifer. Location of structures that may act as flow barriers. Location of major fractures which may allow preferential flow (These may require a geophysical survey). Flow rates and attenuation capacity Risk assessment Human health risk and ecological risk. Location of the nearest potential receptors. Hazardous nature of the pollutants. Travel times to reach receptors. Attenuation capacity of the aquifer for specific contaminants. Reference conditions At least one monitoring point should be located up gradient of the potential source to monitor the condition of groundwater entering the facility Area extent of pollution plume(s) Down gradient monitoring points should be aligned both parallel and perpendicular to the dominant flow direction to allow for plume delineation and investigation of migration and attenuation rates. The network should be expanded as the plume migrates and should extend beyond the edges of the plume. Vertical stratification Multilevel sampling may be needed for layered aquifer systems Best practice is to construct clusters of boreholes at each monitoring point with an individual borehole for each major aquifer unit. Other units intersected by the borehole should be sealed off with bentonite. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 127

135 SELECTION OF MONITORING SITES AND DATA COLLECTION N Legend W S E #S Vi-07 Existing landfill cells New cell No.3 #S Boreholes Vi-10 #S $T Vi-09 #S Vi-03 $T Infilled boreholes Stormwater drains Vi-18 #S #S#S Vi-17 Vi-16 $T Vi-02 Road Site boundary Buildings Ponds Vi-11 #S#S Vi-13 Vi-14 Vi-12 #S#S #S Encapsulation Cells #S Vi-15 Old Evaporation Ponds Vi-04 #S #S Vi-01 Vi-05 #S Vi-BK Geology Aeolian sand dune Mudstone meters FIGURE 17: EXAMPLE OF A LOCAL GROUNDWATER MONITORING NETWORK AT A WASTE DISPOSAL SITE Monitoring borehole design and construction A competent hydrogeologist should do monitoring borehole design and construction. The design will vary based on the use of the monitoring borehole. Fetter (1993) and Driscoll (1986) provide a number of references for efficient monitoring borehole design. In Level 4 monitoring borehole design and construction are explained Monitoring point density The density of monitoring points depends on financial resources and the desired level of precision. Local monitoring networks will need to be designed around local goals and priorities. Several approaches may be taken for the selection of minimum monitoring point density for national and catchment monitoring (DWAF, in prep, 2004) including: Selection based on geographical coverage, to provide a guideline for investment and planning according to aquifer units (or surface water sub catchments); aquifer flow patterns including recharge and discharge areas; aquifer area; volume of water abstracted; or regional priorities and RQOs GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 128

136 SELECTION OF MONITORING SITES AND DATA COLLECTION Some catchment and national monitoring points may be combined to provide better coverage, while avoiding duplication of effort. Factors to be considered are: the distance over which significant variation is expected; compatibility with current monitoring practices and densities; and the combined density of surface water and other monitoring in conjunction with groundwater monitoring Selection based on aquifer importance, including issues such as Main water users (basic human needs, bulk water supply, mine dewatering, irrigation, stock watering) Abstraction rates vs. water allocations Aquifer potential and sustainability Following a differentiated approach, monitoring densities will be high for aquifers of high importance and low for minor aquifers. Statistical selection based on observed aquifer behaviour Representative monitoring points are selected based on the statistical correlation of their attributes with those measured across the aquifer on a larger scale. Eliminating those points that are not required to achieve the desired level of accuracy optimises network density. For example, a mathematical surface may be fitted through all observed water level values in an aquifer unit and then individual boreholes selected for representivity, based on the mean square error of the regression of the overall water level trends against the water levels of the specific boreholes. Limitations of this approach include: Considerable amounts of data are required before unnecessary points can be eliminated. The reduced set of monitoring boreholes may not be adequate to monitor departures from normal aquifer behaviour due to local influences. Variations in local geology and the hydraulic characteristics of the aquifer, specifically in South Africa s complex fractured rock aquifers, may severely limit the applications of the technique. For the initial development of a groundwater monitoring network, the following recommendations are made: Three observation points (each with a particular set of sensors) should be located in the recharge zone, according to the conceptual understanding of the aquifer. Three to four observation points should be located in the intermediate flow zone between recharge and discharge areas. This could be a complex issue in secondary aquifers due to preferential flow paths and natural barriers such as dykes and nonpermeable zones. Additional monitoring points may be needed before these are established. Monitoring in the discharge zone should cover all major natural outflows (baseflow to surface drainage systems, springs, wetlands, evaporation zones, etc.) All anthropogenic discharges e.g. abstraction and mine dewatering should also be monitored. Monitoring networks for Southern African Development Community (SADC) countries range in density from over 900 water level monitoring stations (100 with autographic recorders) in Namibia and 500 stations in Botswana, both of which are strongly groundwater-dependent, to countries where no official groundwater monitoring occurs. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 129

137 SELECTION OF MONITORING SITES AND DATA COLLECTION Frequency of measurement Selection of monitoring frequency depends on: Intended use of the data Rate of response of the aquifer to transient events Water use monitoring Abstraction monitoring is measured by flow meter, which generally operates on a continuous basis. The total volume abstracted is then accumulated for a selected time period e.g. hourly, daily, weekly or monthly. The recording interval will depend on the intended use, e.g. monthly abstraction records are sufficient to determine seasonal groundwater use patterns in an area, while hourly records will provide detailed information on daily pumping cycles. Annual abstraction totals are generally a minimum requirement for water balance calculations, although it is recommended that more frequent recording take place. Water level monitoring Continuous water level recording using automatic recorders, for example, show that some boreholes may respond rapidly to recharge events over a time scale of a few hours, while other boreholes may only show long-term seasonal fluctuations. A short pulse of contamination in a fast flowing aquifer may be missed completely if samples are only collected once annually during the dry season. However, if the purpose of monitoring is to measure long-term trends in catchment water levels, then biannual monitoring may be enough. For long intervals between measurements in a fluctuating system, not only the frequency, but also the timing of the measurements becomes important. Box 2: Recommended frequencies for water level monitoring to fit the aims and resources of national, catchment and local monitoring NATIONAL MONITORING (eg. Basic/Reference Type) Aim: Assessment of groundwater resource characteristics and short and long-term responses to climatic influences on a national scale. Resources: National funding, regional support from DWAF & CMAs, dataloggers and automatic recording and sampling devices. Intended frequency: Daily readings (data loggers) or Continuous readings (automatic recorders) Data collection interval will depend on storage capacity of recording devices Regular, on-going recording GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 130

138 SELECTION OF MONITORING SITES AND DATA COLLECTION CATCHMENT MONITORING (eg. Regulatory monitoring) Aim: Assessment of groundwater resource quality on a catchment/aquifer scale. Monitoring responses to human activities e.g. abstraction and contamination. Resources: CMA funding, mainly from water use- and waste discharge charges. May have some support from DWAF Regions. Water sampling by hand. May have access to waterlevel recording devices. Recommended frequency: Six times per year on average Higher frequency for boreholes with pronounced fluctuations Lower frequency for confined primary aquifer systems Regular monitoring for observing long-term trends Irregular monitoring for observing impact of sporadic events e.g. floods/ land use change Continuous recording of water levels over the first full hydrological cycle is recommended. This allows characteristic behaviour of the borehole to be established and informs the selection of a suitable long-term measuring frequency. LOCAL MONITORING (eg. Specific Puropse, Early Warning&Surveillance) Aim: Assessment of groundwater impacts on a local, site-specific scale Resources: Local user funding. Public funding for municipal wellfields (Municipal rates and taxes). Industry funded for compliance monitoring by potential polluters. Monitoring may be contracted out to consultants. Resources will largely depend on local socio-economic conditions Recommended frequency: Will depend on the use of the data and local flow conditions Water level measurement and sampling frequencies for waste site groundwater monitoring are recommended according to site classification in the Minimum Requirements for Water Monitoring at Waste Disposal Sites (DWAF, 1998) Water level measurements should be taken before pumping each time groundwater quality samples are collected at local pollution source monitoring networks Monthly records of abstraction volumes are a legal requirement for registered groundwater users. Water level records should also be kept at the same or higher frequency. To form a functional part of any monitoring network, the minimum frequency of observation of water levels in boreholes should be two times per year, ideally timed to coincide with annual peaks and troughs according to seasonal climatic changes (DWAF, in prep 2003.). GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 131

139 SELECTION OF MONITORING SITES AND DATA COLLECTION TABLE 3: RECOMMENDED FREQUENCY OF WATER LEVEL MEASUREMENTS BASED ON SOUTH AFRICAN AQUIFER TYPES (AFTER DWAF, IN PREP, 2004.) AQUIFER CATEGORY Low storativity aquifers e.g. Karoo sedimentary, Younger granites, Granite-gneiss complexes High storativity aquifers e.g. dolomites, TMG, Primary/coastal, Kalahari Group, Deep aquifer systems, Archean granites Minor aquifers NATIONAL MONITORING Daily Weekly None CATCHMENT MONITORING LOCAL MONITORING Groundwater quality monitoring Monthly Bimonthly Six monthly Daily, depending on the impact of abstraction, population and climate condition Weekly/monthly Monthly Groundwater is a slow-moving medium and dramatic changes in the groundwater quality are not normally encountered within hours or days as is found in surface water. The frequency at which groundwater samples are collected for quality analysis will depend on the sampling objectives and the aquifer behaviour. Water quality monitoring is generally conducted at a lower frequency than water level (quantity) monitoring, chiefly because of the time and costs involved in sample collection and analysis. National groundwater quality monitoring is very limited in other Southern African states and samples are usually analysed only when new boreholes are drilled. National or catchment monitoring of resource quality away from potential sources of pollution, it is suggested that samples should be collected twice per year. For an aquifer that responds to seasonal rainfall patterns, these should correspond to the peaks and troughs of the water level measurements. Local monitoring intervals should be more frequent, usually monthly or quarterly, depending on the type of impact anticipated and the rate of migration or decay of contaminants. The document Minimum requirements for water monitoring at waste management facilities (DWAF, 1998) gives the following advice for groundwater sampling frequency, which is considered valid for local monitoring at other potential pollution sources: Initial sampling should be done at a frequency high enough to obtain statistically valid background information. For any long-term monitoring facility, three initial sampling exercises, all within 90 days, but not less than 14 days apart are suggested. Depending on the variation amongst these values, future sampling may be planned. A three monthly sampling frequency will in most instances be sufficient. Boreholes used for public drinking water supply should be sampled weekly or even daily, if possible. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 132

140 SELECTION OF MONITORING SITES AND DATA COLLECTION Data to be collected The types of data collected during groundwater monitoring can usually be distinguished as: Data related to quantity Water levels, flow rates, pumping rates, rainfall and abstraction volumes Data related to quality Physical measurements (e.g. temperature, electrical conductivity) Chemical measurement (e.g. ph, alkalinity, species concentrations) Specialised measurements (e.g. stable isotope ratios) The selection of which data to collect, particularly in the case of chemical variables, where hundreds of different species could be analysed, can be: Use-based Select determinants which affect the fitness of the water for a particular use Source-based Select determinants or indicators which reflect the impact of known point and non-point sources in the area Use risk-based prioritisation to select determinants which have the greatest risk of damaging human or ecosystem health Resource-based Select determinants which help to quantify various aspects of the behaviour of the aquifer and the relationship between them. Monitoring programmes need to collect and store once-off data, relating to the aquifer and the monitoring network and data that vary in time or space, relating to the conditions of the groundwater system. A list of the different types of data that may be collected is given in the box below. Chemical and microbiological variables (also referred to as parameters, analytes or determinands) should be selected before sampling as the ability to analyse a sample and the accuracy of the result may be affected by the sampling practice, sample volume, container type and method of storage or preservation. GUIDELINES FOR GROUNDWATERRESOURCES MANAGEMENT MARCH 2004 PAGE 133

141 SELECTION OF MONITORING SITES AND DATA COLLECTION TYPES OF GROUNDWATER MONITORING DATA Site constants Once-off data pertinent to the construction and geometry of the groundwater monitoring network Coordinates of monitoring points (X, Y, Z) and method of measurement and accuracy of coordinates Coordinates of point sources and sinks of water (production boreholes, springs, etc.) Geometry of the aquifer system (lateral boundaries, aquifer outcrops, surface water bodies) Elevation of datum (usually the top of the borehole casing, used for water level measurements) Elevation of ground surface Elevation of top and bottom of aquifers and aquitards Elevation of top and bottom of perforated sections of borehole casing Diameters and depths of boreholes Geology and lithology Constant parameters Slowly varying and slowly accumulating data describing the characteristics of the hydrogeological system. Hydraulic parameters used in groundwater flow models e.g. hydraulic conductivity, transmissivity, storage coefficients Attenuation and retardation factors used in mass transport models e.g. dispersivities, partition coefficients Variable parameters Dynamic data representing the status of the system at a particular point in time 3 Piezometric head (groundwater level) Pumping rate/ injection rate Spring flow rate Abstraction volume Surface water level (for water bodies in hydraulic connection with aquifers) Precipitation depth over an area Rate of water abstraction from overlying aquifers Rate of application of irrigation water or liquid effluents Temperature Electrical conductivity ph Concentrations of chemical elements, ions and compounds (macro and trace elements) Stable and radioactive isotope concentrations Microbiological variables User information Owners details, access information, abstraction equipment Relative location of potential pollution sources Licence information Water allocated volumes The following lists of suggested water quality parameters may be useful in selecting variables to be measured for groundwater quality monitoring programmes: 3 Variables, particularly water quality variables, can also represent a particular point in space in the case of vertical logging down the borehole. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 134

142 SELECTION OF MONITORING SITES AND DATA COLLECTION Use-based selection of variables The South African Drinking Water Quality Guidelines (DWAF, 1996) provide detailed information on the variables that affect the quality of water for a range of end uses. Guidelines are available for: Volume 1: Volume 2: Volume 3: Volume 4: Volume 5: Volume 6: Volume 7: Domestic use Recreational use Industrial use Agricultural use: irrigation Agricultural use: livestock watering Agricultural use: aquaculture and Aquatic ecosystems. Toolbox South African Water Quality Guidelines has links to the above information. Drinking water is also covered in a South African Bureau of Standards specification, SABS 241: 2001, which may, in future, become enforced for drinking water quality testing by regulation under the Water Services Act. TABLE 4: USE BASED SELECTION OF GROUNDWATER QUALITY MONITORING VARIABLES Use Domestic Livestock Irrigation Industry Minimum variables Should be included every sampling run ph EC TDS (calculated) Microbiology ph EC TDS (calculated) Microbiology ph EC TDS (calculated) ph EC TDS (calculated) Alkalinity Additional variables Should be included for initial sampling (to establish background conditions) and may be included selectively or less frequently on later runs Major ions Nutrients Trace elements Fluoride Iron DOC Cyanide Viruses and parasites Taste Odour Colour Hardness Scaling/corrosio n Turbidity (SABS 241:2001 * ) Major ions Fluoride Nitrate & nitrite Arsenic Copper Molybdenum Selenium Boron Iron Major ions Scaling/corrosio n SAR (calculated) Aluminium Beryllium Boron Chromium Cobalt Copper Fluoride Lithium Iron Manganese Nickel Selenium Zinc Hardness Scaling/corrosio n Chloride Iron Manganese Silica Sulphate Suspended solids COD GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 135

143 SELECTION OF MONITORING SITES AND DATA COLLECTION Use Domestic Livestock Irrigation Industry Conditional variables Should be included every run if sources are present or problems expected Nitrate Fluoride Iron Arsenic Uranium Sulphide Cyanide Phenols VOC Pesticides Radioactivity Trace elements Pesticides Food crops: Cadmium Lead Faecal coliforms Leaching risk: Inorganic nitrogen (nitrate & nitrite, ammonium) * Requirements for monitoring may be set by Government regulations in future. Source-based selection of variables for groundwater protection monitoring Depends on requirements for each industrial process The following lists give some general suggestions for variables to be analysed when undertaking local monitoring near potential sources of contamination. A site-specific and source-specific approach, which considers both the content and volume of the waste and the mobility of the contaminants, is recommended when selecting appropriate variables for monitoring. Indicator variables are recommended here as an inexpensive option for regular monitoring and pollution tracking, while the more extensive variable list need only be considered for comprehensive studies or infrequent pollution characterisation. It is best to perform a comprehensive analysis before commencing a potentially polluting activity to provide baseline data for existing concentrations in the aquifer. TABLE 5: SOURCE-BASED SELECTION OF GROUNDWATER QUALITY MONITORING VARIABLES Source/ activity Indicators Variables Sewage works and onsite sanitation/ sludge application ph, EC, potassium, nitrate ammonium, coliforms ph EC Nitrate & nitrite Ammonium TKN Phosphate DOC COD Microbiology faecal coliforms, parasites, viruses Potassium (Nitrogen isotopes) Industrial wastewater: Trace elements e.g. Fe, Mn, Al, Zn, Cu, Cd, Ni, Pb Cemeteries ph, EC, potassium, coliforms ph EC Nitrate & nitrite Ammonium TKN Phosphate DOC Microbiology Potassium Petrochemical processing/ fuel storage tanks ph, EC, DOC ph EC Alkalinity DOC BTEX or VOC Trace elements: Cd, Cr, Cu, Fe, Ni, Zn, V Specific compounds in storage + degradation products GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 136

144 Source/ activity Agriculture fertilizer application SELECTION OF MONITORING SITES AND DATA COLLECTION Agriculture intensive animal feedlots Agriculture pesticide application Indicators ph, EC, nitrate ph, EC, coliforms Specific pesticides Variables ph EC Alkalinity Nitrate & nitrite Ammonium Potassium Sulphate (Nitrogen isotopes) ph EC Alkalinity Nutrients Microbiology faecal coliforms Potassium (Nitrogen isotopes) VOC Pesticides known to be in common use in the catchment. (Atrazine is the most studied & the only one mentioned in the SA water quality guidelines) Source/ activity Mining activities /acid mine drainage Waste disposal sites Indicators ph, EC, sulphate ph, EC, chloride, DOC ph, EC Variables ph General: EC ph Acidity or Alkalinity EC Sulphate Acidity or Alkalinity Trace metals (depend Major ions on type of ore & Nutrients processing): e.g. Boron Fe, Mn, Zn, Cu, Pb, Cr, Ni, Cd, Co, V U, Radioactivity Hg, As, cyanide Source/ activity Indicators Variables Source/ activity Industry chemical Specific to the product & industrial process. Specific to the product & industrial process. ph, EC, Alkalinity Inorganic &/or organic contaminants Industry textiles & tanneries Hazardous: include TOX/VOX PAH Phenols VOC Toxic trace elements Industry pulp & paper ph, EC, DOC ph EC Alkalinity COD DOC Trace elements: Cr, Cu, Pb, Hg, Ni, Zn Industry Coal-fired power stations Indicators ph, EC, DOC ph, EC, sodium, sulphate Variables ph EC Colour COD DOC Trace metals: Cr ph EC Major ions, particularly sodium and sulphate Trace elements: Cr, Zn, As Industry food processing Specific to the industrial process. ph EC Major ions Nutrients Microbiology Trace metals: Se, Ag, Zn Industry metal works and plating ph, EC, sodium ph EC Trace metals: Cd, Cr, Cu, Co, Fe, Ni, Pb, Hg, Ag, Se, Sn, Zn Cyanide or other specific complexing agents Fluoride (Al production) Commercial dry cleaning ph, EC, DOC ph EC Tetrachloroethene (PCE) and breakdown products Trichloroethene (TCE) Dichloroethene (1,2- DCE) Vinyl chloride (VC) GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 137

145 Box 4: Definitions of grouped water quality variables SELECTION OF MONITORING SITES AND DATA COLLECTION Major ions = Major cations and anions commonly found in natural waters, including sodium, potassium, calcium, magnesium, chloride, sulphate and bicarbonate (often measured as alkalinity). Minor species = Minor ions and elements commonly occurring water, including lithium, fluoride, silica, iron, bromide, barium, strontium, sulphide, cyanide Trace elements = Aluminium, antimony, arsenic, cadmium, chromium (total and hexavalent), cobalt, copper, lead, manganese, mercury, nickel, selenium, vanadium and zinc are the most commonly analysed trace elements Heavy metals = Cadmium, chromium (total and hexavalent), cobalt, copper, lead, manganese, nickel, vanadium and zinc i.e. trace elements excluding aluminium and non-metals or metalloids. Nutrients = Various forms of nitrogen, phosphorus and organic carbon e.g. nitrate (and nitrite), ammonium, organic nitrogen (measured as total kjeldahl nitrogen), (ortho) phosphate, dissolved organic carbon, chemical Resource-based groundwater monitoring variables Regular monitoring of groundwater quantity on a catchment and national scale will involve measurement of groundwater levels (piezometric head) in the boreholes, wellpoints, wells and piezometers that comprise the water level monitoring network and the measurement of groundwater use within an area. Measurements of spring flow or seepage rates and stream flow or lake levels may also be included, particularly where surface- and groundwater bodies are known to be linked. It is envisaged that rainfall volumes and EC, chloride, oxygen-18 and deuterium in both groundwater and rainwater may become part of national groundwater monitoring initiatives, because of their usefulness in recharge calculations. Groundwater level fluctuations are the most important source of information for analysing aquifer dynamics and for diagnosing the influence of environmental change (De Vries, 2000). Valuable information on the recharge characteristics of an aquifer can be obtained from simple measurements of groundwater level behaviour and rainfall volumes and these variables should be included as standard in catchment monitoring programmes. Groundwater abstraction volumes need to be measured in conjunction with groundwater levels to quantify the impact of pumping. Catchment groundwater quality monitoring programmes generally include ph, EC, and major ions. Temperature, nutrients and selected minor and trace species are also sometimes included. Nitrate and fluoride, in particular, are commonly measured because of their potential to affect human health if present in high concentrations in drinking water. Iron and manganese are useful for tracking potential clogging and staining problems and silica for geochemical modelling. Minor species and trace elements may be selected for monitoring based on the results of initial baseline screening of a wide range of variables at the start of the monitoring programme. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 138

146 SELECTION OF MONITORING SITES AND DATA COLLECTION Selection may also be based on their suspected occurrence related to either the local geology or activities in the catchment. The impact of non-point sources of groundwater pollution is measured on a regional rather than a local scale and potential non-point sources should be taken into account when designing catchment groundwater monitoring programmes. Microbiology is seldom included in catchment groundwater monitoring, often because of the logistical problems of sample contamination and the short time span allowed between sampling and analysis. Hydrological and hydro chemical tools are available that may help elucidate the dynamics of groundwater systems, including recharge and discharge patterns, surface water interactions, groundwater age and flow paths, depths of circulation, etc. These tools often require specific data, which will generally be collected and analysed during a short-term study of the aquifer behaviour. In some cases, it may be beneficial to incorporate a few of these variables into long-term catchment monitoring programmes. These can then be used for resource evaluation or as indicators of changes in the dynamics of the aquifer as a result of human impacts. Examples of tools for resource evaluation and their data requirements: Water balance - used to determine recharge volumes, aquifer storage, sustainable yields, etc. Volumes of rainfall, evapotranspiration, abstraction, discharge to sea or surface water, stream flow gains and losses, changes in water levels, soil moisture content Example = cumulative rainfall departure (CRD method) used to calculate recharge using rainfall, abstraction and discharge volumes and groundwater levels Hydrograph separation used to determine baseflow component of surface runoff which is groundwater-fed Stream flow volumes as a function of time (hydrographs) Oxygen-18 and deuterium isotope data may improve confidence. Chloride balance used to calculate the percentage of rainfall that contributes to groundwater recharge, if no chloride is contributed by the soil/aquifer Rainwater and groundwater chloride concentrations Stable isotopes - used for tracing recharge and pollution sources, surface water/groundwater interaction, flow paths, reactions with minerals Oxygen-18 (δ 18 O) and deuterium (δd) in rainwater, surface water and groundwater Carbon-13 (δ 13 C) for tracing inorganic/organic carbon sources and correcting 14 C age data Nitrogen 15 (δ 15 N) for differentiating nitrate sources e.g. fertilizer, natural nitrogen fixing or animal waste. Age dating used to trace flow paths and determine sustainable yields Radioactive isotopes e.g. 14 C, tritium or chlorofluorocarbons (CFCs) GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 139

147 SELECTION OF MONITORING SITES AND DATA COLLECTION Geochemical diagrams - (e.g. Piper, Durov) - used to trace flow paths and mixing of water sources Major ions, EC or TDS Chemical mass balance used to trace flow paths, mixing of waters and reaction with soil and aquifer minerals Major ions, minor species, stable isotopes, soil and aquifer mineralogy, water temperatures Geothermometers used to trace groundwater temperature maximum and depth of flow Water temperatures, silica, sodium, potassium, magnesium, calcium, lithium, sulphur isotopes. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 140

148 A STEP BY STEP APPROACH TO GROUNDWATER SAMPLING AND MONITORING 4.4 A STEP BY STEP APPROACH TO GROUNDWATER SAMPLING AND MONITORING At present, there are no prescribed monitoring procedures for groundwater in South Africa, but the National Water Act makes provision for the Minister of Water Affairs and Forestry to make future regulations regarding: Guidelines, procedures, standards and methods for monitoring, and The nature, type, time period and format of data to be submitted for the national information systems. Any new regulations made will be published in the Government Gazette. South African guidelines covering various aspects of water quality sampling have been published by the South African Bureau of Standards as the SABS ISO 5667 series. These include: Part 1: Guidance on the design of sampling programmes (1980) Part 2: Guidance on sampling techniques (1991) Part 3: Guidance on the preservation and handling of samples (1994) Part 11: Guidance on sampling of groundwaters (1993) The most easy-to-follow and comprehensive sampling guide available in South Africa at present is a manual published by Weaver, J. (1992). This manual covers aspects such as: Planning a sampling run Determinant selection Field determinants Quality assurance Preparation of a monitoring programme guide Sample records and chain of custody Sample containers and sample preservation Water-level measurement Sample collecting devices Purging the borehole Filtering devices Flow-through cell Multiple level sampling Protective clothing Decontamination Sampling of springs, wells and seeps. Additional sources of information on groundwater sampling, including sampling for specialised variables, such as isotopes, are given in the reference list (see detail in Level 4). GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 141

149 INTEGRATION OF GROUNDWATER MONITORING WITH OTHER MONITORING NETWORKS 4.5 INTEGRATION OF GROUNDWATER MONITORING WITH OTHER MONITORING NETWORKS, ESPECIALLY SURFACE WATER AND HYDRO- METEOROLOGICAL MONITORING Integration of groundwater monitoring with other monitoring activities in the catchment should be approached proactively and incorporated into the design of monitoring programmes at an early stage. Provision is made for the integration of other media in the early information gathering and coordination steps of the method set out in Section 2.6. Monitoring activities need to be coordinated at a high level in the CMA so that the data sets are consistent and complementary. Groundwater monitoring must be part of a suite of monitoring activities, which can then feed valuable information into the other CMA functions, such as resource assessment, water use allocation or the selection of best alterative water supply options. Figure 18 illustrates various main components that should be included in an integrated monitoring system for a catchment. A B C A = Meterological: precipitation and temperature B = Microclimatic: evapotranspiration, soil moisture C = Groundwater: water levels and quality D = Surface water: river flow & quality, including baseflow B B C D FIGURE 18: MONITORING COMPONENTS FOR INTEGRATED CATCHMENT MONITORING SYSTEMS. (MODIFIED FROM SCOTT AND LE MAITRE, 1998) In order to understand the role of groundwater in the full water system of the catchment, the groundwater coordinator needs to balance groundwater inflows and outflows with other components of the water cycle. This requires an understanding and quantification of those various components, and means that much of the monitoring focus will be placed on the interface areas of recharge and discharge in the catchment. Raw data for surface water systems is available, but in most cases a better understanding will be reached through working side-by-side with catchment hydrologists. Currently, hydrological data are available from the DWAF Directorate Hydrological Services. These data reside in the Hydrological Information System (HYDSYS) described in Volume 2, Chapter 5. Information and access to this data is available on the website /hydrology. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 142

150 INTEGRATION OF GROUNDWATER MONITORING WITH OTHER MONITORING NETWORKS Flow is measured on a continuous basis at more than 800 stream flow stations and at approximately 220 flow meters on pipes. Water levels are monitored at about 250 dams and inflows for about 200 of these dams are calculated. Rainfall data is collected at more than 360 sites and evaporation at about 350 sites. Water quality samples are also taken at almost 2000 sites. Groundwater levels in the lower regions of the catchment need to be monitored in conjunction with streamflow. This can then yield important information on the groundwater contribution to river baseflow or recharge of aquifers from surface water systems. Precipitation Precipitation (snow and rainfall) is the principle input of sustainably available (renewable) water in a catchment. Rainfall is by far the dominant factor in South Africa, but on high ground, snow may also be an important source of precipitation. Monitoring throughout the catchment is essential, but the density of rain gauges should change according to the terrain and variability of rainfall. High lying ground should have a denser network of rain gauges than the outlet to the water management area. This tends often not to be the case in South Africa because of the difficulty of access to the monitoring site. Orthographic effects on rainfall quantity are strong in South Africa, and variability in rainfall is also strongly influenced by sharp changes in altitude. Rain-shadows, a result of the interaction of high relief with the prevailing winds, also cause significant changes in rainfall quantity at similar altitudes. Rain gauges need not be monitored on more than a daily basis. Where snow could be a significant component of precipitation, special snow gauges should be installed. Information such as short and medium term weather forecasts, 24 hour rainfall, meteosat images, radar images and synoptic maps are available from the South African Weather Service. Rainfall is the most important source of natural groundwater recharge and groundwater level measurements in the upper reaches of the catchment should be coordinated with measurements of rainfall volumes where the monitoring focus is on recharge. DWAF Head Office has started to include rainfall monitoring in conjunction with groundwater level monitoring at quite a few sites around the country. These data resides in Hydrological Information. Rainfall samples are also used for micro-chemistry analysis and isotopic signature analysis. Evaporation and Evapotranspiration Between 50 and 90% of rainfall evaporates back to the atmosphere in South Africa. This takes place through evaporation from open water bodies, as well as through interception and transpiration from vegetation. In the case of phreatophyte vegetation, water is transpired directly from the water table. There are various ways of monitoring the demand for water by the atmosphere. For reservoirs and lakes, the quantity is usually estimated using pan evaporation (the Symon s tank), and for agricultural crops, the American Class-A pan is used (the WMO standard). An evaporation pan or tank should therefore be placed near every significant reservoir or lake in each water management area. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 143

151 INTEGRATION OF GROUNDWATER MONITORING WITH OTHER MONITORING NETWORKS Farm dams need not be monitored, but the rate of evaporative water losses from these should be related to other meteorological data, such as temperature and saturation vapour deficit. Above vegetated areas, the situation is more complex. When the soil is saturated (between field capacity and porosity), vegetation can supply water at potential rate (i.e. atmospheric demand) and excess water can percolate to groundwater. When the soil is at less than saturation point (between field capacity and wilting point) transpiration takes place at less than potential rate, water is lost to the atmosphere but does not percolate to groundwater. For groundwater budgeting purposes, therefore, it is important to monitor those other variables which will enable one to calculate how much evapotranspiration is taking place. Calculations of evapotranspiration require measurements of solar radiation (solarimeter), vapour pressure deficit (wet and dry bulb thermometers or hygrometers) and windspeed. Much of the modern instrumentation is automated and can be located on a single automatic weather station. The density of monitoring stations required is approximately one every 500 km 2, but this is a subjective estimate. Figure 19 is a map showing the distribution of stations where evapotranspiration data are available for South Africa. FIGURE 19. MAP SHOWING NATIONAL DISTRIBUTION OF REFERENCE EVAPOTRANSPIRATION DATA STATIONS USED IN THE SAPWAT MODEL (FROM DWAF, 2000 DEVELOPMENT OF IRRIGATION WATER MANAGEMENT PLANS) Runoff The remainder of rainfall minus recharge to groundwater, evaporation and transpiration, in the long run, is runoff. This contains a mixture of baseflow (often groundwater-fed) and storm and quick flow. Runoff is monitored at weirs. Their locations depend on the importance of water in that catchment. GUIDELINES FOR GROUNDWATER RESOURCES MANAGEMENT MARCH 2004 PAGE 144