CONTENTS 1.1 BACKGROUND PURPOSE OF THIS REPORT REPORT STRUCTURE 2 2. THE HEX RIVER: GENERAL OVERVIEW 3

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2 CONTENTS 1. INTRODUCTION BACKGROUND PURPOSE OF THIS REPORT REPORT STRUCTURE 2 2. THE HEX RIVER: GENERAL OVERVIEW GENERAL LOCATION CLIMATE LAND AND WATER USE 4 3. THE MANAGEMENT PLAN WATER QUALITY Current status Water Quality Management objectives Water Quality Monitoring programme MACROINVERTEBRATES Current status Macroinvertebrates management objectives Invertebrates monitoring programme FISH Current status Fish management objectives Fish monitoring programme RIPARIAN VEGETATION Current status Riparian vegetation management objectives Riparian vegetation monitoring programme HABITAT Current status Habitat management objectives Habitat monitoring programme FREQUENCY AND LOCATION OF MONITORING IMPLEMENTATION REFERENCES CITED 18 pg 1

3 ANNEXURES ANNEX 1. Percentage values attributed to water quality parameters for calculation of the water quality index (WQI) 19 ANNEX 2. The SASS Version 5 scoring sheet 21 ANNEX 3. Fish Assemblage Integrity Index (FAII) 23 ANNEX 4. ANNEX 5. Parameters used to build the riparian (RVI) and habitat (IHI) integrity indices and their respective weights in the River Health Programme of South Africa 25 Habitat integrity assessment categories according to physical drivers and likely habitat responses for both riparian (RVI) and habitat (IHI) indices 26 pg 2

4 EXECUTIVE SUMMARY Terence to add. pg 1

5 1. INTRODUCTION 1.1 BACKGROUND The Hex River is situated in the North West Province of South Africa within the municipal area of Rustenburg. Currently there are numerous gold and platinum mines which discharge affluent into Hex River. The management of the Anglo American mine situated adjacent the Hex River is concerned that the river is in a degraded state and that this is largely caused by pollution. It considers the current state of the River as a threat to potential investment and lack of development opportunities in the area. Because of these concerns, the Mine Management has commissioned this study in order to assess the level of degradation and in the end produce a River Management Plan for key environmental indicators. 1.2 PURPOSE OF THIS REPORT The objective of the study, as outlined in the request to JAYMAT by the Mine Management is to help define a set of practical intervention strategies which will help in the Management of the River. This will be referred to as the Hex River Management Plan. Accordingly, were have reviewed the following key indicators of river health: Water Quality; Microinvertabrates Fish Ripirian vegetation Habitat These five indicators are generally considered to be sufficient indicators of River Health, and as such are normally used to proposed management guidelines. 1.3 REPORT STRUCTURE This report is divided into the following sections: Section 1 is the introduction; Section 2 is the general overview Section 4 is the Hex River Management Plan Section 5 is the summary of the Hex River Management Plan and Section 6 is the conclusions. pg 2

6 2. THE HEX RIVER: GENERAL OVERVIEW 2.1 GENERAL 2.2 LOCATION The Hex River is the largest river system Rustenburg area in terms of volume of runoff. It is a source of water supply for many in the region. It has been impounded upstream by the Bospoort Dam and downstream by the Vaalkops Dam. There are thus important opportunities for development, as well as for ensuring adequate conservation of this important river system. This chapter provides a short overview of the existing socio-economic and biophysical conditions prevailing in the catchment and the estuary, and is intended as background and context for the management plan and trends that follow. The Hex River is situated in the mining town of Rustenburg, in the North West Province of South Africa. Figure 1: Hex River flowing into the Bospoort dam pg 3

7 2.3 CLIMATE The Hex River falls within the Summer Rainfall Climatic Zone. The area is characteristically warm to hot with rainfall that is erratic and extremely variable, ranging from 450 to 750 mm per year. Temperatures vary between extremes of 6.0 C and 40 C with an average of 19 C. The winter weather is dominated by perturbations in the westerly circulation as a result of the succession of cold fronts moving over the region. The passage of a cold front is characterised by pronounced variations in wind direction, wind speed, temperature, humidity and surface pressure. Airflow ahead of the cold front has a distinct north-northwesterly to northeasterly component. Following the cold front, the northerly wind is replaced by winds with a distinct southerly component. 2.4 LAND AND WATER USE To the east and north of the study area occur a number of mines that extract platinum, chrome and granite reserves. The eastern portion of the study area also includes large portions of agricultural land that are cultivated for maize, tobacco, sunflower and citrus produce. The land is also increasingly be used for both formal and informal residence. There is also a significant ecotourism use of the area. pg 4

8 3. THE MANAGEMENT PLAN Implementing the monitoring programme and management plan to support the Hex River involves several elements, including: i) establishing monitoring objectives, ii) defining data needs, iii) developing a sampling protocol, iv) data collection and handling, and v) data management. The purpose of the Management Plan is to provide an indication of the deviation of the habitat (downstream the mining discharge) from the reference conditions (upstream). In the long-term, the goal is to determine, from the community level data, whether there are shifts through time and space in the Hex River. 3.1 WATER QUALITY Current status Among the various issues of public concern for the Hex River, water quality is mentioned most frequently. This is true among the river users, river landowners, and interested citizens. Local citizens want to be able to swim and eat its fish without any health hazards, and they want to see the river without floating litter drifting back and forth with the tide. The long-term water quality trends carried out by du Plessis (2008) showed a significant mine water, industrial effluent and sewage impact on the Hex River after the confluence with the tributaries. Inferior water quality conditions including contributions to the salt (TDS, CI, SO4) as well as nutrient and metal concentrations is evident from the Dorp Spruit draining the Rustenburg Northern Industrial Zone (Barnard, 1999). The assessment of the current water quality situation indicated non-compliance towards the Target Water Quality Guideline Ranges (TWQGR) as stipulated by the Department of Water Affairs and Forestry (DWAF, 1996), rendering the water unfit for domestic use, irrigation and livestock watering. The sources feeding the tributaries contain water of inferior quality with a direct associated environmental risk. However, at present the risk potential is contained in the system but in case of a specific environmental event, such as high rainfall over a short period of time, could be released with a significant environmental impact and decrease in aquatic diversity (e.g. fish). In 2005, the National River Health Programme (RHP) of the CSIR concluded that the Hex River and its tributaries were (in terms of water quality) in an unsustainable state (Box 1) owing to various water discharges into the river. Further, the programme called on DWAF to institute rehabilitative and mitigatory measures that could help reverse the situation. pg 5

9 BOX 1 The water quality of the area has been described as POOR, as the water does not comply with the TWQGR for domestic use as well as irrigation Water Quality Management objectives MAIN PARAMETERS Dissolved Oxygen FREQUENCY OF SAMPLING 2 3 times per year ph Total dissolved salts (TDS) Temperature The current water quality programme priority is to maintain and operate an effective and uniform monitoring system for measuring and monitoring the quality of the Hex River water. Thus, for objectives it is advised that the management of the River should work towards achieving the Water Quality Guidelines as published by DWAF (2006). These objectives are listed in Table 1. Table 1: Water quality management objectives for Hex River. These are derived from DWAF (2006). Variables Guidelines (DWAF 2006) Dissolved Oxygen (mg l -1 ) The median guideline for DO for the protection of aquatic biota is >5mg l -1. Ph The ph value should not be allowed to vary from a ph range of 6.5 to 8.5 Total Dissolved Salts (mg l -1 ) TDS concentrations of less than 450 mg l -1 can be described as non-saline, 450 to 1000 mg l -1 as saline and 1000 to 2400 mg l -1 as very saline. Concentrations greater than 3600 mg l-1 are considered extremely saline Temperature ( o C) Water temperature should not be allowed to vary from the ecosystems background average daily temperature (considered to be normal for that specific site and time of day) by > 2 C, or by > 10%, whichever estimate is the more conservative. The temperatures of inland waters in South Africa generally range from 5-30 C (DWAF, 1996). NB: The DWAF guidelines should be used as water quality objectives (what is to be achieved). pg 6

10 3.1.3 Water Quality Monitoring programme Four key parameters (TDS, ph, dissolved oxygen and temperature) from the Water Quality Index (WQI) should be measured in the field with lightweight compact field instruments and according to Standard Methods (1995). Further to monitoring the four variables, it is very important to understand the role that each plays in the aquatic ecosystem and this would need to be explained when writing the monitoring report. In general terms the roles of the variables to quantify are: 1. Dissolved Oxygen: measure the amount of gaseous oxygen (O2) dissolved in the river. The maintenance of adequate dissolved oxygen (DO) is critical for the survival and functioning of the aquatic biota as it is required for the respiration of all aerobic organisms 2. ph: the ph of natural waters is determined by both geological and atmospheric influences, as well as by biological activities 3. Total Dissolved Salts: most macroinvertebrate taxa are sensitive to salinity, with toxic effects likely to occur in sensitive species 4. Temperature: water temperature plays an important role in aquatic ecosystems by affecting the rates of chemical reactions and therefore the metabolic rates of organisms The water quality is important to assist in the interpretation of biological results because of the direct influence water quality has on aquatic life forms. The data can also be used to establish baseline conditions, define trends, and assist with the development of a water quality model of the Hex River system (see Annex 1 for more information on other parameters used to calculate WQI). Table 2 presents the Water Quality Monitoring programme for the Hex River. Table 2 Water Quality Monitoring programme. WATER QUALITY ISSUES REQUIRED INDEX FOR ANALYSIS DELIVERABLE FINAL RESPONSIBILITY PROGRAMME ACTION DWAF Water Quality Index (WQI) Report - analysis of data from main stem and tributary gauges to present a description of the hydrology of the river, including its variability. DWAF (Water Act 36 of 1998). Mine could initiate in absence of DWAF. pg 7

11 3.2 MACROINVERTEBRATES Current status Macroinvertebrates eat on algae and leaves from the river, and in turn are food for larger animals such as fish which are a source of food for birds and humans. Macroinvertebrate communities respond relatively quickly to localised conditions in a river, including water quality and habitat diversity (Box 2). They are common, have a wide range of sensitivities and have suitable life-cycle duration that could indicate short- to medium-term impact on water quality. BOX 2 The cumulative impacts of reduced water quality flow and habitat modification have had a large effect on macroinvertebrate diversity, thus the current status has been described as POOR (du Plessis, 2008) Macroinvertebrates management objectives KEY PARAMETER Invertebrates instream FREQUENCY OF SAMPLING 2 3 times per year Macroinvertebrate species exhibit a wide variation of response to pollutants. Seasonal samples of the macroinvertebrate community can indicate the effects of pollutant sources which may not have been detected by either intermittent physic-chemical sampling or continuous monitoring of a restricted range of parameters. Good water quality should support organisms from all three categories presented in Table 3. Table 3 Category of invertebrates with their given level of pollution tolerance SENSITIVE to pollution SOMEWHAT pollution tolerant TOLERANT to pollution Mayfly larvae Alderfly larvae Midge fly larvae Stonefly larvae Crane fly larvae Black fly larvae Caddisfly larvae Fishfly larvae Chironomid larvae Dobsonfly Watersnipe fly larvae Aquatic worms Beetle Damselfly fly larvae Lung snails Flatworm Dragonfly larvae Leeches Gilled snails Beetle larvae Clam or Mussel Crayfish Scuds Sowbug pg 8

12 3.2.3 Invertebrates monitoring programme Macroinvertebrates are good indicators of the conditions in a river, especially in the short-term. The South African Scoring System version 5 (SASS5) is an index of aquatic macroinvertebrates for biomonitoring (Dickens and Graham, 2002). The method to follow uses a sweep net over a defined distance with a standardized number of sweeps. This sampling involves the identification of organisms (without any estimate of abundance) and assigns a score determined by organic pollution tolerance. Monitoring should not be carried out when the river is in flood, because the collection will not be a true representation of the biota of the site. In the field, the procedure involves collecting invertebrates from the watercourse using a standard net (soft 1 mm mesh net on a 30 cm square frame on a stout handle) over a wide area to ensure that the full variability of habitat is sampled (see Table 5 for more details), including: 1. Stones in current (free or loose stones), bedrock or any solid object in current 2. Stones out of current (moveable stones), bedrock or any solid object out of current PROCEDURE: kick the stones or rub with the hands or boots for approximately two minutes. Place the net downstream of the stones in a position where the current will carry the dislodged biota into the net. 3. Marginal vegetation hanging into or growing at the edge of the stream PROCEDURE: the net is pushed vigorously into a segment with different kinds of vegetation (total length of two metres). 4. Aquatic vegetation not confined to the river banks, including filamentous algae and the roots of floating aquatics PROCEDURE: push the net repeatedly against and through the vegetation under the water over and area of approximately one square metre. 5. Gravel, sand and mud habitats where available Once collection is complete, each of the samples should be washed down to the bottom of the net until the water runs clean, then carefully tipped into separate trays by inverting the net. Discarded vegetation/debris material was retained on a parallel sorting tray to collect invertebrates that might be hiding. Organisms as listed on the SASS5 scoring sheet (Annex 2) are identified to family level. Samples can be identified to family in the field using Gerber and Gabriel (2002). Each taxon has been assigned a quality score, based on its susceptibility or resistance to pollution and perturbations (Dickens and Graham, 2002). The lowest scores are assigned to the taxa that are resistant and the highest score to those susceptible to pollution, such as those listed on Table 3. Viewing and identification is done for a maximum of 15 minutes. Upon completion, the sample is either returned to the river or preserved for returning to a laboratory. pg 9

13 The results are all semi-quantitative and the quality of data depends to a large extent on the persons doing the sampling; that they do it in exactly the same way all the time otherwise comparisons will be jeopardized. 3.3 FISH Current status Fish comprise one of the main biological components of aquatic ecosystems. Because they are relatively long-lived and mobile they can indicate long-term influences on general habitat conditions in a river reach. They represent a variety of trophic levels and hence integrate effects of environmental changes. Fish Assemblage Integrity Index (FAII) is an expression of the degree to which a fish population differ from its expected undisturbed condition. Currently, fish species are under stress conditions (Box 3) due to the deterioration of the water quality originated from the mining activities. BOX 3 The current Fish Assemblage Integrity is POOR as a consequence of the loss of sensitive species to flow modifications and obstructions (du Plessis, 2008) Fish management objectives MAIN PARAMETER Native fish FREQUENCY OF SAMPLING every 3 years The principal objective is to protect the fish diversity in the Hex River by determining the amount of degradation of fish habitat associated with the industrial effluent, determine population trends in fish populations and to determine losses to the fishery. Ultimately, achieving these objectives will give an indication of whether fish populations are declining, increasing or stable and whether fish habitat in the river has been degraded as a result of mining activities Fish monitoring programme Fish are good indicators of long-term influences on the habitat of a river. A Fish Assemblage Integrity Index (FAII), based on biological river segments has been developed (Kleynhans, 1999). The FAII was developed for application in the assessment required for the RHP. The pg 10

14 FAII considers the relative intolerance on indigenous fish expected to occur, frequency of occurrence and percentage of fish with externally evident disease or anomalies. Four habitats must be included, according to flow-depth classes as follows: 1. Slow (<0.3 m/s), shallow (<0.5 m), including shallow pools and backwaters. 2. Slow (<0.3 m/s), deep (>0.5 m), including deep pools and backwater 3. Fast (>0.3 m/s), shallow (<0.3 m), including shallow runs, rapids and riffles 4. Fast (>0.3 m/s), deep (0.3 m), including deep runs, rapids and riffles PROCEDURE: Capture results are recorded as number of fish caught during each effort with a net, or the number of fish caught per time unit (minutes) with an electroshocker. The expected FAII rating for a fish habitat segment is calculated according to Kleynhans (1999) and results can be compared with historical data (du Plessis, 2008) and with the aid of expert knowledge. For more details on how to interpret the results, see Annex RIPARIAN VEGETATION Current status Riparian vegetation regulates river flow, improves water quality, provides habitats for faunal species and corridors for their movement, controls river temperatures, provides nutrients and maintains bank stability. According to DWAF (1999), changes in riparian vegetation structure or function are commonly associated with changes in river flow, exploitation for fire wood or changing use of the riparian zone (for example for grazing or ploughing). Box 4 summarises the current status of the Riparian Vegetation of the Hex River. BOX 4 The Riparian Vegetation Integrity has recently been described as GOOD, indicating that the ecosystem is in a good state and biodiversity is largely intact (du Plessis, 2008). pg 11

15 3.4.2 Riparian vegetation management objectives MAIN PARAMETERS Vegetation decrease FREQUENCY OF SAMPLING Every 3 years Exotic vegetation Bank erosion Water abstraction Flow modification The region is characterised by nine vegetation types belonging to the clay, Kalahari, Kimberley, mixed bushveld and highveld grassland categories (Table 4) (van Rooyen & Bredenkamp, 1996). Table 4. Natural vegetation of the area Woody species Dichrostachys cinereus Grewia flava Ziziphus mucronata, Grasses Bothriochloa Ischaemum afrum Panicum coloratum Sehima galpinii Setaria increassate Healthy riparian zones maintain channel form and serve as important filters for light, nutrients and sediment. Thus, water quality problems must also be addressed through public awareness efforts and by encouraging good land use in riparian areas Riparian vegetation monitoring programme Riparian zones needs to be maintain in healthy conditions as these zones can represent as important filters for light, nutrients and sediments. A combination of remotely sensed data and field survey can be used. Data collected should include river channel, riparian zone (including invasion), ground and vegetation cover, main species present and disturbances, using the Riparian Vegetation Index (RVI). The RVI is a site-specific approach which places particular emphasis on the ecological integrity of the riparian vegetation. pg 12

16 This assessment is based on three main groups: 1. Hydrological modification: seasonality of floods (low or no flows to large and moderate floods 2. Bank structure modification: marginal and non-marginal (substrate exposure, invasive vegetation, erosion and channel straightening) 3. Riparian zone connectivity: fragmentation in the riparian zone (lateral and longitudinal) Weights have been assigned to each parameter (Annex 4) based on the literature (Kleynhans, 1996). Each parameter is assessed through field observations. Following the field observations and assessments, a score (maximum value = 25) is assigned for each parameter, and the impact of the parameter on habitat integrity is calculated as specified. For reporting purposes, scores of RVI were categorised by the RHP into the following bands: A= (100); B = (80-99); C = (60-79); D = (40-59); E = (20-39); F = (0-19), (Kleynhans, 1996). Category A represents a natural unmodified river system, while category F represents a very highly modified system with almost a complete loss of natural habitat (Annex 5). 3.5 HABITAT Current status Habitat availability and diversity determine aquatic community structure, therefore, habitat degradation could ultimately affect biological communities. Channel modifications (Box 5) have been caused by the mining diversions that impact on the riparian zone. BOX 5 According to du Plessis (2008) the habitat integrity was described as FAIR, indicating that sensitive species may be lost, with tolerant or opportunistic species dominating Habitat management objectives MAIN PARAMETERS Exotic macrophytes FREQUENCY OF SAMPLING 5 years Exotic fauna Channel modification Inundation Flow modification pg 13

17 The ultimate objective of the assessment of habitat integrity is to monitor habitat conditions using regulatory avenues to reduce impacts from development projects that should also help to identify problems and minimize impacts on the stream resource Habitat monitoring programme Habitat availability and diversity are major determinants of aquatic community structure. The Index of Habitat Integrity (IHI) can be used to evaluate the impact of major disturbance factors on the capacity of the river to provide suitable living conditions for organisms. As with the RVI, weights have been assigned to each parameter (Annex 4) based on the literature (Kleynhans, 1996). Each parameter is assessed through field observations. Following the field observations and assessments, a score (maximum value = 25) is assigned for each parameter, and the impact of the parameter on habitat integrity is calculated as specified. This assessment is based on five main groups: 1. Hydrological modifications: seasonality of floods (low or no flows to large and moderate floods 2. Physico-chemical modification: including the parameters measured for water quality 3. Bed modification: cover provided by the substrate (sedimentation and algal growth) 4. Bank modification: change in cover (vegetation and abiotic) for biota (both marginal and non-marginal characteristics) 5. Connectivity modification: changes that influence movement of instream biota (longitudinal and lateral) The result of the integrity assessment is a percentage that is used to derive a descriptive habitat integrity assessment for the instream and riparian zone components (Annex 5). For reporting purposes, scores of habitat integrity were categorised by the RHP into the following bands: A= (100); B = (80-99); C = (60-79); D = (40-59); E = (20-39); F = (0-19), (Kleynhans, 1996). Category A represents a natural unmodified river system, while category F represents a very highly modified system with almost a complete loss of natural habitat. 3.6 FREQUENCY AND LOCATION OF MONITORING Site selection should consider the following: Habitat present at the site should be representative Preferably, sites should not be close to artificial structures such as bridges and weirs Factors such as safety and accessibility are very important pg 14

18 Table 5. Typical spatial scale for monitoring the main indices Index Component Spatial Scale WQI Water SASS5 Macroinvertebrates Up to 20 m FAII Fish Homogeneous segments, typically kms RVI Riparian Vegetation 10s of metres IHI Habitat 5 km Table 6. Frequency of monitoring for various biomonitoring indices Index Component Frequency Comment WQI Water 2-3 times per year Preferably during dry season, at end of dry season and at end of wet season SASS5 Macroinvertebrates 2-3 times per year Preferably during dry season, at end of dry season and at end of wet season FAII Fish every 3 years RVI Riparian Vegetation every 3 years To coincide with fish monitoring IHI Habitat every 3-5 years Factors affecting monitoring The environmental monitoring programme must continue through time as prescribed by the objectives and management plan. However, there can be two main factors to consider that may affect monitoring frequencies, namely: Major pollution spills, that if occurred, the monitoring should be conducted as soon as possible and doubling the frequency for the first year after the disturbance Major floods can also wash away habitat and invertebrates and monitoring should be carried out 1 to 2 months after the disturbance pg 15

19 4. IMPLEMENTATION The plan serves as a guide for promoting good stewardship of the Hex River. The challenge now is to put the plan into action and produce tangible results. Through implementation, the local community can take steps to achieve cleaner water in the river, and better habitat for many species and thus enhancing the natural views, and exemplary development designs that conserve the open spaces and natural/ cultural character of the Hex River System. This monitoring of the indicators is primarily a tool for keeping a finger on the pulse of long-term environmental trends such as the gradual deterioration in water quality and ecological integrity and the possible causes or sources of these. Hence, where this has been shown to occur, the management plan can contribute to a number of management action which addresses these issues. The formulation and implementation of this management plan should involve all the stakeholders and interested and affected parties in an integrated manner, with clear roles and responsibilities assigned to each. The Anglo mine should advocate this plan to the broader community and take actions to implement specific recommendations. Not all the recommendations can be implemented at once. Some recommendations will require a short-term effort, while others will be ongoing and never ending, and still others will require much time and effort organizing and building partnerships and funding to be achieved. People and organizations such as landowners, river users, community interest groups, developers, or governmental entities that simply decide that this plan presents an appropriate way to manage the river can implement many of the recommendations. The report is specifically designed to assist environmental decision makers of the mine with the management plan of Hex River System. Hence the results obtained through data collection, analysis of results and interpretation and reporting on environmental trends should lead to management actions where these are required. Such management actions can only realistically arise following the reporting on the indicators (water quality, fish, microinvertebrates, riparian vegetation and habitat). The management process to be followed in the implementation is illustrated in Figure 2: pg 16

20 Figure 2. Management process to be followed in the implementation pg 17

21 5. REFERENCES CITED Department of Water Affairs and Forestry (1999). National Aquatic Ecosystem Biomonitoring Programme: National Implementation Assessment. NAEBP Report Series No 8. Dickens, C. & Graham, P. (2002). The South African Scoring System (SASS) version 5: Rapid Bioassessment method for rivers. African Journal of Aquatic Science, 27: 1-10 du Plessis, J. (2008) The assessment of the water quality of the Hex River catchment North West Province, MSc Thesis, University of Johannesburg. Gerber A & Gabriel MJM (2002) Aquatic invertebrates of South African rivers: field guide. WQS, DWAF, Private Bag X313, Pretoria Kemper, N. (2001). RVI Riparian Vegetation Index. WRC Report No 850/3/01 Kleyhans, C. (1999). The development of a fish index to assess the biological integrity of South African rivers. Water SA, 25: National River Health Programme. A programme sponsored by the Departments of Water Affairs and Forestry, Environmental Affairs and Tourism, and the Water Research Commission, Pretoria, South Africa. URL: Standard methods (1995). Standard methods for the examination of water and wastewater. American Public Health Association, 953pp van Rooyen, N. & Bredenkamp, G. (1996) Vegetation of South Africa, Lesotho and Swaziland, Department of Environmental Affairs & Tourism, Pretoria. pg 18

22 ANNEX 1. Percentage values attributed to water quality parameters for calculation of the water quality index (WQI) Parameter ph Dissolved solids (mg l -1 ) DBO (mg l -1 ) DO (mg l -1 ) Temp ºC Total coliforms (nº/100ml) Colour (hansen) Turbidity (NTU) Conductivity Hardness (mg l -1 ) μmhos cm -1 CaCO 3 Detergent s (mg l -1 ) Weight % Analytical 1 >20000 >15 0 >50/>-8 >14000 >250 >400 >16000 >1500 > value of the / parameter / / / / / / / / Parameter 7 <100 < /16 <50 <3 >0.5 <750 > Magnesium Nitrates Sulphates Ammonia Chloride Cyanides Pesticides Nitrites (mg l -1 ) Oil and grease Apparent % value (mg l -1 ) (mg l -1 ) (mg l -1 ) nitrogen (mg l -1 ) (mg l -1 ) (mg l -1 ) (mg l -1 ) aspect C i Sodium (mg l -1 ) (mg l -1 ) (quality) Weight % Analytical >500 >500 >100 >1500 >1.25 >1500 >1 >2 >1 >3 worst 0 value of the very bad 10 parameter bad unpleasant inappropria 40 te normal acceptable pleasant good very good 90 <10 < excellent 100 % value C i pg 19

23 The WQI is then calculated as follow: Where: Ci = percentage value corresponding to the parameter Pi = parameter weight K = constant of adjustment in function of the visual aspect of the water, as follows: 1.00 for clear water; 0.75 for water with slightly unnatural colour and turbidity; 0.50 for polluted appearance water with odour; 0.25 for dark water that presents fermentation and strong odour. pg 20

24 ANNEX 2. The SASS Version 5 scoring sheet SASS version 5 Score Sheet Date: Collector: Grid reference: S:, E:, Site code: River: Site description: Weather condition: Temp: C DO: mg l -1 ph: Cond: ms m -1 Taxon S Veg GSM TOT Taxon S Veg GSM TOT Taxon S Veg GSM TOT PORIFERA 5 HEMIPTERA 3 DIPTERA Athericidae Belostomatidae COELENTERATA 1 Corixidae 3 Blepharoceridae TURBELLARIA 3 Gerridae 5 Ceratopogonidae ANNELIDA 1 Hydrometridae 6 Chironomidae Oligochaeta Leeches 3 Naucoridae 7 Culicidae CRUSTACEA 13 Nepidae 3 Dixidae Amphipoda Potamonautidae 3 Notonectidae 3 Empididae Atyidae 8 Pleidae 4 Ephydridae Palaemonidae 10 Veliidae/M veliidae 5 Muscidae HYDRACARINA 8 MEGALOPTERA 8 Psychodidae Corydalidae PLECOPTERA 14 Sialidae 6 Simulidae Notonemouridae Perlidae 12 TRICHOPTERA 10 Syrphidae Dipseudopsidae EPHEMEROPTERA 4 Ecnomidae 8 Tabanidae Baetidae 1 sp Baetidae 2 sp 6 Hydropsychidae 1 sp 4 Tipulidae Baetidae >2 sp 12 Hydropsychidae 2 sp 6 GASTROPODA Ancylidae Caenidae 6 Hydropsychidae > 2 sp 12 Bulinidae pg 21

25 Biotopes sampled: Ephemeridae 15 Philopotamidae 10 Hydrobiidae SIC: Time: min Heptageniidae 13 Polycentropodidae 12 Lymnaeidae SOOC: Time: min Leptophlebiidae 9 Psychomyiidae/Xiphocen 8 Physidae Average size of stones: Oligoneuridae 15 Cased caddis: Planorbinae cm Polymitarcyidae 10 Barbarochthonidae SWC 13 Thlaridae Bedrock: Aquatic veg: Dom sp: Prosopistomatidae 15 Calamoceratidae ST 11 Viviparidae ST Mveg IC: Dom sp: Mveg OOC: Dom sp: Gravel: Sand: Mud: Hand picking/visual obs: Flow: Low/Medium/High/Flood Turbidity: Low/Medium/High Riparian land use: Disturbance in the river: e.g. cattle drinking point, floods Observations: e.g. smell & colour Teloganodidae SWC 12 Glossosomatidae SWC 11 PELECYPODA Corbiculidae Tricorythidae 9 Hydroptilidae 6 Sphaeriidae ODONATA 10 Hydrosalpingidae SWC 15 Unionidae Calopterygidae ST,T Chlorocyphidae 10 Lepidostomatidae 10 SASS Score Chlorolestidae 8 Leptoceridae 6 No. of Taxa Coenagrionidae 4 Petrothrincidae SWC 11 ASPT Lestidae 8 Pisuliidae 10 Platycnemidae 10 Sericostomatidae SWC 13 Sample collection effort exceeds method? Protoneuridae 8 COLEOPTERA 5 Dytiscidae Aeshnidae 8 Elmidae/Dryopidae 8 Other biota including juveniles: Corduliidae 8 Gyrinidae 5 Gomphidae 6 Haliplidae 5 Libellulidae 4 Helodidae 12 LEPIDOPTERA 12 Hydraenidae 8 Comments: Pyralidae Hydrophilidae 5 Limnichidae 10 Psephenidae 10 Procedure: Kick SIC & bedrock for 2 mins, max. 5 mins; Kick SOOC & bedrock for 1 min; Sweep marginal vegetation (IC & OOC) for 2m total and aquatic veg 1m 2 ; Stir & sweep gravel, sand, mud for 1 min total; * = airbreathers; Hand picking & visual observation for 1 min. record in biotope where found; Score for 15 mins/biotope but stop if no new taxa seen after 5 mins; Estimate abundances: 1 = 1, A = 2.10, B = , C = , D = >1 000; S = Stone, rock & solid objects; Veg = All vegetation; GSM = Gravel, sand, mud; SWC = South Western Cape; T = Tropical; ST = Sub-tropical; Rate each biotope sampled: 1 = very poor (i.e. limited diversity), 5 = highly suitable (i.e. wide diversity) pg 22

26 ANNEX 3. Fish Assemblage Integrity Index (FAII) FAII ASSESSMENT CLASSES Class rating Description of generally expected conditions for integrity classes Relative FAII score (% of expected) A Unmodified, or approximate natural conditions closely. B Largely natural with few modifications. A change in community characteristics may have taken place but species richness and presence of intolerant 80 to 89 species indicate little modification. C Moderately modified. A lower than expected species richness and presence of most intolerant species. Some impairment of health may be evident at 60 to 79 the lower limit of this class. D Largely modified. A clearly lower than expected species richness and absence or much lowered presence of intolerant and moderately intolerant 40 to 59 species. Impairment of health may become more evident at the lower limit of this class. E Seriously modified. A strikingly lower than expected species richness and general absence of intolerant and moderately intolerant species. Impairment 20 to 39 of health may become very evident. F Critically modified. An extremely lowered species richness and an absence of intolerant and moderately intolerant species. Only tolerant species may be present with a complete loss of species at the lower limit of the class. Impairment of health generally very evident. 0 to 19 pg 23

27 FAII value (exp) = Σ IT x ((F + H)/2) where: Exp = Expected for a fish habitat segment IT = Intolerance rating for individual species expected to be present in a fish habitat segment and in habitats that were sampled F = Expected frequency of occurrence rating for individual species expected to be present in a fish habitat segment and at sites that were sampled H = Expected health rating for species expected to be present. The observed situation is represented by: FAII value (obs) = Σ IT x ((F + H)/2) where: Obs = Observed for a fish habitat segment The relative FAII score is calculated by: Relative FAII score = FAII value (obs)/ FAII value (exp) x 100 pg 24

28 ANNEX 4. Parameters used to build the riparian (RVI) and habitat (IHI) integrity indices and their respective weights in the River Health Programme of South Africa Parameter RVI Weights IHI Weights Fish Assemblage N/A Exotic Macrophytes N/A 9 Exotic fauna N/A 8 Vegetation decrease 13 N/A Exotic vegetation 12 N/A Bank erosion 14 N/A Channel modification Water abstraction Inundation Flow modification Water quality Bed modification N/A 13 Solid Waste N/A 6 Impact of parameter on habitat integrity The impact of all the individual parameters are summed up and expressed as a percentage and subtracted from 100 to arrive at an independent value of both riparian and habitat integrity. pg 25

29 ANNEX 5. Habitat integrity assessment categories according to physical drivers and likely habitat responses for both riparian (RVI) and habitat (IHI) indices HABITAT INTEGRITY CATEGORY A B C DESCRIPTION Unmodified, natural reference condition: All physical drivers unmodified or virtually unmodified. If use of the resource is present, the impact of such use falls completely within the natural disturbance regimes both in terms of extent and severity. Largely natural with few modifications: A small change in natural habitats may have taken place but the ecosystem functions are essentially unchanged. Physical drivers: Hydrology: The flow regime has only slightly been modified Geomorphic: limited to slight sediment changes Physico-chemical changes: Water clarity may sporadically be slightly influenced. At worst, only sporadic traces of toxics present. Salts may sporadically be slightly increased. Associated habitat conditions: Instream: Very little change in habitat types and their dimensions and frequency. Connectivity between habitats virtually unchanged. Riparian: Riparian habitat close to natural in terms of biophysical characteristics. Very little modification and use of riparian zone. Virtually no fragmentation. Moderately modified: Loss and change of natural habitat and biota have occurred, but the basic ecosystem functions are still predominantly unchanged. Physical drivers: Hydrology: The flow regime may have been significantly modified and direct manipulation by impoundments may be present. Geomorphic: sediment changes due to increased inputs or flow may have increased significantly. Physico-chemical changes: changes in nutrients, salts, oxygen concentration and temperature may deviate significantly from the reference. Low levels of toxics may sporadically be present. Associated habitat conditions: Instream: Dimensions and frequency of some habitat types have changed significantly. Fragmentation of habitats may often be present Riparian: Changes in the structure of the zone may be common. Some fragmentation of the zone may often be present. RATING (% OF TOTAL) pg 26

30 HABITAT INTEGRITY CATEGORY D E F DESCRIPTION Largely modified. A large loss and change of natural habitat, biota and basic ecosystem functions has occurred. Physical drivers: Hydrology: The flow regime has been extensively modified and manipulation by impoundments may be present. Geomorphic: Drastic changes in sediment loads due to increased inputs or flow modification may have occurred. Physico-chemical changes: nutrients, salts, oxygen concentration and temperature may deviate considerably from the reference. Low levels of toxics may regularly be present. Associated habitat conditions: Instream: Dimensions and frequency of some habitat types may differ drastically from the reference. Fragmentation of habitats may often and extensively be present. Riparian: Extensive changes of the zone may be present. Significant fragmentation of the zone may have occurred. Seriously modified. The loss of natural habitat, biota and basic ecosystem functions is extensive. Physical drivers: Hydrology: The flow regime may have been extensively and severely modified and manipulation by impoundments is likely to be present. Geomorphic: Extensive and severe changes in sediment loads due to increased inputs or flow modification may have occurred. Physico-chemical changes: nutrients, salts, oxygen concentration and temperature may deviate severely and regularly from the reference. Significant levels of toxics may regularly be present. Associated habitat conditions: Instream: Dimensions and frequency of some habitat types may differ extensively and severely from the reference. Fragmentation of habitats may regularly and extensively be present Riparian: Severe and extensive changes of the zone may be present. Extensive fragmentation of the zone may have occurred. Critically / Extremely modified: Modifications have reached a critical level and the system has been modified completely with an almost complete loss of natural habitat and biota. In the worst instances the basic ecosystem functions have been destroyed and the changes are irreversible. Physical drivers: Hydrology: The flow regime may be extensively and extremely modified and manipulation by impoundments is often present. Geomorphic: Extensive and extreme changes in sediment loads due to increased inputs or flow modification may have occurred. Physico-chemical changes: Nutrients, salts, oxygen concentration and temperature may deviate extremely and very regularly from the reference. High levels of toxics may regularly be present. Associated habitat conditions: Instream: Dimensions and frequency of some habitat types may differ extensively and extremely from the reference. Fragmentation of habitats may be severe. Riparian: Extreme and extensive changes of the zone may be present. Fragmentation of the zone may be severe. RATING (% OF TOTAL) pg 27