GROUND WATER/SURFACE WATER INTERACTIONS 1-3 AWRA SUMMER SPECIALTY CONFERENCE 2002

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1 JULY GROUND WATER/SURFACE WATER INTERACTIONS 1-3 AWRA SUMMER SPECIALTY CONFERENCE bLg Pd6 IMPLEMENTING ADAPTIVE MANAGEMENT OF WATER RESOURCES IN THE ST. JOHNS RIVER WATER MANAGEMENT DISTRICT. William J. Dunn', Robert J. Epting*, David Stites3, and Hal Wilkening' ABSTRACT Water supply planning conducted by the St. Johns River Water Management District (SJRWMD) shows that there is a finite limit to the amount of groundwater withdrawal that can be sustained without causing adverse impacts to the water resource and dependent natural systems. Analyses identified caution areas in which future increases in groundwater withdrawals are projected to cause unacceptable adverse impacts to natural resources. Water supply plans have been developed for each caution area identifying a sustainable mix of sources to meet projected water use demands, while avoiding adverse impacts to natural resources. To be better prepared for managing water resources SJRWMD adopted an adaptive management approach for water supply management. A central tenet of AM is to monitor the resource of concern in order to test outcome hypotheses and make better-informed future management decisions. A regional water resource monitoring plan for the caution areas is being implemented as the first step in adaptively managing this finite resource. KEY TERMS: adaptive management, water resources, water supply planning. INTRODUCTION The mission of the St. Johns River Water Management District (SJRWMD) is to manage water resources to ensure their continued availability while maximizing both environmental and economic benefits. In April 2000, the SJRWMD adopted its District Water Supply Plan (DWSP). The DWSP is both a summary of the extensive water supply planning and assessment investigations conducted during the past decade by the St. Johns River Water Management District and a long range water supply plan. These investigations indicate that there is a finite limit to the amount of groundwater withdrawal that can be sustained. Under the SJRWMDs current water supply planning efforts, Water 2020, priority water resource caution areas (PWRCAs) have been identified (Figure 1). These are areas of the SJRWMD where year 2020 projected groundwater withdrawals may cause unacceptable adverse impacts to the water resource and dependent natural systems. Adaptive management (AM) is a process for managing natural resources that applies the best available information, recognizes uncertainty, and provides for structured learning through hypothesis testing and resource monitoring. Adaptive management accepts the fact that resource agencies must make management decisions based on incomplete information, or there is uncertainty about the effects of management decisions. It views management not only as a way t? achieve objectives, but also as a process for learning more about the resource or system being managed. The intent of this method is to incorporate the views and knowledge of all interested parties through an open collaborative process. In the adaptive management approach, structured learning occurs by testing management policies as though they were hypotheses. Thus, learning while doing is an inherent objective of adaptive management; and as resource managers learn they can adapt policies and planning to improve management success and be more responsive to future conditions. 'Senior Water Resources Scientist, CH2M HILL, 3011 SW Williston Road, Gainesville, FL Tel FAX Bdunn@ch2m.com. 'Senior Regulatory Scientist, Department of Resource Management, St. Johns River Water Management District, P.O. Box 1429, Palatka, FL 32178; %enior Scientist, CH2M HILL, Gainesville, FL; 'Director, Department of Resource Management, St. Johns River Water Management District, Palatka, FL. 247

2 Resource Caution area Figure 1. St. Johns River Water Management District and shaded Water Resource Caution Areas. SJRWMD ADAPTIVE MANAGEMENT PROCESS The application of adaptive management concepts to resource management is described in recent studies and summaries (e.g. Johnson, 2000; Gray, 2000; Lee, 1993; Nyberg 1999, Lee, 2000). Nyberg (1999) summarized AM as a six-step process that SJRWMD is using to guide its resource management plan (Table 1). SJRWMD has been managing the water resources of the St Johns River watershed for decades. Ongoing resource management includes activities in all six water resource caution areas. The current focus on AM is a refinement of their resource management program. 248

3 Table 1. SJRWMDs Six Step Adaptive Management Process Steps in Adaptive Management (Nyberg, 1999) '1--Assess Problem -Define scope of management problem -Define measurable management objectives -Identify key indicators for each objective -Explore effects of alternative actions on indicators -Make explicit forecasts about responses of indicators to management actions -Identify and assess key gaps in understanding 2--Design (Management Plan) -Design management plan that will provide reliable feedback and fill gaps in understanding -Evaluate management optiondaltemative designs, and choose one to implement -Design monitoring protocol -Plan data management and analysis -State how management actions or objectives will be adjusted -Set up system to communicate results and information 3-Implement -Follow the plan! Monitor implementation and document any deviations from plan 4-Monitor -Monitor for implementation, effectiveness, validation, and surprises -Follow the monitoring protocol designed in Step 2 5--EvaluatelAdjust -Compare outcomes to forecasts made in Step 1 -Document results and communicate them to others facing similar management issues 6-Adjust -Identify where uncertainties have been reduced and where they remain unsolved -Adjust the model used to forecast outcomes, so that it reflects the hypothesis supported by results -Adjust management actions and reevaluate objectives as necessary -Make new predictions, design new management experiments, test new options...repeat cycle SJRWMD Adaptive Management Step A set of viable alternatives was developed through a cooperative public process that maximized the participation and input of local governments, government-owned and privately owned utilities, self suppliers, and other interested and potentially affected parties. (Completed) The AM plan expands the existing hydrologic and environmental monitoring networks to better understand and assess the linkage between groundwater withdrawals and impacts to the surficial aquifer, wetlands and lake levels. (Completed, will be revised as needed). Implementation begins with an efficient network design with sufficient spatial coverage. (Network design is ongoing, installation of monitoring stations is underway) The monitoring network must supply information on climate, aquifers, and related resource factors. (Data collection from existing monitoring network is ongoing; network expansion is underway). Database support development and analysis capabilities are key elements of the planning process. (Under Development) Clearly defined outcome hypotheses are necessary in order to adaptively manage decision processes. An initial set of hypotheses and management assumptions were developed in Steps 1 and 2. (Under Development) Step 1-Assess the Problem The Water 2020 planning process was conducted in an open forum with multiple workshops conducted in multiple locations. Regional water supply plans were developed for each PWRCA. Those plans identify sustainable sources of supply that will meet projected water use demands while at the same time avoiding unacceptable adverse impacts to natural systems. Work groups of SJRWMD project staff and interested stakeholders made future water demand projections, identified future water supply deficits, developed and evaluated alternatives, and identified working alternatives for the regional water supply plan. A work group 249

4 typically included water supply utilities, agricultural water users, city and county governments, environmental organizations, state agencies, and interested citizens. The East Central Florida Work Group Area I identified a subset of six acceptable solutions that have the potential to meet projected 2020 water-use demands while protecting the water resource and dependent natural systems. These sets of alternatives serve as guidance for developing detailed implementation plans that address regional and utility-specific needs. The subset of six viable water-supply alternatives demonstrates that there is sufficient water available in east-central Florida to meet projected 2020 demands under varied conditions. The projections, however suggest that during the Water 2020 planning horizon, significant areas within east-central Florida will reach the limit of sustainable and safe withdrawals from the Floridan aquifer. Uncertainty was explicitly addressed in the Water 2020 planning process; it was associated with the prediction of future demands, the estimation of water supply deficits, and the estimation of costs for developing water supply options and alternatives. SJRWMD recognized that uncertainty can be managed in an adaptive management approach to the long term planning and decision process by: 1. Identifying the sources of uncertainty. 2. Defining the nature and effect of each source. 3. Managing each source to minimize its effect to the extent possible to minimize the effects of the entire set of uncertainties (optimization). Step %Design the Management Plan In 2001, SJRWMD developed an adaptive management plan for water resources within the District. The plan involves the coordination and expansion of the existing hydrologic and environmental monitoring network to better understand the linkage between groundwater withdrawals and lowering of surficial aquifer, wetland, and lake water levels. Investigations (SJRWMD 2000; SJRMWD unpublished data) have identified areas where adverse impacts are expected to occur. These areas will be intensely monitored to determine if predicted responses are in fact occumng, and to adjust modeling analysis to reflect the actual observations. Uncertainty management and reduction is an essential element of the management plan. Faced with the magnitude of the decisions that lay ahead and the uncertainty associated with the planning and decision making process, it is important to narrow the range of uncertainty while at the same time maintaining as much flexibility as possible. Investigations related to the development of alternative water supplies and the implementation of other management techniques will be conducted to narrow uncertainty associated with water supply planning and decision making throughout the SJRWMD. It will provide a framework for focusing attention on activities designed to reduce uncertainty and integrate these activities into the planning and decision making process. The ultimate goal is to provide for future water supply needs in the most cost-effective manner, while ensuring adequate protection for valued natural systems. The means by which learning occurs in AM is through hypothesis testing. In most AM applications alternative strategies or management policies provide testable hypotheses that are tentatively adopted to account for observed facts and guide investigation. An outcome of the Water 2020 planning is forecasts of future conditions of the water resource and predictions of responses of environmental indicators to management actions. From these a set of testable hypotheses emerge that will serve as a guide for testing under SJRWMDs adaptive management project. 1. Groundwater is a finite resource in the SJRWMD, the limit of sustainable withdrawals will be reached in the next 20 years in some critical areas, 2. The year 1995 defines a baseline hydrologic condition that assumes no regionally significant impacts to natural systems from historic water supply withdrawals had occurred. 3. At a local andor subregional level, there are areas within the SJRWMD that currently show GAS) declines due to water supply withdrawals. 4. The degree of sensitivity of a natural system to impacts from altered hydrologic regimes induced by water withdrawals is a function of its landscape setting. 5. Adverse impacts to natural systems, such as wetlands, lakes, streams, rivers, and springs can be avoided through the use of protective criteria, such as minimum flows and levels (MFLs). 6. Adverse impacts to some sensitive lake and wetland systems occur when, under long term, steady state conditions, mean water levels are reduced by 1 foot or more. For other lake and wetland systems, impacts cannot be assessed by a priori criteria because of variability in hydrologic sensitivity. 250

5 7. Local and regions1 declines in levels of the SAS can cause water level reductions in wetland and lakes, and can also cause flow reductions in flowing water systems. 8. Adverse impacts of SAS declines can be avoided through aquifer management strategies, such as water table recharge using reclaimed water or stormwater. 9. Monitoring can be used to manage the water resources of SJRWMD to meet the needs of natural systems and society: 10. Monitoring program can be used to reduce uncertainty in the water supply planning process by defining causal relationships between water withdrawals and flows and levels in other aquifers and natural systems. Step 3-Implement Management Plan The success of the adaptive management program depends on the focused design of an integrated, efficient monitoring network with sufficient spatial coverage to address regional and local needs. Information obtained from the network will increase understanding of the water resource system and the factors affecting the resource. Expand and improve an integrated water resources monitoring and data analysis program that supports and enhances the District adaptive management initiatives that provide for the following: (1) the sustainable, permitted uses of water, (2) protection of the water resource and dependent natural systems from harm, and (3) restoration and/or recovery of resources that have suffered unacceptable harm, and (4) improved decision making for long term planning and permitting. Meeting the needs of users should drive the design of a monitoring network. The typical historical uses of hydrologic and related water resources data include the following: Stage (water level) analysis, hydrologic model development and calibration Development of ecological benchmark relationships for setting MFLs and related types of resource protection constraints. Water resources management and optimization decisions Water supply planning-input to models, development of protective constraints Assess cause and effect relationships between and among hydrologic units Establish thresholds of impact Regulatory assessment and compliance-resource management permit compliance, mitigation success, and judge recovery from impact Criteria and methods development for water supply planning, resource management, or resource regulation Aquifer management Resource inventory and condition Trend analysis Implement optimized water resource monitoring network within the PWRCAs and other targeted areas in the next 5 years; and develop and operate needed data management systems within the next 2 years; and provide regional analysis to support planning and permitting to prevent adverse impacts to the water resource and those natural systems dependent on the resource. Step &Monitor The AMP has the specific objective of adaptively managing the water resource within the SJRWMD. Monitoring data will provide the feedback to support management decisions, as well as the means to assess resource conditions. A database will be at the heart of the project s information management system. In support of AMP, the database will perform two essential functions: Import and store raw data values and data from other systems (i.e,, import from permit and regulatory files) Provide an efficient and easy to use method for SJRWMD and non-sjrwmd personnel to determine what data are available, to visualize and review what is available, and to obtain copies in a variety of forms and formats. A water resources monitoring network must be able to provide the following information: Floridan aquifer-level (potentiometric surface), water quality 251

6 Intermediate aquifer-level surlicial Aquifer System-level Lakes-water level, water quality, biological community characterization and assessment Wetlands-water level, topographic profile, soil mapping and characterization, soil depth profile, biological community characterization and assessment Springs-flow, assessment Sinkholes-aquifer levels, location and condition of caverns water quality, levels in spring run, biological community characterization and Meteorological data -rainfall, evaporation, temperature, humidity, etc. Existing legal users-aquifer levels, water quality. Step &Evaluate Implementing the AMP will provide inputs for an array of evaluations and basic analyses, such as: - trend analyse-utlier analysis, change detection compared with other systems - hydrologic statistics-hydrographs, exceedence frequencies, duration curves, double mass curves, etc. - regression model for stage-combine rainfall, water levels; predictive model for average conditions - calibrate stage curves to transect data, relating the hydrology to the ecological communities - calibrate other models. The AMP will help to define the allowable range of ecological conditions and the threshold for change and establish the thresholds beyond which harm will occur. The AMP will also provide feedback on optimization and decision modeling for supply development. Some of the uses can be accomplished with customized database reporting tools, others will be accomplished with downloaded data ported to other applications software, and for the remaining uses, new special use applications will be developed. Step &Adjust Investigations conducted as part of Water 2020 have already identied areas where adverse impacts are expected to occur. These areas will be monitored intensively to determine if predicted responses are in fact occurring, and to adjust modeling analyses to reflect the actual observations. The AMP network data will be the basis of management decisions at both district-wide and subregional levels. The analysis of district-wide network data will provide policy makers an overview of water supply planning options including effects of induced stressors, such as groundwater withdrawals. Change - The Key To Long-Term Success Success in AM means continuing the six-step process to improve the management of water resources. Developing AM at SJRWMD is largely an effort to reorganize and improve water resource management efforts that have been ongoing for over 20 years. The great challenge will be the acceptance of change as an ongoing process. REFERENCES Nyberg, B An Introductory Guide to Adaptive Management. Prepared for British Columbia Forest Service, Victoria, B.C. Gray, A.N "Adaptive Ecosystem Management in the Pacific Northwest A Case Study from Coastal Oregon." Conservation Ecology 4(2). Johnson, B.L 'The Role of Adaptive Management as an Operational Approach for Resource Management Agencies." Conservation Ecology 2(2). Lee, KN Compass and Gyroscope: Integrating Science and Politics for the Environment. Washington, D.C.: Island Press. Lee, KN "Appraising Adaptive Management." Conservation Ecology 2(2)