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Tools and Techniques for Re-Optimizing Major Water Management Systems to Restore Aquatic Ecosystems and Human Livelihoods . Presented by The Natural Heritage Institute, IUCN, and the Nature Conservancy. IUCN World Conservation Congress – Barcelona October 9, 2008. Agenda. Introduction
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Tools and Techniques for Re-Optimizing Major Water Management Systems to Restore Aquatic Ecosystems and Human Livelihoods Presented by The Natural Heritage Institute, IUCN, and the Nature Conservancy IUCN World Conservation Congress – Barcelona October 9, 2008
Agenda • Introduction • Impacts of major water management systems • Dam re-optimization • Case studies • KomoduguYobe Basin Nigeria (Presented by Daniel K. Yawson, IUCN) • Savannah River: (Presented by Jeff Opperman, TNC) • REOP Group Exercise • Introduction to the Rapid Evaluation Tool for Reoptimization Potential (or REOP tool) of Hydropower Reservoirs • Conduct the group exercise • Feedback and Conclusions
Extent of Major Dams • 1949: 5,000 large dams, 1/4 in developing countries • 2008: 49,000 large dams, 2/3 in developing countries • Over the past two decades, the pace of dam building has declined in North America and Europe, where most of the technically attractive sites have already been developed. • 1,700 large dams are under construction outside of North America and Europe, primarily China and India.
Location & Distribution of Major Dams At end of 20th Century China Rest of Asia North America Western Europe Africa Eastern Europe South America Central America Australia Number of Large Dams
Purposes of Dams Irrigation:Half the world’s large dams were built exclusively or primarily for irrigation. Hydropower: Hydropower currently provides 19% of the world’s total electricity supply and is used in over 150 countries. Flood Control: Floods affect the lives of 65 million people per year—more than any other type of disaster, including war, drought, and famine.
Physical Transformation of Rivers Large dams alter flows and natural processes by: • Reducing flow during natural flood periods • Increasing flow during dry periods • Fragmenting the river system • Disconnecting rivers from floodplains, wetlands, deltas, and estuaries
Impact of Dam Operations on Natural Flow Patterns This is the same volume!
Effects on Downstream Livelihoods • Dams alter productive floodplains that support agriculture, the harvest of forest products, herding, and fishing (a critical source of protein for over 1 billion people). • “These social and environmental impacts are often disproportionately borne by poor people, indigenous people and other vulnerable groups.” • “. . . dams frequently entail a reallocation of benefits from local riparian users to new groups of beneficiaries at a regional or national level.” WCD, 2000.
Benefits of Reoptimizing Dam Operations • Hydropower • Irrigation Water Supply • Flood Control • Livelihood & Ecosystem • Restoration + The goal is enhancement of benefits, not reallocation.
Balancing the Restoration Flow Demand and Supply Equation Water management techniques togenerate water when, where and in amounts desired Objectives: Instream Conditions, Floodplain Conditions Parameters: Magnitude, Duration, Frequency, Location, Seasonality
Flow Restoration Provides Greatest Benefits to: Broad Alluvial Floodplains Wetlands Deltas Estuaries
Reoptimize Dam Operations • Create a flow pattern that more closely mimics the natural variability in flows. • Convert dams to “run-of-the-river” operations, re-creating an annual artificial flood. • Recharge the aquifer. • Facilitate climate change adaptation. • Re-operate the entire water management system—not just the storage component.
Objectives • Devise and demonstrate tools and techniques that can be applied major dams everywhere • Much improved sense of environmentally compatible siting, design and operations of new dams • Durable network of expertise and activism • Reduce risks associated with climate change
IUCN: "a just world that values and conserves nature" Why re-optimizing the Tiga and Challawa Gorge dams to restore human livelihoods and ecosystems in the Hadejia-Jama’are-Komadugu-Yobe-Lake Chad Basin? Presented by Daniel Kwesi YAWSON, Ph.D. (Project Coordinator, IUCN-KYB Project)
IUCN: "a just world that values and conserves nature" Outline of the Presentation The case study area The threats and the challenges What to do to address challenges What has been done so far (to date) What the re-optimization project intends to do or add
Nigeria; Niger & Other LCBC States/Nations IUCN: "a just world that values and conserves nature" The case study area
IUCN: "a just world that values and conserves nature" The case study area - 2 The KYB, covering an area of about 148,000 km2 of the semi-arid to arid sub-catchment of Lake Chad Basin, comprising north eastern Nigeria and south eastern Niger The main river sub-systems are the Yobe and the Komadugu, with the Yobe sub-system further divided into Hadejia River and Jama’are River sub-systems Some 15 million people depend directly or indirectly on the resources of the river, which sustains the livelihood of the majority through recession agriculture, pastoralism, fisheries activities, etc. As a shared resource, water is a potential source of conflict (e.g. farmers versus herders), but also a key state and regional integrating factor
IUCN: "a just world that values and conserves nature" The threats and the challenges Fast-growing water demand and inequitable access to water resources Fragmented regulatory responsibilities Lack of reliable hydro-meteorological information Uncoordinated development interventions Growing tensions and risks of conflicts Reduced river flow due to climate variability and change Environmental degradation
IUCN: "a just world that values and conserves nature" What to do to address challenges (long-term): an integrated development of the land, water and living resources of the basin so as to promote their sustainable use, conservation and equity (medium-term): fairer and more judicious allocation of water resources between competing sectors and the regions e.g. re-optimization of the large dams in the basin to satisfy downstream users as well (short-term): the clarification and strengthening of water management-related rules and regulations (short-term): the establishment of a regulatory body at the basin level (short-term): the establishment of a platform for weighing competing water demands
IUCN: "a just world that values and conserves nature" What to do to address challenges - 2 (short-term): establishment of an institutional framework for decision-making at the basin (short-term): improvement of data quality and availability, which required first that existing information base be compiled, rescued, synthesized, updated, and gaps identified and filled (short-term): a Grand Vision and an Water Management Plan for the basin (short-term): need for a common understanding of the basin-level big picture issues among stakeholder groups
IUCN: "a just world that values and conserves nature" What has been done so far (to date) Socio-economic & environment study and comprehensive water audit to facilitate dialogue Development of Catchment Management Plan with the establishment of a Trust Fund to actualize the Plan About to be signed “Water Charter” to regulate the resource Some pilot activities to demonstrate best practices By and large, the short-term challenges are under control by way of improving the institutional framework of land and water management in the basin
Upstream Upstream Damming Damming Downstream Downstream Most River Systems: Gaining River The KYB Case: Losing River IUCN: "a just world that values and conserves nature" What the re-optimization project intends to do or add
IUCN: "a just world that values and conserves nature" What the re-optimization project intends to do or add - 2 To address the medium- to long-term challenges Using run-of-the-river approach (as much as possible) to maintain or revive the floodplain activities and the wetlands sustenance (i.e. by way of ecosystem assessments). Thus, operating more as a run-of-the river facility and less as a storage facility To alter downstream ecology, sediment effects and affecting freshwater ecosystems to as much as possible to pre-dam construction era Surface water-groundwater conjuncture use Having the stakeholders in the project activities and they are to propose and select the planning model for the basin
Growing Population Growing Economy Increasing Demand for water Increased Competition for scarce water Need for equitable allocation and conflict resolution IUCN: "a just world that values and conserves nature" Conclusion
IUCN: "a just world that values and conserves nature" With Actualization of Project
Developing and Implementing Environmental Flows: The Savannah River (Georgia, USA) Jeff Opperman The Nature Conservancy October 9, 2008
The Savannah River Basin • Flood control • Hydropower • Water supply Total Drainage Basin Area -10580 sq miles
Thurmond Dam Russell Dam Hartwell Dam 1900 1950 2000
1b. Background work: IHA; summary report 1. Estimate flow requirements 1a. Stakeholder ID, kickoff, define ecosystem goals 2. Determine influence of human activities
1c. Flows Workshop 1b. Background work: IHA; summary report 1. Estimate flow requirements 1a. Stakeholder ID, kickoff, define ecosystem goals 2. Determine influence of human activities
Environmental Flow Workshop Structure Flood • EFRs for: • Dry years • Average years • Wet years Shoals High Pulse Low Flow Flood Unified Flood Full Group Floodplain HighPulse Unified High Low Flow Unified Low Flood • Defined by: • Magnitude • Frequency • Timing • Duration • Rate of change Estuary High Pulse Low Flow
1c. Flows Workshop 1b. Background work: IHA; summary report 1. Estimate flow requirements 1a. Stakeholder ID, kickoff, define ecosystem goals 2. Determine influence of human activities Preliminary Flow Requirements
Environmental Flow Recommendations Savannah River, USA (below Thurmond Dam) • Details: • 20,000-40,000 cfs; 2-3 days, 1/month • Purposes: • Provide predator-free habitat for birds • Disperse tree seeds • Transport fish larvae • Flush woody debris from floodplain to channel • Floodplain access for fish • Fish passage past NSBLD Key Wet Year Avg Year Dry Year • 50,000-70,000 cfs; 2 weeks, avg every 2 yrs • Maintain channel habitats • Create floodplain topographic relief • Provide fish access to the floodplain • control invasive species • Maintain wetlands and fill oxbows and sloughs • Enhance nutrient cycling & improve water clarity • Disperse tree seeds Floods >30,000 cfs; 5 pulses, >2 days with 2 events of 2 week duration (March and early April) • 20,000-40,000 cfs; 2-3 days, 1/month • Provide predator-free habitat for birds • Disperse tree seeds • Transport fish larvae • Flush woody debris from floodplain to channel • Floodplain access for fish • Fish passage past NSBLD High Flow Pulses • <13,000 cfs; 3 successive years, every 10-20 years • Floodplain tree recruitment • 8,000-12,000 cfs; • Exchange water with oxbows Low Flows • >8,000 cfs • Larval drift for pelagic spawners • <5,000 cfs • Adequate floodplain drainage • Create shallow water habitat for small-bodied fish • 3,000 cfs; 3 successive years every 10-20 years • Floodplain tree recruitment JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
1c. Flows Workshop 1b. Background work: IHA; summary report Incompatibilities 4. Collaborative dialogue to search for solutions; Modeling and research Solutions 3. Identify opportunities and incompatibilities for flow implementation Opportunities 5a. Implement flows 5b. Research and monitoring of flows 1. Estimate flow requirements 1a. Stakeholder ID, kickoff, define ecosystem goals 2. Determine influence of human activities Preliminary Flow Requirements
Implementing and monitoring high flow pulses on the Savannah
1c. Flows Workshop 1b. Background work: IHA; summary report Incompatibilities 4. Collaborative dialogue to search for solutions; Modeling and research Solutions 3. Identify opportunities and incompatibilities for flow implementation Opportunities 5a. Implement flows 6. Adaptive management and institutional/policy adaptations 5b. Research and monitoring of flows Refined Ecosystem Flow Requirements 1. Estimate flow requirements 1a. Stakeholder ID, kickoff, define ecosystem goals 2. Determine influence of human activities Preliminary Flow Requirements
Savannah River2004-2008 • E-flows defined <1 year; $90,000US • Changed reservoir operations e-flows partly implemented helping guide real-time reservoir operations • Monitoring & research to support adaptive management river, floodplain, estuary • Modeling HEC-ResSim, HEC-EFM • Redefined the engineer-scientist relationship
Rapid Evaluation Tool for Reoptimization Potential (REOP tool) What is the REOP tool? What is its purpose & scope? Does it target particular dams?
REOP Exercise • Instructions: • Using the information sheet & watershed sketch as a guide, apply the REOP tool to determine which dams are candidates for reoptimization. • If a “NO” answer is achieved, cross off that dam and continue to the next one. • If a “YES” answer is achieved, move to the next level of the REOP decision-tree until the dam is eliminated or is determined to be a promising candidate.
Rapid Evaluation Tool for Reoptimization Potential of Hydropower Reservoirs Not a high priority for reoperation. No Does the facility generate power at the dam site (rather than by diversion of water to downstream or transbasin powerhouse)? Yes ENVIRONMENTAL BENEFITS No Does the dam control flows affecting floodplains, riparian zones, wetlands, deltas or estuaries that are productive for food production or ecosystem processes or would environmental flows within the downstream channel restore socially valued or endangered species? Yes STORAGE VS. RUN-OF-RIVER No Is the active storage capacity of the reservoir more than 25% * of the mean annual inflow? Yes No Can land uses in the down-stream floodplain be modified/ managed to accommodate controlled flood events? Yes Not a high priority for reoperation. Are other dams in the cascade operated by the same power company? Is the dam one of a complex or cascade of hydropower dams in the same basin? Yes No No Are there alternative sources of thermal power in the existing grid that can supplant some fraction of hydropower during seasonal low runoff periods? Are there alternative sources of thermal power in adjacent grids that can supplant some fraction of hydro-power during seasonal low runoff periods? No No Yes Yes Yes Consider Rescheduling Hydropower Generation & Source Shifting as reoperation strategies Consider Power Grid Interconnection as a reoperation strategy Consider coordinated basin wide reoperation of the dam complex or cascade * Provisional figure depending on local conditions.
11 8 9 Wetland #2 Orchard 10 12 Annual crops Wetland #1 7 “Catville” Native Comm. 5 6 Endangered Species Habitat “Dogville” 3 Delta 2 4 1 Artist: Lisa McCarrel Numbers for dams correspond to numbers on Dam Stats table.
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