N H I INSTITUTE NATURAL HERITAGE. FT1.08 The Global Potential for Major Water System Reoptimization to Restore Downstream Ecosystems and Livelihoods

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1 FT1.08 The Global Potential for Major Water System Reoptimization to Restore Downstream Ecosystems and Livelihoods

2 Extent of Major Dams Today: 49,000 large dams, two thirds in developing countries. 1,700 large dams are under construction in other parts of the world, primarily China and India. Pay more rigorous attention to maintaining biodiversity, and protecting ecosystems in the design and implementation of water projects.the water supply needs of rivers, wetlands, and fisheries will be considered in decisions concerning the operation of reservoirs and the allocation of water.

3 Extent & Location of Major Dams China Rest of Asia North America Western Europe Africa Eastern Europe South America Central America Austalasia Number of Large Dams

4 Irrigation: Half the world s large dams were built exclusively or primarily for irrigation.

5 Hydropower: Hydropower currently provides 19% of the world s total electricity supply and is used in over 150 countries.

6 Flood Control: Floods affected the lives of 65 million people per year, more than any other type of disaster, including war, drought and famine.

7 Environment: Today, dams must be reoptimized for other benefits: environmental performance and livelihoods.

8 It s Not Just a Matter of Water Volume. This is the same volume!

9 Impact of Dam Operations on Floodplains

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11 Impacts to Sediment Regime and Fluvial Morphology Radically alters transport and deposition of silt in floodplains, river channels, deltas and coastlines

12 Environmental Flow Assessments Becoming More Widely Adopted Environmental flow methodologies have been applied in 52 countries, including the following developing countries: obrazil ocambodia ocameroon ochile oindia oindonesia okenya olesotho omali omauritania omexico omozambique onamibia onigeria opakistan osenegal osouth Africa otanzania oturkey ozambia ozimbabwe

13 Balancing the Restoration Flow Demand and Supply Equation Objectives: Instream Conditions Floodplain Conditions Water management techniques to generate water when, where and in amounts desired. Parameters: Magnitude, Duration, Frequency, Location, Seasonality

14 Where Flow Restoration Provides Greatest Benefits Broad Alluvial Floodplains Wetlands Estuaries Deltas

15 The Toolkit for Dam Reoperation Irrigation dams: Relocating points of diversion and return flow Integrating groundwater and surface storage (conjunctive water management) Aquifer recharge and recovery (groundwater banking) Reductions in physical losses from irrigation systems Water transfer arrangements Retiring waterlogged or salinized lands

16 The Toolkit for Dam Reoperation Hydroelectric dams: Changing the role and function of the hydrodam in the mix of generation facilities for the grid Substitution of daily peaking facilities Re-regulation reservoirs downstream of hydroelectric dams Pumped storage facilities to reduce the need to operate dams to follow electrical load curves Better coordination of cascades of dams to permit more flexible operation

17 The Toolkit for Dam Reoperation Flood Management: Floodplain accommodations of seasonal inundations Flood easements Flood routing and storage in retention basins Levee setbacks

18 Rapid Assessment Tool for Selecting Promising Dams Dichotomous key

19 Rapid Assessment Tool for Selecting Promising Dams Dichotomous key

20 Regional Components

21 Project Partners in China Component Ministry of Water Resources Yellow River Conservancy Commission Yangtze Water Resources Commission Pearl River Commission Three Gorges Project Corporation Chinese Academy of Sciences Tsinghua University Global Water Partnership China Institute of Water Resources and Hydropower Research Oriental Environmental Institute World Wildlife Fund Institute for Food Policy Research (IFPRI) Shandong Province Department of Water Resources Guanxi Zhuang Autonomous Region Department of Water Resources Natural Heritage Institute

22 Eternal Spring City Sanmenxia Xiaolangdi Danjiangkou Three Gorges Longtan Li Jiang

23 Diama Dam Senegal River Faleme River Bafing Bafing River River Bakoye River Manantali Dam Black Black Volta Volta White White Volta Volta Tiga Dam Hadejia-Nguru wetlands Challawa Gorge Dam Lake Chad Akosombo Dam Lake Volta

24 Composition of Partnership Dam owners and operators River Basin Commissions National regulatory and planning agencies Governmental and university research institutes Local NGOs representing river basin communities International NGOs with high degree of technical capacity Water user interests

25 Products and Results Toolkit of reoperation techniques Rapid assessment tool List of promising dam reoperation targets Reoperation plans for selected dams A reoptimization investment plan Much improved sense of environmentally compatible siting, design and operations of new dams Durable network of expertise and activism

26 FT1.08 The Global Potential for Major Water System Reoptimization to Restore Downstream Ecosystems and Livelihoods