Assessing Water Quality for International Hydropower Projects

Transcription

1 Assessing Water Quality for International Hydropower Projects Insert then choose Picture select your picture. Right click your picture and Send to back. George A. Krallis Edward M. Buchak

2 Outline Context: International EHSIA s Need for hydropower in the developing world The role of funding agencies Impacts of interest Tools: ERM s Approach In-reservoir water quality modeling Downstream WQ modeling and calculations Inform design and operational considerations Biological and social implications Examples: Reventazón, Costa Rica Baynes, Namibia-Angola Trung Son, Vietnam

3 Need for Hydropower in the Developing World 3

4 The Role of Funding Agencies World Bank and International Finance Corporation (IFC) U.S. Agency for International Development (USAID) Overseas Private Investment Corporation (OPIC) U.S. Export-Import Bank (Ex-Im) Millennium Challenge Corporation (MCC) InterAmerican Development Bank (IDB) 4

5 Role of International EHSIAs IFC Environmental Health and Safety Guidelines Performance Standards 1-8, and The Equator Principles PS1: Assessment and Management of Environmental and Social Risks and Impacts PS2: Labor and Working Conditions PS3: Resource Efficiency and Pollution Prevention PS4: Community Health, Safety, and Security PS5: Land Acquisition and Involuntary Resettlement PS6: Biodiversity Conservation and Sustainable Management of Living Natural Resources PS7: Indigenous Peoples PS8: Cultural Heritage 5

6 Physical/Chemical Impacts of Interest In Reservoir Oxygen depletion Eutrophication GHG emissions Sediment trapping Water temperature Climate change Downstream of Reservoir Changes in the hydrologic regime, including permanently or occasionally dewatered reaches Oxygen-depleted, cold water releases Sediment starvation with episodic releases (flushing) 6

7 ERM s Approach Collect baseline data Field data and literature review (physical and chemical) Model in-reservoir water quality 3D or 2D hydrodynamic WQ models: GEMSS or CE-QUAL-W2 1D empirical trophic assessments: BATHTUB Perform downstream computations HEC-RAS, analytical calculations Assess biological and social implications IFIM, DRIFT 7

8 Example Reventazón, Costa Rica 8 Owner: ICE 305 MW Largest in Costa Rica: Height = 130 m Area = 6.90 km 2 (reservoir) 4.2 km diversion between dam and powerhouse Q min1 = 25 m 3 /s (@PS) Q min2 = 15 m 3 /s (@ dam) 4 th major dam on the Reventazón River Hot topics = sed and CC

9 Example Reventazón, Costa Rica Annual Averages - Model Results Water Temperature [ C] Dissolved Oxygen [mg/l] Inflow Outflow Difference

10 Example Baynes, Namibia-Angola Owner: Joint Namibia and Angola 400 MW Dimensions: Gross Head = 200 m Reservoir Area = 49 km 2 Q average = 160 m 3 /s Q min = 50 m 3 /s Major dam on Kunene River, an international border Vary intake structure to minimize impacts (DO) 10

11 Example Baynes, Namibia-Angola 11

12 Example Trung Son, Vietnam Owner: EVN 260 MW Dimensions: Head = 72 m Reservoir Area = km 2 4 Francis turbines Hot topic = GHG and clear/grub biomass prior to filling Technical transfer workshop in Vietnam 12

13 Example Trung Son, Vietnam 13

14 Thank You Insert then choose Picture select your picture. Right click your picture and Send to back.