The se san and nam theun nam kading hydropower dam cascades


Published on

3rd Mekong Forum on Water, Food & Energy 2013. Presentation from Session 9: Managing the impacts of dams across cascades.

Published in: Technology
  • Be the first to comment

  • Be the first to like this

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide
  • High number of fish speciesThe catchment is geologically diverse, with rocks of alluvial, sedimentary and igneous origin. A corridor of red conglomerated sandstone, siltstone and clay stone run on each side of the NTNK from the source to the confluence with the Mekong. Parallel to this, to the north and south, are Carboniferous and Devonian pavement and karsts limestone uplands, with isolated granite extrusions
  • In Gia Lai – 72 dams – a complex network of hydropower facilities – each dam requires access roads and transmission lines
  • The se san and nam theun nam kading hydropower dam cascades

    1. 1. The Se San and Nam Theun/Nam Kading Hydropower Dam Cascades Managing for sustainability Jeremy Carew-Reid, Peter Ward and Peter-John Meynell 1
    2. 2. Nam Theun/Nam Kading Basins 2
    3. 3. Se San Basin Gia Lai  Large HP projects (> 30 MW): 6  Small HP projects (<30 MW): 74  Built: 33 projects  Planned: 41  Gia Lai authority revoked 9 projects Kon Tum  Large HP projects (> 30 MW): 2  Small HP projects (<30 MW): 44  Built: 9 projects  Planned: 14  Kon Tum authority revoked 21 projects • Vietnam (64%) – Kon Tum and Gia Lai • Cambodia (36%) - Ratanakiri and Stung Treng • Catchment of 17,100 km2 3
    5. 5. Location of cascades Key characteristics of cascades areas: • Geographically and institutionally isolated and poorly serviced • Very high proportion of ethnic minority communities • Very high poverty levels in affected communes • Very high biodiversity importance • Relatively high projected climate change threats 5
    6. 6. Poverty and hydropower Catchment Se San Nam Theun Nam Kading Province Ethnic Minorities % of population Poverty % Ethnic Minority Poverty % Kon Tum Gia Lai Ratanak Kiri 54 45 80 29 25 44 74 74 Very High Stung Treng Bolikhamxay Xiang Khouang 15 28 52 47 52 55 Very High Very High Very High 6
    7. 7. Poverty and hydropower Isolated communities with high poverty incidence and ethnic minority populations Gia Lai Kon Tum 7 Ethnic minorities 45% 54%
    8. 8. Se San - biodiversity • 8
    9. 9. Nam Theun/Nam Kading: biodiversity 9
    10. 10. Climate Change – Temperature and Rainfall 10
    11. 11. 8-9% increase in rainfall across the Se San basin Comfort zones 11
    12. 12. Comfort zones 12
    14. 14. Impacts of existing and planned cascade dams in Se San and Nam Theun - Nam Kading In the affected areas, the cascades have:  Reduced agricultural land area and production  Required extensive resettlements and dislocation  Aggravated local poverty reduction efforts and quality of life indicators especially in ethnic minority communities  Reduced biodiversity especially habitat complexity and species  Failed to consider the significant implications of climate change 14
    15. 15. Ecological impacts of the cascades (all with livelihood and social wellbeing implications) Alteration of natural water flow regimes has: • Severely modified and reduced channel and floodplain habitats; • Disrupted timing of reproduction and other life cycle stages in aquatic species; • Broken lateral and longitudinal hydraulic connectivity; • Facilitated invasion of exotic and introduced species 15
    16. 16. IMPROVING CASCADE PERFORMANCE Agree on where we want to go – then we can decide how best to get there 16
    17. 17. Where are we going? Sign posts for cascade sustainability Broad management goals for dam reoperation: 1. 2. 3. 4. 5. 6. Mimicking natural flow conditions Reactivating natural flood pulse and flow into floodplain forests, wetlands and designated agricultural areas to reactivate natural flood storage, nutrient disbursement , water purification benefits and ecological benefits Recovering fish and other wildlife populations valued for livelihoods and biodiversity Regaining habitat complexity by restoring the dynamic balance between river erosion and sedimentation, Restoring watershed condition and enhancing agricultural productivity Arresting and reversing losses in ecosystem and social integrity associated with a) b) c) geomorphic imbalances; cultural and spiritual uses of rivers; and other socially valued products and services. 17
    18. 18. Specific reoperation objectives For each of the broad goals need reoperation objectives/tasks which: 1. Are specific to the river and cascade 2. Have measurable target levels 3. Have specific dates for phased achievement, 4. Include target which can be achieved almost immediately. 5. Define monitoring methods and frequency of data collection 6. Define institutional responsibilities 18
    19. 19. Regaining habitat complexity and biodiversity Specific reoperation objectives • Se San – the most important migratory fish for catch has gone from the river - Henicorhynchus (2 species) – objective: (i) re-establishing upstream migration for spawning of these indicator species (eg by creating natural fish passes) (ii) establishing sustainable populations • Nam Theun - Nam Kading (fish migration may not be feasible) – objective: establishing natural fish biodiversity in reservoirs (increase spawning habitats and access to tributaries for native species) – need indicator species 19
    20. 20. Maintaining social and cultural diversity Specific reoperation objectives Objectives: 1. Identify and maintain sacred places in the river channels (eg waterfalls, islands, rapids, deep pools) 2. Establish community user groups for specific places (eg fish conservation zones within and outside reservoirs – artificial wetlands and natural deep pools) 3. Establish benefit sharing cascade funds to go long term to effected communities 4. Payment for ecosystem services to upstream watershed management communities 20
    21. 21. Reactivating natural flood flow Specific reoperation objectives Objectives 1. Identify and create flood relief areas on original flood plain (total area, timing of floods and management precautions) 2. Retain wetland ecosystem functioning 3. Mimic natural flood seasonality (eg for triggering fish migration) 21
    22. 22. Restoring geomorphic imbalances Specific reoperation objectives Objectives: 1. Increase sediment and nutrient mobilisation for maintaining habitats and conditions for productive use (habitat stability, access, navigation) (restoring natural conditions not feasible) 2. Mimic natural seasonal sediment/nutrient content conditions 3. Maintain channel morphology and flushing by coordinated seasonal short high intensity flow releases (eg confluence of Nam Kading with Mekong) 22
    23. 23. Increasing agricultural production Specific reoperation objectives Objectives Dam reoperation: 1. increase area of irrigated land (eg total potential irrigable area in Se San is estimated at 28,348 ha) 2. Increase productivity from existing agricultural land through appropriate irrigation regime (eg Se San needs wet season irrigation) 3. Reservoir routing – reducing reservoir height prior to floods (to mimic river flood conditions within reservoir) Enhancing life of cascade reservoirs: 1. Reducing agricultural cultivation from unsuitable uplands 2. Increase forest cover and reduce soil erosion in uplands 23
    24. 24. INSTITUTIONAL PREREQUISITES FOR CASCADE SUSTAINABILITY Achieving the reoperation objectives 24
    25. 25. Institutional and management challenges • Need to move towards realising one foundation principle: Main obstacles: 1. Many plans and policies (with inconsistent and competing objectives) 2. Many agencies (with defuse and overlapping authority) 3. Single project orientation 25
    26. 26. Nine obstacles to sustainability 1. A single project by project approach to development 2. No plans by river basin including all small, medium and large scale projects 3. Limited cumulative and strategic environmental assessment 4. Too many agencies with overlapping and inconsistent mandates and limited coordination and regulatory control 5. Private sector companies dominate river management 6. Lack of transparency in planning and decision making 7. Limited enforcement of environmental plans and safeguards 8. Lack of community participation in planning, assessment and management 9. Short term perspective on financial and technical support to affected communities and ecosystems 26
    27. 27. Nine management responses for sustainability 1. 2. 3. A river basin agreement A river basin management plan A river basin regulatory authority to ensure: a) b) c) 4. 5. 6. 7. 8. 9. Predictability of flows Rigor and competence in strategy and techniques in managing flood flows Adherence to environmental and benefit sharing plans A conservation off set arrangement and investment fund A benefit sharing arrangement A long term horizon in financing and support An ongoing monitoring and response program to meet local community and ecosystem needs An open and transparent appeals mechanism Expanded flood and flushing arrangements and environmental flows 27
    28. 28. River Basin agreements 1. Se San River Basin Management International agreement between Vietnam and Cambodia 2. Nam Theun/Nam Kading River basin management policy • Setting out broad management goals and specific reoperation objectives covering: 1) power production; 2) ecological restoration and maintenance and 3) social diversity and benefit sharing • An iterative process including design, negotiation and redesign to achieve the agreed objectives 28
    29. 29. River basin management plans Setting out: 1. The goals and objectives 2. What will be constructed, when and where 3. Managing and regulating arrangements 4. The tasks for to achieve a balance in the three main objectives – power production, ecological maintenance and social equity 5. The distribution of financial benefits 6. Monitoring and evaluation program 7. Institutional arrangements, responsibilities and timing 29
    30. 30. Cascade plan governing principles • Net provincial economic gain: Provincial economies should not be left worse off by the plan • User pays: HP operators should contribute to meeting all direct and indirect environmental and socio-economic costs of the plan implementation in the long term • Multiple use: HP projects with reservoirs should be designed and managed for multiple use of water resources • Safe operations: Implement operational regimes and institutional arrangements to reduce droughts and floods and prepare for disasters • Net biodiversity gain: Avoid and minimize harm to biodiversity and introduce conservation offsets • Net gain in minority well being: Reduce poverty and increase food security in affected minorities • The precautionary principle: Take care to avoid permanent loss of provincial assets 30
    31. 31. Thank you 31