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Technical Assistance Consultant’s Report Project Number: 40514 February 2008 Lao People’s Democratic Republic: Preparing the Cumulative Impact Assessment for the Nam Ngum Hydropower Project (Financed by the Japan Special Fund) Prepared by Vattenfall Power Consultant AB in association with Ramboll Natura AB and Earth Systems Lao This consultant’s report does not necessarily reflect the views of ADB or the Government concerned, and ADB and the Government cannot be held liable for its contents (For project preparatory technical assistance: All the views expressed herein may not be incorporated into the proposed project’s design Stockholm, 29 February, 2008 To: Asian Development Bank The Director, SEID Mr John R Cooney ADB Avenue, Mandaluyong City 1550 Metro Manila Philippines Re: PPTA TA4921-LAO Preparing the Cumulative Impact Assessment for the Nam Ngum Hydropower Project Final CIA Report Dear Sir, Please find enclosed 10 hard copies and three CDs with pdf files of the main report and the five appendices of the Final CIA Report for the above mentioned TA Yours sincerely, Dr Bernt Rydgren, Team Leader Vattenfall Power Consultant AB Box 1842, SE-581 17, Linköping Sweden Phone: +46-70-3160920 E-mail: bernt.rydgren@vattenfall.com TA 4921-LAO: Preparing the Cumulative Impact Assessment for the Nam Ngum Hydropower Project Components A, parts and Final CIA Report Main Report February, 2008 Vattenfall Power Consultant AB in association with Ramboll Natura AB and Earth Systems Lao TABLE OF CONTENTS EXECUTIVE SUMMARY V BACKGROUND V DEVELOPMENT SCENARIOS AND IMPACT ZONES USED IN THE ASSESSMENT V EXPECTED SECTORAL DEVELOPMENTS IN THE NAM NGUM RIVER BASIN TO THE YEAR 2020 VI SUMMARY OF IDENTIFIED IMPACTS FOR THE DEVELOPMENT SCENARIOS IX SUMMARY OF STRATEGIC CONCLUSIONS AND RECOMMENDATIONS XVI 1.1 1.2 1.3 1.4 1.5 1.6 2.1 2.2 2.3 2.4 2.5 3.1 3.2 3.3 4.1 4.2 4.3 5.1 5.2 5.3 5.4 5.5 5.6 5.7 INTRODUCTION OBJECTIVE OF THE TECHNICAL ASSISTANCE PROJECT CUMULATIVE IMPACT ASSESSMENT AND CATCHMENT-WIDE STRATEGIC ENVIRONMENTAL STUDIES– THEORY AND SELECTED APPROACH STRATEGIC ENVIRONMENTAL ASSESSMENT OF LAO HYDROPOWER DEVELOPMENT HYDROPOWER DEVELOPMENT IN LAO PDR LEGAL FRAMEWORK AND GUIDELINES RELEVANT FOR ENVIRONMENTAL ASSESSMENTS OF HYDROPOWER IN LAO PDR NOTE ON ADMINISTRATIVE DIVISIONS IN THE NAM NGUM RIVER BASIN AND SPELLING OF LAO WORDS ENVIRONMENTAL AND SOCIO-ECONOMIC BASELINE CLIMATE AND WATER RESOURCES LAND USE AND AGRICULTURE 11 ECOLOGY 12 MINING 14 PEOPLE AND LIVELIHOODS 14 HYDROPOWER IN THE NAM NGUM BASIN 16 EXISTING AND FUTURE HYDROPOWER PROJECTS IN THE NAM NGUM BASIN 16 NAM NGUM HYDROPOWER PROJECT 18 SIMPLIFIED EFFICIENCY INDICATORS FOR THE PROJECTS IN OUR DEVELOPMENT SCENARIOS 18 DEVELOPMENT SCENARIOS AND IMPACT ZONES 21 BACKGROUND 21 THE SCENARIOS 21 IMPACT ZONES 22 FINDINGS 25 ESTIMATION OF HYDROLOGICAL IMPACTS OF FUTURE DEVELOPMENTS 25 ENERGY PRODUCTION IN THE NAM NGUM RIVER BASIN 32 REVIEW OF THE RIVER BASIN HYDROLOGICAL MODEL MORDOR AND THE HYDROPOWER SIMULATION MODEL PARSIFAL 38 CLIMATE CHANGE 39 LAO-THAI WATER TRANSFER 42 REVIEW OF POLICIES AND LEGAL FRAMEWORK DOCUMENTS SPECIFICALLY FOR SOCIAL AND ENVIRONMENTAL ASSESSMENT OF HYDROPOWER IN LAO PDR 42 FOLLOW-UP OF RECOMMENDATIONS FROM STRATEGIC ASSESSMENT OF 2004 45 ADB TA 4921-LAO: Preparing the Cumulative Impact Assessment for the Nam Ngum Hydropower Project Components A, parts and 2, Final CIA Report i 5.8 5.9 6.1 6.2 6.3 6.4 6.5 6.6 6.7 6.8 6.9 6.10 6.11 SECTORAL TRENDS 46 IMPACT STATEMENTS FOR THE DIFFERENT DEVELOPMENT SCENARIOS 57 GENERAL CONCLUSIONS AND RECOMMENDATIONS OF A STRATEGIC NATURE 66 PRIORITISED RECOMMENDATIONS FOR URGENT IMPLEMENTATION 66 ENGINEERING HYDROLOGY AND HYDROPOWER PRODUCTION 67 WATER RESOURCES 69 WATER QUALITY 70 LAND MANAGEMENT AND LAND USE 72 IRRIGATION DEVELOPMENT 73 POLICY AND PLANNING 74 AQUATIC ECOLOGY 80 TERRESTRIAL ECOLOGY 82 MINING 84 SOCIO-ECONOMY AND POVERTY ISSUES 85 BIBLIOGRAPHY 89 ABBREVIATIONS 97 PEOPLE CONSULTED 100 10 THE CONSULTING TEAM 103 APPENDICES: APPENDIX A: BASELINE FOR THE BIO-PHYSICAL ENVIRONMENT APPENDIX B: PEOPLE AND LIVELIHOODS IN THE NAM NGUM RIVER BASIN APPENDIX C: MONITORING PROGRAMMES APPENDIX D: HYDROPOWER GENERATION STUDIES APPENDIX E: DETAILED IMPACT STATEMENT ii ADB TA 4921-LAO: Preparing the Cumulative Impact Assessment for the Nam Ngum Hydropower Project Components A, parts and 2, Final CIA Report Acknowledgements This report has been prepared by Vattenfall Power Consultant AB, in association with Ramboll Natura AB and Earth Systems Lao It has been prepared as a Technical Assistance project with funding from the Asian Development Bank It is impossible to mention all the people that have assisted us in the preparation of this report The list of people consulted, at the end of this report, provides an attempt at thanking those who have provided assistance, but we know the list is likely incomplete We, therefore, wish to extend our gratitude to each and everyone who have contributed to this report However, the responsibility for the conclusions drawn rests entirely with ourselves Some people and organisations have been particularly helpful and deserve special mention here These are, in no particular order: The staff at the Executing Agency for the study – the Department of Electricity, notably its Social and Environmental Management Division under the leadership of Mr Chantho Milattanapheng; The staff of the Nam Ngum River Basin Development Sector Project under the leadership of Dr Alf Birch; The Information Center; IWMU, MAF through Dr Thatheva Saphangthong; ADB staff in Vientiane, Hanoi and Manila; Jeremy Bird, consultant, ADB; The Department of Energy Promotion and Development; the FIPD MAF through Mr Khamma; as well as other staff at MAF; WREA; MRC; WWF; and the WCS ADB TA 4921-LAO: Preparing the Cumulative Impact Assessment for the Nam Ngum Hydropower Project Components A, parts and 2, Final CIA Report iii iv ADB TA 4921-LAO: Preparing the Cumulative Impact Assessment for the Nam Ngum Hydropower Project Components A, parts and 2, Final CIA Report Executive Summary This study is based on analyses of secondary information only, due to circumstances beyond the control of the consultants Background The overall purpose of this consultancy assignment is to assist ADB in its preparations for financing of the proposed Nam Ngum Hydropower Project (NN3), located in the Nam Ngum River Basin (NNRB) in Vientiane Province, in central Lao PDR The key outcome is, therefore, a strategic assessment of the entire Nam Ngum basin and the expected cumulative impacts of the extensive hydropower development programme identified for the basin The Technical Assistance project (TA) consists of two components This report deals with component A The implementation of component B is totally separated from the activity described herein, and will not be further commented upon Component A deals with two main tasks, that of: a) a “cumulative impact assessment” for the NN3 project in accordance with the ToR (ADB, 2007c); and b) the design and implementation of a medium-term environmental monitoring programme for the river catchment, focussed on water-quality and aquatic ecology, to be run under project financing until the end of the year 2009 The work is closely related to another ADB project, the Nam Ngum River Basin Development Sector Project (NNRBDSP) and close co-operation between the two activities has been an important mean to achieve the objectives The theoretical distinction between cumulative impact assessment, as defined by the ADB in the ToR, and strategic environmental assessment (SEA), varies among different experts and organisations The consultant has, in this study, interpreted the overall emphasis of our ToR such that we focus our work on a strategic-level basin-wide study of the social and environmental impacts of hydropower development and related major developments The ToR are very clear on the concept of a basin-wide study, looking at the water resources of the entire Nam Ngum catchment, based on scenarios This is well supported by the approach of the NNRBDSP Development Scenarios and Impact Zones Used in the Assessment In co-operation with experts from the NNRBDSP, we have developed three main development scenarios, with attention paid to future changes in hydropower and irrigation They are: • Scenario 1: Present situation plus Nam Ngum hydropower plant plus 61 000 of pumped irrigation, mainly in the Vientiane Plains (down-stream of all hydropower plants included in this study); • Scenario 2: Scenario plus Nam Ngum hydropower plant and; • Scenario 3: Scenario plus Nam Ngum 5, Nam Lik and 2, Nam Bak and as well as 39 000 additional of gravity-fed irrigation These scenarios are assessed for two different time horizons; 2013 and 2020, yielding separate scenarios, 1a for scenario in 2013, 1b for scenario in 2020, and so on These years have been chosen because 2013 is the year when most of the additional hydropower, ADB TA 4921-LAO: Preparing the Cumulative Impact Assessment for the Nam Ngum Hydropower Project Components A, parts and 2, Final CIA Report v including Nam Ngum 3, is planned to go on line, and 2020 is the end year of the Lao PDR government’s long-term strategic planning horizon It is important to recognise that a scenario is usually not a definite plan, or expected outcome Thus it is not the most likely future development, but rather a range of conditions which are suitable for analysis of the included parameters Instead, our scenarios are those that best respond to our need for scenario-based impact assessment at the basin level The goal of the assessment is indicative conclusions on strategic priorities, not an actual prediction of the expected outcome To facilitate the impact assessment for the scenarios, four impact zones were identified The reason for not using the, in hydropower environmental assessments, standard approach of upstream, downstream and immediate reservoir area as the main impact zones for assessment is quite straightforward With the number of planned hydropower plants in the basin, we would have ended up with not only an unmanageable number of impact zones, but also overlapping ones Thus, the four adopted impact zones were selected based on the sub-basins identified under the NNRBDSP, with a view to group them according to their natural environments They are shown in a map on the next page The zones are described in detail in the main report, see section Expected Sectoral Developments in the Nam Ngum River Basin to the year 2020 Water resources The main water users are hydropower and irrigation, with mining, domestic and industrial uses using, relatively speaking, minor quantities The predicted additional (extractive) uses in the hydropower sector (as evaporation from reservoirs), is around 1.5 m3/s, and the irrigation sector will use an estimate m3/s These figures are additional use (compared to present-day situation) for the entire basin in scenario 3b (scenario in 2020) Water quality will be affected, severely in many parts, due to the growing number of deep reservoirs with bottom-level intakes Hydropower The hydropower sector is developing very fast in Lao PDR The realistic situation in the Nam Ngum catchment in 2020 is between approximately 500 and 800 MW of installed hydroelectric generating capacity, excluding inter-basin-transfer projects This should be compared with the 255 MW in place at the time of writing, in 2007 This will generate somewhere between 500 and 000 GWh of electrical energy per year Land use and irrigation During the coming decade, as the area of swidden agriculture decreases, it is anticipated that there will be a forest regeneration in fields that were previously cultivated under the traditional rotational fallow system Over time, these regenerating forest areas are expected to revert to more dense forest There will also be an expansion of paddy land and commercial tree planting There will be a moderate increase in grassland (grazing) areas vi ADB TA 4921-LAO: Preparing the Cumulative Impact Assessment for the Nam Ngum Hydropower Project Components A, parts and 2, Final CIA Report Health tional systems and making use of it; • More people then before have access to infrastructural improvements (roads, markets, electricity) Nam Lik – Nam Xong (3) Negative impacts NN2 Resettlement • It is expected that parts of the NN2 resettlers will not be able to make a living from agricultural production alone, and have to rely on wage labour in plantations (including women and children), on work in fields of better-off farmers, on temporary or permanent work in urban areas (construction and service sector) Positive Impacts NN2 Resettlement • It is anticipated that parts of the resettled villagers have adjusted economically, socially and culturally to their new environment, taking advantage of new opportunities Lower Nam Ngum (4) • See scenario 1a NN2 • Medium to high impact on malnutrition and HIV/AIDS; • Medium impact on other STIs; • Low to medium impact on stress-related diseases and problems on the resettled population; • Low impact on TB and drowning NN3 • Medium to high impact on HIV/AIDS; • Medium impact on malnutrition; • Low to medium impact on other STIs; • Low impact on TB and drowning NN1 • Medium to high impact on HIV/AIDS; • Medium impact on malnutrition; • Low to medium impact on other STIs; • Low impact on TB and drowning ADB TA 4921-LAO: Preparing the Cumulative Impact Assessment for the Nam Ngum Hydropower Project Components A, parts and 2, Final CIA Report, Appendix E E:21 E.5 Scenario 3a, Present situation + NN2, NN3, NN5, NL1, NL2, NB1 and NB2 and 61 000 additional of pumped irrigation and 39 000 of gravity-fed irrigation in 2013 Sector Direct and Indirect Impacts Water Resources Upper Nam Ngum: (1) • We treat the NN3 reservoir under Impact Zone 2, even if it borders on two zones Mid Nam Ngum (2) • Increased evaporation from to the new reservoirs; • Large daily fluctuations in the water discharge from the power stations will have a negative impact on downstream areas; • Less water will be discharged to downstream reservoirs during the filling of new ones Nam Lik –Nam Xong (3) Fuang District Re-settlement Area: • Resettlement of villagers from the NN2-affected areas to the Fuang District and development of irrigation systems to support the livelihood of resettled villagers are likely to increase pressure on water resources, e.g diversion of water for irrigation and domestic use; • The ground water resources in this area might be affected if the high influx of new residents result in heavy use of pumped groundwater supply Other areas: • Increased evaporation from to the new reservoirs; • Large daily fluctuations in the water discharge from the NL1 and NL2 power stations will have a negative impact on the downstream areas; • Less water will be discharged to downstream areas during the filling of the NL2 reservoir Lower Nam Ngum (4) • Sediment transport in the Nam Ngum River downstream of the confluence of the Nam Ngum and Nam Lik rivers will likely have been reduced significantly Mid Nam Ngum (2) • Increased total suspended solids (TSS) and turbidity as a result of slides that will occur along the new reservoirs during the first year(s) One key factor for this, mainly in the cases of NN3 and NN5, is the steep valley sides and the rapidly fluctuating water levels in the reservoir; • Thermal stratification in the NN2 reservoir is likely to occur especially during the dry seasons (December to April) Stratification in the reservoir could result in the release of water which is relatively cool, low in dissolved oxygen and slightly acidic into the NN1 reservoir With a relatively low dilution factor from Nam Bak, water quality in the NN1 reservoir is likely to be negatively affected; • Thermal stratification is likely to develop also in the NN3 and NN5 reservoirs, which will affect the water quality downstream; • NN3 acts as a sediment trap, and thus less inorganic material will reach NN2; • There are great potential negative impacts to water quality from mining Water Quality E:22 ADB TA 4921-LAO: Preparing the Cumulative Impact Assessment for the Nam Ngum Hydropower Project Components A, parts and 2, Final CIA Report, Appendix E Engineering Hydrology and Hydropower activities in the basin, especially in the case of accidents with large releases of e.g tailings material; • The release of water from the NB1 reservoir will have a negative impact on thee NN1 reservoir (or NN2, depending on choice of release point); • The water quality in the NN5 reservoir is expected to still be rather poor The release of water from NN5 will affect the NN3 reservoir; • Decrease in dissolved oxygen (DO) concentrations downstream of construction areas Decreased DO could result from off site discharge of wastewater from construction camps Low DO groundwater could also be released during dewatering activities; • Increased pH and alkalinity could result from concrete/cement contamination; • Possible increased pathogen concentrations downstream of construction areas/camps; • Elevated nutrient concentrations could also result from off-site discharge of wastewater from construction camp areas Explosive residues could be another source of nutrients Excess nutrients could trigger algal blooms in the NN2 reservoir Nam Lik –Nam Xong (3) • Two years after filling, the degradation of biomass and organic matters in the NL2 reservoir is expected to continue, resulting in increased concentrations of metals and nutrients At the same time, the NL2 reservoir is expected to have a somewhat lowered dissolved oxygen concentration, particular in the lower layer of the reservoir; • The poor water quality of the outflow from the NL2 reservoir will exacerbate water quality problems in the NL1 reservoir Lower Nam Ngum (4) • The building of NL1 and NL2 will strongly affect the water quality in the low Nam Ngum River The dilution by relatively clean Nam Lik water that takes place at present will no longer be in place; • The water quality of the water discharged from NL and NN hydropower stations will permanently influence the conditions far downstream of the confluence of the two rivers Mid Nam Ngum (2) Negative Impacts • Due to evaporation from the NN2, NN3, NN5, NB1 and NB2 Reservoirs, the inflow to the NN1 Reservoir will be reduced by a cumulative total of 1.40 m3/s compared to the inflow at present situation 2007 (a further 0.24 m3/s compared to scenario 2); • Due to evaporation from the NN3 and NN5 Reservoir, the inflow to the NN2 Reservoir will be reduced by a cumulative total of 0.30 m3/s compared to the inflow according to Scenario (a further 0.10 m3/s compared to scenario 2) • NN2 will lose a total of 22 GWh of generation as a result of the filling of the NN5 reservoir while the loss at NN1 will only be GWh Positive Impacts • The wet season inflows to the NN1 and NN2 Reservoirs will be lower while the dry season inflows will be higher; • The average water levels in the reservoirs will be higher and the spillage ADB TA 4921-LAO: Preparing the Cumulative Impact Assessment for the Nam Ngum Hydropower Project Components A, parts and 2, Final CIA Report, Appendix E E:23 Land Use Irrigation E:24 will be reduced; • Despite a reduced inflow compared to scenario 2, the yearly average energy generation at NN1 will increase from approximately 068 GWh/year up to 082 GWh/year, an increase by 14 GWh/year; • Despite a reduced inflow of 0.1 m3/s to NN2, compared to Scenario 2, the yearly average energy production at NN2 will increase from approximately 871 GWh/year up to 887 GWh/year, an increase of 16 GWh/year • It will take around one a a half year for NN2 to reap net benefits from the existence of the NN5 reservoir, and less than half a year for positive impacts to be experienced at NN1 Nam Lik –Nam Xong (3) Negative impacts • Considerable areas upstream the NL1 and NL2 Dam Sites will be flooded; • Due to evaporation from the new reservoirs, the annual average flow down-stream of the NL1 dam site will be reduced by approximately 0.28 m3/s Positive impacts • Due to the new reservoirs, the average wet-season flows down-stream the NL1 dam site will decrease from about 305 m3/s to 281 m3/s, while the dryseason flows will increase from about 40 m3/s up to 74 m3/s; • The energy production in the new NL1 and NL2 plants will be 233 and 271 GWh/year respectively Lower Nam Ngum (4) Positive Impacts • Taking evaporation and irrigation into consideration, the wet-season flows in the Vientiane plains will be reduced from around 720 m3/s to 690 m3/s while the dry-season flows will increase from around 330 m3/s to 365 m3/s Upper Nam Ngum (1) Positive Aspects • Villagers retain access to about 000 of their traditional farming land Mid Nam Ngum (2) Negative Impacts • Cumulative area of almost 12 000 of upland agricultural land inundated; • Cumulative area of over 500 of paddy land areas inundated; • Some potential for shifting cultivation in areas adjacent to NN5 reservoir by fishing populations Positive Impacts • Regenerating forests will reach an area of over 10 000 Nam Lik –Nam Xong (3) Negative Impacts Impact on top of scenario 2a: • Nam Lik and inundate almost 500 of upland agricultural land and a small area of paddy land Positive Aspects Impact on top of scenario 2a: • No negative upstream impacts on upstream land use; • Substantial upland farm areas will not be affected; • Nam Tong sub-basin farm lands and paddy land will not be affected Upper Nam Ngum (1) ADB TA 4921-LAO: Preparing the Cumulative Impact Assessment for the Nam Ngum Hydropower Project Components A, parts and 2, Final CIA Report, Appendix E Aquatic Ecology • No impacts Mid Nam Ngum (2) Positive Aspects Impact on top of scenario 2a: • Nam Bak reservoirs will have no negative impacts on small scale irrigation above the dam site Nam Lik –Nam Xong (3) See scenario 2a • Villagers claim there will be no impacts on small scale irrigation below the Nam Lik reservoir Lower Nam Ngum (4) • Abundant water availability for a projected 131 000 of wet season rice, 55 000 of dry season rice and 11 000 of dry season higher value crops on Vientiane plain; • Significant yield and production increases will be obtained for wet and dry season rice • Moderate increase in area of dry season high value irrigated crops; • Rehabilitation of some permanent schemes will be undertaken and improve irrigation efficiency NNRB Negative impacts • The six hydropower reservoirs completed by 2013 will entirely change the nature of the aquatic habitats and fisheries which depend upon them for their life cycles; • Previously riverine habitats will be transformed into a series of low to moderately productive reservoirs with connecting river reaches and flows largely insufficient to maintain ecosystem services; • The species composition and populations as well as productivity will be permanently and widely affected at a moderate to serious degree; • The flow regime will be altered to the point where the flood pulse may no longer provide the trigger for longitudinal fish migrations and flood events may no longer provide the opportunity for lateral migration, habitat connectivity and nutrient recharge of mainstream rivers; • From a fisheries perspective, there are long- term, widespread and serious impacts as a result of this level of hydropower development in the NN basin Positive impacts Partially offsetting the negative impacts will be: • The reservoir productivity of a number of economically viable fish species for consumption and sale This will not compensate adequately for the loss in natural productivity or biodiversity nor provide for the equitable distribution of benefits to those originally reliant upon these resources for elements of their livelihood needs, but it will offset impacts to some extent; • If recommendations are followed, there is also an opportunity to reap mod- erate to high benefit from appropriate local-state (Co-management) of aquatic resources in addition to mitigating against a number of key negative impacts This is of course reliant upon appropriate funds being allocated alongside the professional commitment and institutional capacity to so ADB TA 4921-LAO: Preparing the Cumulative Impact Assessment for the Nam Ngum Hydropower Project Components A, parts and 2, Final CIA Report, Appendix E E:25 Upper Nam Ngum (1) • Insignificant additional impact compared to scenario 2a Mid Nam Ngum (2) Negative impacts • Habitat fragmentation of the Nam Ting tributary; • River reach on the Nam Ting downstream of the NN5 unable to sustain river ecosystem services and products due to extremely low flows; • Daily and seasonal fluctuation in flows of the Nam Ting and inflow to the NN3 and impact on reservoir fishery; • Serious impact to river fish productivity and diversity in the Nam Ting Himimyzon confluens a Mekong endemic known only from riffles and rapids of the upper Nam Ngum and according to villagers of Ban Xieng Daet now only found in the Nam Tin may be affected; • Impact on NN3 & in turn NN2 reservoir fisheries as a consequence of poor water quality from NN5; • Possible local ‘extinctions’ owing to further habitat fragmentation; • There is currently a paucity of data on the Nam Bak 1but any regulation on this river (inc NB2b in 2015) will likely have very serious consequences to mitigate against the impact of poor water quality and low flows downstream of NN2; • River Fisheries and aquatic habitats in the Nam Bak affected by changes and fluctuations in flow; • Poor water quality from the Nam Bak will impact river residents Positive impacts • Short term windfall catches on impoundment of NN5R; • Minimal benefits derived from reservoir fisheries in the NN2, NN3 and NN5 Nam Ngum Reservoir • Moderate cumulative impact on NN1R fisheries due to water quality reduction in NN3, NN2 and Nam Bak This impact is seen most prominently adjacent to Keng noi conservation area; • Spawning/migration areas especially Nam Bak negatively affected by water quality, hydrological fluctuations and migration pathway blockages Additional impacts to the already seriously threatened NN1 reservoir productivity and last remaining refuge for river species and NN1R migratory species Nam Lik Nam Xong (3) • Key migration routes from the Mekong are blocked after Nam Lik & Impact on migratory species is moderate to serious, long term and extending beyond the Nam Ngum basin to the Mekong River; • Habitat fragmentation and blockage of local and Mekong migrants; • Moderate to serious negative impact on fish productivity and diversity in the Nam Lik; • Water quality issues D/S of Nam Lik and U/S & D/S of Nam Lik affect the aquatic fauna; • Variation in flow rate and volume combined with increase sediments likely to change the benthic geomorphology particularly the deep pool immediately down stream of the Nam Lik 2; • Daily and seasonal fluctuations in flow moderate to serious impact as E:26 ADB TA 4921-LAO: Preparing the Cumulative Impact Assessment for the Nam Ngum Hydropower Project Components A, parts and 2, Final CIA Report, Appendix E Terrestrial Ecology flooding regime and pulse may be altered with consequent negative impact on lateral migrants and river productivity owing to a lack of nutrient recharge of the mainstream when flood waters recede; • Impact of increased nutrient run off from increased irrigated agriculture likely to impact aquatic fauna; • Moderate to serious impact on livelihoods due to loss of fish productivity Positive impacts • Short term windfall catches on impoundment of Nam Lik 2; • Minimal benefits derived from reservoir fisheries in the Nam Lik Lower Nam Ngum (4) • Water quality issues evident during and immediately after construction of the Nam Lik dams may create a toxic barrier to fish travelling upstream from far below the confluence of the Nam Ngum; • Minimal to moderate impact on fisheries, both short (water quality) and long (hydrology) term The entire NNRB Negative impacts • The six hydropower reservoirs completed by 2013 cover 23 000 – representing 1.3 % of the total NNRB area A third of the combined reservoir area consists of forests The forests in the reservoirs represent % of the total forest area in the whole NNRB The impact of the forest loss is minor, seen in a NNRB perspective; • All reservoirs are located away from designated NBCAs, Conservation Forests or known key habitats The impact is thus predicted as minor; • Hydropower development requires improved or new infrastructure i.a an estimated 150 km of roads and 350 km of transmission lines The impacts hereof are moderate in a river-basin perspective; • The reservoirs impede migrations routes The impacts are minor; • Limited in-migration to some of the reservoir areas implies minor impacts Positive impacts • Watershed Protection Forests and key habitats have moderate positive impacts in the whole river basin; • Resettlement has a positive effect on forests in the original location – which is abandoned – but worsens the situation in the new locality The combined impact is predicted to be slightly positive; • Watershed management interventions, awareness raising, extension support to villagers in the river basin have moderate positive impacts Lower Nam Ngum (4) • The expansion of hydro schemes implies less logging in the NNRB But since wood demand is maintained – or even increased - tree plantations are established Some plantations contribute to good forestry and enrich biodiversity – others not Nam Lik Nam Xong (3) • Nam Lik is located right in a Production Forest Systematic and multipurpose forest management can be good for the hydropower scheme but if logging is not supervised the impact can be negative Negative impacts • With Nam Lik and land and forests are taken out of production Nam Lik is in a densely forested area The impact is still minor seen in the IZ perspective; ADB TA 4921-LAO: Preparing the Cumulative Impact Assessment for the Nam Ngum Hydropower Project Components A, parts and 2, Final CIA Report, Appendix E E:27 • SocioEconomy and Poverty E:28 Resettlement at Nam Lik brings people from the river plains closer to the forested areas with more impacts on forests; • Nam Lik brings new infrastructure into an area which at present is isolated Locally this has a significant impact Mid Nam Ngum (2) Negative impacts • As per Scenario with the addition of one small reservoir – Nam Bak – and the more sizable NN5 No NBCAs or Conservation Forests are affected The impact of all four reservoirs on forests and biodiversity is moderate, seen in the IZ perspective; • The infrastructure expands somewhat as compared to Scenario Nam Bak opens up an area which is presently inaccessible This has a minor negative impacts seen in a IZ perspective Upper Nam Ngum (1) • As per Scenario Upper Nam Ngum (1) • See scenario 1a Mid Nam Ngum (2) Negative Impacts • If the socio-economic safeguards are not implemented according to ADB and other international standards, severe negative impacts can be expected for all three additional projects (NN5, NB1 and NB2), similar in nature to those described for NN2 in scenario 1a, even if the problems caused by resettlement into a host community will likely not develop in these projects • However, on the condition that planning and implementation of NN5, NB1 and NB2 have been accompanied by adequate environmental and social safeguarding activities fulfilling ADB and other relevant international standards, it is expected that no major cumulative negative impacts will have occurred (on top of scenario 2a) Positive Impacts NN2 • See scenario 1a NN5 A compensation programme has been put in place by the project, following the recommendations in the SAP (Dongsay 2006) As a result of this programme, it is expected that villagers in the affected area will have better access to: • social services (health, education); • roads and markets; • electricity; • new technologies and information; • new employment opportunities; NN3 • See scenario 1a Nam Bak 1-2 • Not enough information available for conclusive impact prediction ADB TA 4921-LAO: Preparing the Cumulative Impact Assessment for the Nam Ngum Hydropower Project Components A, parts and 2, Final CIA Report, Appendix E Health Nam Lik – Nam Xong (3) • If the socio-economic safeguards are not implemented according to ADB and other international standards, severe negative impacts can be expected for the zone, similar, but reinforced, in nature to those described for NN2 in scenario 1a The added need for land and other resources for several thousand more resettlers could, if planned poorly, cause severe negative cumulative impacts on the area, with widespread socio-economic marginalisation as a result • The eco-tourism industry on the Nam Lik is severely affected by the construction of the two dams on the river Nam Lik If mitigation programmes (RAP, SAP) have been drafted and implemented and have dealt successfully and to the contentment of the affected villagers with all issues: • Inundated houses, one school, one temple, and fields in parts of villages have been relocated and compensated; • 19 other affected villages have been compensated for their loss of assets, natural resources and loss of production; • Approximately km of a flooded rural access road has been rebuilt; • After a transitional period, affected villagers’ livelihoods are expected to be raised to pre-project levels within 3-4 years Lower Nam Ngum (4) • See scenario 1a NN2 • High impact on malaria and stress-related diseases and problems among the population and the resettled people; • Medium to high impact on ARI, malnutrition, HIV/AIDS, other STIs and traffic accidents; • Low to medium impact on drowning NN3 • Medium to high impact on HIV/AIDS, other STIs and traffic accidents; • Medium impact on malnutrition and stress-related diseases on the population; • Low to medium impact on malaria, ARI, drowning; • Potentially serious negative impacts on people’s security downstream of the plant, since no re-regulation is planned, leading to very rapid fluctuations in water flows when the turbines are turned on and off NN5 • Medium impact on HIV/AIDS and other STIs; • Low to medium impact on drowning and stress-related diseases and problems among the population; • Low impact on malaria, ARI, malnutrition and traffic accidents • Potentially serious negative impacts on people’s security downstream of the plant, if no re-regulation is implemented, leading to very rapid fluctuations in water flows when the turbines are turned on and off Nam Lik – Nam Xong (3) • Medium impact on HIV/AIDS and other STIs; • Low to medium impact on malaria, drowning and stress-related diseases ADB TA 4921-LAO: Preparing the Cumulative Impact Assessment for the Nam Ngum Hydropower Project Components A, parts and 2, Final CIA Report, Appendix E E:29 and problems among the population; • Low impact on ARI, malnutrition and traffic accidents among the resettled people • Potentially serious negative impacts on people’s security downstream of the plant, if no re-regulation is implemented, leading to very rapid fluctuations in water flows when the turbines are turned on and off Lower Nam Ngum (4) • Low to medium impact on traffic accidents E:30 ADB TA 4921-LAO: Preparing the Cumulative Impact Assessment for the Nam Ngum Hydropower Project Components A, parts and 2, Final CIA Report, Appendix E E.6 Scenario 3b, Present situation + NN2, NN3, NN5, NL1, NL2, NB1 and NB2 and 61 000 additional of pumped irrigation and 39 000 of gravity-fed irrigation in 2020 Sector Direct and Indirect Impacts Water Resources Upper Nam Ngum: (1) • We treat the NN3 reservoir under Impact Zone 2, even if it borders on two zones Mid Nam Ngum (2) • Increased evaporation from to the new reservoirs; • Large daily fluctuations in the water discharge from the power stations will have a negative impact on downstream areas; • Less water will be discharged to downstream reservoirs during the filling of new ones Nam Lik –Nam Xong (3) Fuang District Re-settlement Area: • Resettlement of villagers from the NN2-affected areas to the Fuang District and development of irrigation systems to support the livelihood of resettled villagers are likely to increase pressure on water resources, e.g diversion of water for irrigation and domestic use; • The ground water resources in this area might be affected if the high influx of new residents result in heavy use of pumped groundwater supply Other areas: • Increased evaporation from to the new reservoirs; • Large daily fluctuations in the water discharge from the NL1 and NL2 power stations will have a negative impact on the downstream areas; • Less water will be discharged to downstream areas during the filling of the NL2 reservoir Lower Nam Ngum (4) • Sediment transport in the Nam Ngum River downstream of the confluence of the Nam Ngum and Nam Lik rivers will likely have been reduced significantly; • The plan for 100 000 new of irrigation development in the Vientiane plain and the plan for water transfer between Laos and Thailand could further reduce flow in the Nam Ngum River Mid Nam Ngum (2) • Water quality will be improved for all reservoirs in the Middle Nam Ngum River zone, due to the depletion of organic materials However, thermal stratification of the reservoirs will persist, especially during the dry season The release of hypolimnion water with a lower dissolved oxygen content and cooler temperature from reservoirs, will still negatively influence water quality of downstream water bodies Nam Lik –Nam Xong (3) • Water quality in the NL1 and NL2 reservoirs will likely have been improved Organic materials which caused the increase of nutrient and metal concentrations, and depletion of dissolved oxygen after filling, will likely have been utilised Consequently, the release of nutrient-rich water from NL2 to NL1 and from NL1 to the downstream river will be reduced Water Quality ADB TA 4921-LAO: Preparing the Cumulative Impact Assessment for the Nam Ngum Hydropower Project Components A, parts and 2, Final CIA Report, Appendix E E:31 Engineering Hydrology and Hydropower Land Use Irrigation Aquatic Ecology E:32 Lower Nam Ngum (4) • The water quality of the water discharged from NL and NN hydropower stations will permanently influence the conditions far downstream of the confluence of the two rivers, but the water quality is expected to improve as compared to the situation in scenario 3a; • There will, however, be a residual negative impact on water quality See above for scenario 3a Mid Nam Ngum (2) Negative Impacts Impact on top of scenario 2b: • Some reduction in water yields from about 10 000 of regenerating forest; • Some potential for additional shifting cultivation adjacent to the NN5 reservoir by fishing populations Nam Lik –Nam Xong (3) • See scenario 3a Upper Nam Ngum (1) • No impact Mid Nam Ngum (2) Impact on top of scenario 3a: • No negative impacts on small scale irrigation schemes upstream of the reservoirs Nam Lik –Nam Xong (3) Impact on top of scenario 3a: • No impacts on small scale irrigation systems below the dam site Lower Nam Ngum (4) Difference from scenario 3a: • Abundant water availability for a projected 131 000 of wet season rice, 66 000 of dry season rice and 16 000 of dry season higher value crops on Vientiane plain; Upper Nam Ngum (1) As per Scenario 3a Mid Nam Ngum (2) Negative impacts • Severe and long-term impact to river habitat and fish productivity; • Upper Nam Ngum likely to include less migrant species and possible local extinctions; • Nam Bak no longer a key spawning area and resultant impact for Nam Bak populations; • River reach D/S of Nam Bak 2b will have low/no flows after impoundment; • Potentially serious impact on water quality and fisheries from mining, if concessions are granted Positive impacts • NN5, Nam Bak 1&2 and Nam Lik 1&2 reservoirs with minimal to moderADB TA 4921-LAO: Preparing the Cumulative Impact Assessment for the Nam Ngum Hydropower Project Components A, parts and 2, Final CIA Report, Appendix E Terrestrial Ecology SocioEconomy and Pov- ately productive fisheries Nam Ngum Reservoir • Ability of reservoir fisheries to recover from prolonged and serious impacts still in question It is likely that little local recruitment will occur especially in river fish species Expect regular stocking of exotics and cage culture with benefits less equitably distributed as it is difficult to exclude larger companies from dominating these types of fisheries Positive impacts • Water quality improvement in all connected reservoirs with resulting improvement in reservoir inflows Nam Lik Nam Xong (3) • Flood regime altered and impact on migratory and non migratory species; • Habitat fragmentation and loss of numbers of Mekong migrants; • Impact of increased nutrient run off from increased irrigated agriculture likely to impact aquatic fauna; • Considerable impact on livelihood due to loss of fish productivity and increased fishing pressure Positive impacts • Water quality stabilised; • Reservoir fisheries established and minimally productive Lower Nam Ngum (4) Negative impacts • Flood regulation and altered flow regime impacts on fisheries and aquatic habitats; • Regulation of Nam Lik causing minimal to moderate additional long term impact on fisheries; • Impact of increased nutrient run off from increased irrigated agriculture likely to impact aquatic fauna Positive impacts • Water quality stable or near stable along the Nam Ngum NNRB Positive impacts • Slight positive developments are achieved mainly due to better protection of the riparian forest; control of timber harvesting; and watershed management interventions which result in improved natural regeneration On an NNRB scale, the combined impacts are moderate Lower Nam Ngum (4) • As per Scenario 3a Nam Lik Nam Xong (3) • As per Scenario 3a Mid Nam Ngum (2) Negative impacts • As per Scenario 3a with one additional and small reservoir, Nam Bak Impact on IZ level is predicted to remain the same as 3a Upper Nam Ngum (1) • As per Scenario 3a Upper Nam Ngum (1) • See scenario 1b Mid Nam Ngum (2) ADB TA 4921-LAO: Preparing the Cumulative Impact Assessment for the Nam Ngum Hydropower Project Components A, parts and 2, Final CIA Report, Appendix E E:33 erty Health E:34 Negative impacts • See scenario 3a Positive Impacts NN2 • See scenario 1b NN5 Provided that the application of social and environmental safeguard measures has been successful, affected villagers of NN5 have reached living standards comparable or even higher to those of pre-project times; it is expected that most of them will have better access to: • social services (health, education); • roads and markets; • electricity; • new technologies and information; • new employment opportunities; NN3 • See scenario 2b Nam Bak 1-2 Not enough information available for conclusive impact prediction Nam Lik – Nam Xong (3) Negative impacts • On the condition that the implementation of safeguards have been carried out according to international standards - no unmitigated negative impacts, except on tourism, are expected at this stage – EMP activities should have been successful Positive Impacts On the condition that planning and implementation of NN2 resettlement and Nam Lik hydropower project have been accompanied by adequate environmental and social safeguarding activities, the following positive impacts can be expected: Nam Lik • Project-affected people’s livelihoods have reached pre-project levels or even better; • Project-affected people have improved social and physical infrastructure, and new employment opportunities Lower Nam Ngum (4) • See scenario 2b NN2 • High impact on malnutrition and HIV/AIDS; • Medium impact on other STIs; • Low to medium impact on TB and stress-related diseases and problems among the resettled people; • Low impact on drowning NN3 • Medium to high impact on malnutrition and HIV/AIDS; ADB TA 4921-LAO: Preparing the Cumulative Impact Assessment for the Nam Ngum Hydropower Project Components A, parts and 2, Final CIA Report, Appendix E • Medium impact on other STIs; • Low to medium impact on TB; • Low impact on drowning • Potentially serious negative impacts on people’s security downstream of the plant since no re-regulation is implemented, leading to very rapid fluctuations in water flows when the turbines are turned on and off NN5 • Medium impact on HIV/AIDS; • Low to medium impact on TB and STIs; • Low impact on malnutrition • Potentially serious negative impacts on people’s security downstream of the plant, if no re-regulation is implemented, leading to very rapid fluctuations in water flows when the turbines are turned on and off Nam Lik – Nam Xong (3) • Medium impact on HIV/AIDS; • Low to medium impact on other STIs; • Low impact on malnutrition • Potentially serious negative impacts on people’s security downstream of the plant, if no re-regulation is implemented, leading to very rapid fluctuations in water flows when the turbines are turned on and off ADB TA 4921-LAO: Preparing the Cumulative Impact Assessment for the Nam Ngum Hydropower Project Components A, parts and 2, Final CIA Report, Appendix E E:35 ... Preparing the Cumulative Impact Assessment for the Nam Ngum Hydropower Project Components A, parts and 2, Final CIA Report iii iv ADB TA 4921-LAO: Preparing the Cumulative Impact Assessment for the... Preparing the Cumulative Impact Assessment for the Nam Ngum Hydropower Project Components A, parts and 2, Final CIA Report xxiii xxiv ADB TA 4921-LAO: Preparing the Cumulative Impact Assessment for the... expected outcome To facilitate the impact assessment for the scenarios, four impact zones were identified The reason for not using the, in hydropower environmental assessments, standard approach