China - Ertan Hydroelectric Project : environmental assessment and resettlement

* EI1I1 The People's Republic of China Ertan Hydroelectric Development Corporation Ertan Hydroelectric Project Environmental Assessment and Resettlement (FINAL REPORT ) December. 1994 :---a E. .ee.-.Corvomany Intera. tional. L.? C..:^ag ;; lUSA C ne.. -, H.a.o_ie;,- r.resr.gar.on and Descign Insait. .- Chengdu. Sichuan. PM(C. Siehuan Pra incial Resettlement AgencN. Chenac1tt. ,.nmuan. PRC Ertani Hvdroelectric Development Corporadlnil. II'ihiI hua. Sichuan. PRC Chengdu. Sichuan. PR China '- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~.~~~~~~~~~~  List of Preparers: Hasa Engineering Company International, LP.: Mr. John R. Bizer, PhD, Senior Biologist Mr. Anthony Whitten, PhD, Senior Biologist Chengdu Hydroelectric Investigation and Design Institute: Mr. Shi Shuzi Deputy Hed, Planning Department, Sr. Economist Mr. Liu Zheniai Engineer in Charge, Meteorologist Mr. Y Weiqi Head, Environmental Section, Ecologist Mr. Cao Jiang - Head,Sediment Section, Sediment Specalt Mr. Chen Guochun Deputy Head, Hydrological Section, Hydro. Specialist Mr. Bai Chunfeng Senior Economist Mr. Rao Zhongli Resentement Specialist Ms. Shu Zeping Environmental Engineerng Specialist Ms. Wang Xueqin Environmental Specialist Ms. Rang Hong Envimnmental-hydraulic Specialist Mr. Liang Ruijing Interpreter Sichuan Provincial Resettlement Agency: Mr. Chen Zongyi Head, No.3 Deparment, Senior Engineer Ms. Li Hongmei Engineer, Chemist Ertan Hydroelectric Development Corporation Mr. Wang Keming Deputy Chief Engineer Mr. Cui Zijun Head, Adminitration Department, Sr. Engineer Mr. Chen Xiumei Senior Engineer Mr. Su Zhou Senior Engineer Mr. Li Renlun Head, Planning Department, Sr. Engineer  LIST OF TABLES Table 1.1: Basic Structure of Common Energy Resources in Sichuan Province (1992) 1.4 Table 1.2: Comparison of Capital Invesment and Annual Opeating Costs of a 2860 MW Thernal Plant with the 3,300 MW Ertan Project 1.5 Table .13: Esimated pollutants generated from buniung of 9.04 million Tons of coal annually at a thewral generating project 1.6 Table 1.4 Sistical Comparison of Ertan Hydroelectric Projects with Comparable Projects Throughout the World 1.8 Table 4.1: Summary of Meteorological Data Charactrzing the Climate of the Yalong River Catchment. 4.6 Table 4.2: Average and Extreme Discharges Measured at Yanbian Station on Ganyu River 4.17 Table 4.3: Industrial Water Consumption and Discharge Rates and Major Pollutants in Area of Ertan Reservoir 4.22 Table 4.4: Water quality characteristics of the Yalong River at the Xiaodeshi Gaging Station (1973-1979, 1981) 4.26 Table 4.5: Monthly Average Water Quality Values at Xiaodeshi Gauging Station in 1989 and 1990 4.29 Table 4.6: Longitudinal profile of water quality parameters in Yalong River from Gabiao to Tongzilin 4.31 Table 4.7: Summary of water quality data from Jinsha River Upstream and downstream from Yalong confluence 4.34 Table 4.8: Restricted-range birds of the broad-leaved 'South Chinese Forests' 4.53 Table 4.9: Survey of Land Uses in Yalong River Basin in Ertan Reservoir Area 4.61 Table 4.10: Trends in Forest Cover, 1960-1980 4.61 Table 4.11: Industiees Located in the Ertan Reservoir Area 4.65 Table 4.112: Socioeconomic Conditions in 1985 for the Five Counties Affected by the Reservoir 4.68  Table 5.1: Hourly Discharge from Eran Power Station during Peaking Operation in Normal, Wet and Dry Years. 5.10 Table 5.2: Schedule of Generation by Hour for Ertan Peaking Opeation. 5.11 Table 5.3: Averge Scour Depth in Yalong River downstream from Ertan Dam 5.19 ,' Table 5.4: Summary of submersion losses in Ertan Reservoir Area. 5.55 Table 5.5: Enumeration of the utilizabe area of the driwdown zone for development in the Ganyu Arm of the Ertan Reservoir. 5.58 Table 5.6: Inventory of Vegetadon, Structur and Sanitary Faciliies to be Removed as Part of Reservoir Clearance. 5.67 Table 7.1: Preliminary List of Equipment for Monitoring Program 7.10 Table 7.2: Itemized Costs for Environmental Mitigation Programs 7.16 Table 7.3: Itemized Costs for Environmental Monitoring Programs 7.18 Table 7.4: Environmental Costs and Their Year-by-Year Allocation Schedule 7.19 ;-  Eran Hydrectric Project Envirnmental Assesment and Resettlement (FNAL REPORT) TABLE OF CONTENTS- EECUTVE SUMMARY 1. INTRODUCTION - ..........................1 ............. l. 1.1. HLitory ofthe Project ............................1.._ 1.2. Justification of the Project .1.2 1.3. Analysis of Altenative Energy Sources .1.3 1.4. Comparison with Other Major Intertional Hydrodectric Projects ... 1.7 1.5. HistoryoftheEnvironmentalAssessment .1.8 1.6. Introduction to This Study ........ 1.9 2. PROJECT DESCRLPItON .................... 2.1 2.1. General Project Description ........................... 2.1 2.2. Physical Plant ........................... 2.4 2.3. Reservoir .............................. 2.10 14. Construction Methods .............................. 2.11 2.5. Project Operation .............................. 2.15 2.6. Transmission Line and Substations .... ..... ............ 2.16 2.7. Cost Summary .................................. 2.16 3. POLICY, LEGAL, AND ADMINISTRATIVE FRAMEWORK .. ....... 3.1 3.1. Environmental Protection ............................ 3.1 3.2. Resettlement .................................... 3.8 4. BASELINE CONDITIONS ................................ 4.1 4.1. Physical Geography ................................ 4.1 4.2. Biogeography .................................. 4.7 4.3. The Aquatic System ................................ 4.9 4.4. Terrestrial Vegetation, Wildlife and Biodiversitv ..... ........ 4.41 4.5. Socio-economic Environment ......... ................ 4.55 5. ENVIRONMENTAL EFFECTS .................. 5.1 5.1. Environmental Benefits ............................... 5.2 5.2. Aquatic Impacts and Mitigation ........................... 5.6 5.3. Terrestrial Impacts and Mitigation ......................5..2.., 5.4. Socio-economic Impacts and Mitigation ....... ............ 5.49 5.5. Construction Impacts and Mitigation ......... ............ 5.63 5.6. Transmission Line Effects and Mitigation ....... ........... 5.69 6. RESEITLEMENT AND SOCIAL ISSUES ...................... 6.1 6.1. National Resettlement Policies. 6.1 6.2. Characteristics of Resett!zemen: Areas .... ... ............. 6.1 6.3. Socioeconomic Profile in Areas to Be Inundated .6.4 6.4. Consultation Process ............................... 6.5 6.5. Institutional Arrangements ................. .... ..6.7  7. ENMRONMENTAL MONITORING AND TRAINING PROGRAM ...... 7.1 7.1. Overview of The Monitoring Program . .................: 7.1 7.2. TriningPgmm andSpc Activities .. 7.12 7.3. Coss .7.14 8. RECOMMENDATIONS ANNEX 1 Rferences ANNEX 2 Species List ANNEX 3 The I pl.meutation of lwfroi a.utal Protection Measures  LTSr OF FIGURES Figure 1.1: Relationship between ntal capacity and cost per kW for 49 proects in Sichuan Province.(CHIDI, 1994). 1.7 Figure 2.1: Lotion of Ertan Hydeect Prqject on Yalong River in Southwestern Sichuan. 2.2 Figure 2.2: Comprehve Development Plan for Lower Yalong River Involving 11 Hydreectric Prciects. 2.3 Figure 2.3: Layout of Ertan H ic Project Facilities. 2.5 Figure 2.4: Elevation-and Longitudinal Section thrugh Ertan Dam Depicting Dam, Spillways and Plunge Pool. 2.6 Figure 2.5: Section Through Underground Power Station for Ertan Project * Depicting Intake, Penstock, Underground Chambers, and Tailrace Tunnels. 2.9 Figure 4.1: The Chang Jiang (Yangtze) River and its tributaries, including the Yalong River Cm bold) and the locations of the Erti and Gezhouba hydroelectric projects. 4.2 Figure 4.2: Yalong River watershed within Sichuan Province: Drainage area of Ertan Hydroelectric Project. 4.3 Figure 4.3: Relief map of Yalong River Basin in Southwest Sichuan Province, China. 4.4 Figure 4.4: Locations of Known Geologic Faults in the Vicinity of Ertan Project and Locations of Seismic Monitoring Stations. 4.8 Figure 4.5: Biounits of western Sichuan. 4.10 Figure 4.6: Locations of Hydrologic. Watcr Quality and Mecteorological Monitoring Stations in the Yalong River Basin. 4.1l Figure 4.7: Average Monthly Discharge at Wali, Luning and Xiaodeshi Hydrologic Gauging Stations on Yalong River. 4. I^ Figure 4.8: Flow Regime Representing High Flow Year in Yalong River (Measured at Xiaodeshi Gaging Station). 4.13 Figure 4.9: Flow Reginie Representing a Normal Year in Yalong River (Measured at Xiaodeshi Gaging Station). 4.14  Figure 4.10: Flow Reime Representira Low Flow Conditions in Yalong River (Measured at Xiaodeshi Gaging Station). 4.15 Figure 4.11: Average monthly flow in Ganyi River (Yanbian Gauging Station, 1976-1993). - 4.16 Figure 4.12: Relative average monthly discharge of Yalong and JIrsha River downstream from confluence. 4.18 Figure 4.13: Monthly aveage wa temperate of Yalong River at Xiaodeshi. Gaging Station (1959 - 1992) 4.24 Figure 4.14: Monthly water temperature regime of Ganyu River at Yanbian Gaging Station (1978 . 1982) 4.25 Figure 4.15: Distributions of Three Fish Species Found irn Project Area Representing the Three Major Distribution/Ecological Types: Type A = plains; Type B = Mid-Elevaion; and Type C = High - Elevation. 4.37 Figure 4.16: Photograph of Fish Species Observed in Fishermen's Catch at Mouth of Puwei River on May 28, 1994. 4.39 Figure 4.17: Forestry map (1978) of the lower Yaldng watershed and surroundings. 4.42 Fi-ure 4.18: Distribution of mature forests in the lower Yalong basin in 1985. 4.43 Figure 4.19: Open, savannah-type vegetation characteristic of the steep slopes of the valley walls within the Ertan Reservoir area. 4.44 Fivure -.'0 Schematic representation of altitudinal zones of vegetation in the Yalong Vallev. 4.45 Fiiurv :.': Current. Known Distribution of Giant Pandas in Western Sichuan (narrow lines; and Locations of Nature Reserves (bold-gazetted. hatched-propus.d) (Sichuan Forstry Department, 1985). 4.50 11-ure. .' Locations of Reserves in the Southwest Mountains Biounit in Sichuan PTnvince: B12-a - gazetted; white - proposed 4.54 Figure 4.23: Locations of Timber Harvest Areas and Forest Management Bureaus in Yalong Rlver Basin. 4.58 Figure 4.24: Log Handling F=Iii._s in Y' aong River at Xiaokesh.1 1! km Downstream Fru::, Eix. 4.59 Figuzv 4.25: Adrministrati;e ;Thts ir l'L E-rmn Reservoir Area. 4.67  '0 ' 2 ' '; ~. '', '.0 ' '- . .s.''', -; ', -'t- * Figure 4.26: Yi Woman Herding Goats. 4.70 Figure 4.27: Distribution of Schistosomiasis Disease Vectors in Yanbiars County (Panzhihua Health Bureau, 1993). 4.74 Figure 5.1: Representative Water Levels in the Ertan Reservoir through Five Yea=s of Opwation (Based on the 1961-1965 Flow Regimes). 5.8 - Figur 5.2: Effet of Daily Flow Fluctuation at Six Locations Downstream froip Ertan Dwa. - 5.12 Figure 5.3: Longitudinal Profile of Sediment Accumulation in Ertan Reservoir 5.15 Figure 5.4: Longitudinal Profile of Sediment Accumulation in Ganyu Arm of Ertan Reservoir 5.16 Figure 5.5: Locations of proposed fish harvest facilities on Ertan Reservoir and Ganyu Arm. 5.39 Figure 5.6: Schematic diagram of trammel and trap net deployment for fish harvest. 5.40 Figure 5.7: Distribution of Drawdown Areas for Development in the Ganyu * Arm. 5.57 Figure 6.1: The Hongge Resettlement Area. 6.3 Figure 7.1: Administrative framework for Ertan Environmental Monitorin, Programn 7.13  Chapter 1 1. INTRODUCTION 1.1. History of the Project The hydropower potential of the lower Yalong River was recognized in the early 1950s, but detailed geological investigations did not begin until 1973. In 1980, a wide range of studies was initiated by Sichuan Provincial authorities to assess the feasibility of a hydroelectric dam at Ertan, near the mouth of the Yalong, and in early 1984 a feasibility report was submitted to the State Planning Commission. One response to the report was that it was necessary to undertake detailed planning for the resettlernent of people whose homes and lands were to be inundated. The World Bank was approached by the Chinese government in 1987 with a view to solicit a loan for the project. and in May 1988, a Pre-Appraisal Mission was conducted by Bank- staff. This mission provided to the Govemment of China guidelines and suggestions for further studies necessary for satisfactory appraisal. The Bank Appraisal Mission was conducted in December 1988. and their report was completed in March 1990. The report was approved by the Government of China in April. In July 1991. the Executive Board of the World Bank approved a first-phase loan of S380 million, and two months later the construction contractors began moving to the site to initiate construction activities. In Julv 1993. the World Bank and the Ertan Hydroelectric Development Corporatlon (EHDC) opened discussions on the second-phase loan of S500 million. The World Bank Pre-Appraisal Mission for the second-phase loan was conducted in April 1994, and the Appraisal Mission is scheduled for October 1994. tAc FA 1.1  In November 1993, the Yalong River was successfully diverted into the two diversion tunnels. The first electricity is expected to be generated in mid-1997, and the project completed in mid-1999. 1.2. Justification of the Project Sichuan Provir.-e is very rich in hydro power resources and relatively poor in other energy resources, but is severely lacking in geneadng capacity. In 1985, the total installed generating capaity in Sichuan was 2,880 MW (including both coal-fired thermal stations and hydropower stations) providing a firm capacity of 1,500 - 1,600 MW. Demand for energy was estimated at approximately 2,000 MW during the dry season each year. Provincial planning for additional industry in Sichuan revealed that by 1995, a maximum system demand of 6,500 MW and by the year 2000, the system demand is expected to reach 11,000 MW. To meet these demands, an installed generating capacity of 9,500 MW would be needed by 1995, and 14,000 MW would be needed by the year 2000. In a report prepared by the Chengdu Hydroelectric Investigation and Design Institute (CHIDI) in 1994, these estimates were updated by the CHIDI. According to the report, the demand for electricitv reached 6,900 MW (42,070 CWh) in 1992 and Sichuan Province experienced an energy shortage of approximately 7,000 GWh. Since 1985. the total installed generating capacity in Sichuan increased to 9,545 MW of which 4.089 MW is derived from hydropower projects and 5.476 is derived from thermal (coal-fired) plants. Total vield from the hydroelectric projects was 21,940 GWh while thermal plants produces only '0.5 13 G.'h for a total energy production of 41.940 GWh in 1992. Between 1992- and the year '020. the demand for power is expected to increase nearly 10-fold from 6.900 MW to 6_.000 MIW with an estimated generating requirement of over 340,000 GWh. Confronted with these projections, the need to develop additional sources of electric energy is critical to continued economic growth in the Province of Sichuan. During preliminary studies leading to the selection of the Ertan Dam, the total energy potential of the Yalong River was estimated at over 20,000 MW. Development of potential 112 1.2  generating capaity in the Yalong Basin, therefore, became a prime altenative for meeting the growng demand for power in Sichuan Province. Preliminary studies of the development of hydropower resources in the Yalong Basin were conducted by CHIDI. Results of these studies indicaed that Xte hydropower resources of the Yalong River could be developed in two phases. The fis phase will consist of the construction of 11 projects in the lower Yalong River. The second phase will complete the development of the hydroelectric resources in the basin and will indude an additional 10 projects upstream from the first phase dams. Based on the results of this study, the Ertan Hydroeectric Project was selected as the first of the 11 phase one projects to be constructed. The Ertan Pmject is designed to contribute 3,300 MW of installed generating capacity, and more than 1,000 MW of firm capacity, to the Sichuan electric distribution system. In addition to the direct contribution of over 1,000 MW of firm capacity to the Sichuan Power System, the regulation of the river resulting from the Ertan Project will increase the system-wide finn capacity by 142 MW at the Gezhouba Hydroelectric Project and by 230 MW at the (planned) Three Gorges Project on the Yangatze River in western Hubei Province and eastern Sichuan Province, respectively. This increase in firm capacity is derived primarily from the increase flow during the dry months attributable to the limited storage capacity in tile Ertan Reservoir. 1.3. Analvsis of Alternative Energy Sources The provincial government decision to pursue hydroelectric development in Sichuan Province was based on a comprehensive analysis of available energy resources within the province and an economic analvsis to find the most efficient source of energy to meet the growing demand for power as Sichuan develops into the modern world. These analyses focused on available energy resources in Sichuan Province: water, coal, gas, and oil. Additionally, the economic benefits of constructing fewer large scale projects vs many small projects was evaluated. Results of these analyses are presented in a report prepared by CHDI ir. 1994 and are briefly summarized below. SL1_2 ERA A CHIi 1.3  Table 1.1: Basic Structure of Common Energy Resources in Sichuan Province (1992) Exploimable Processed Coal Percent of Fner3y Sn,irt". Rpervec Fptivalent TWA1 (Mt) Water Power 515,291x100 (year) 22364 75.6 GWh Coal 9,591 Mt 6848 23.3 Gas 181,787-Mm3 224 0.8 oil Negligible - - Total 29436 100 As shown in Table 1. 1, potential water power developments comprise over 75 percent of the available energy reserves in Sichuan Province with available coal reserves accounting for less than 25 percent of the exploitable energy resources. In direct comparison, continued development of coal resources to generate electricity would ultimately lead a requirement for importing coal from outside the province. As a matter of Provincial policy, available natural gas reserves are targeted for industrial and domestic use (displacing urban coal use) rather than for the generation of electric power. Therefore, from this perspective alone, the decision to pursue development of hydropower resources to meet the growing energy shortage in Sichuan Province appears to be a highly desirable alternative. From an economic standpoint. development of hvdropower resources appears to be the most viable alternative for Sichuan Province. This economic factor is illustrated bv direct comparison of the estimated costs for the 3,300 MW Ertan Project with those for a 2860 MW coal-fired thermal project. each project providing a firm generating capacity of apprcxinately 1.000 %IW. The capital and operating costs for these two energy sources are summarized in Table 1.2. All costs estimated are based on the value of the Chinese yuan in 1991 (5.45 RMB M = Sl.00 US). Clearly the initial capital investment required to construct either of these two projects favors a coal fired generating facility. However, this advantage decreases markedly once the projects begin generating. A quick calculation indicates that the economic difference between a coal-fired plant and the Ertan Project 31 12 1.4 FrTAN EA CHI14  disappears within 5 years of operation. The difference between the capital costs is 3,350 x 106 fi whereas costs for .5ve years of hydro operation are 3,685 x 106 V. Over 20 years of operation (the approximate expected life of a coal-fired project) the total costs (capital and operating expenses in 1991 RMB V) clearly favors the hydroelectric project with an estimated cost savings of over 18 billion RMB ' (this difference does not account for financing or escalation costs). Table 1.2: Comparison of Capital InVestment and Annual Operating Costs of a 2860 MW Thermal Plant with the 3,300 MW Ertan Project Coal Plant Ertan Hydro Component (Million !) (Million M) Investment (Capital) Construction Cost 7.150 10.500 (including environmental cost) Operating Costs (Annual) Maintenance/Repair 257 420 Fuel 1.176 -- Transmission 214 315 Total Annual Costs 1.647 735 From an overall environmental perspective, the selection of hydropower generation over coal-. fired thermal generation becomes even more obvious. Water is a renewable resource is in abundant supply. Coal. on the other hand, is a finite, non-renewable resource. From a purely physical-presence perspective, hydropower clearly requires commitment of relatively large tracts of land resources. However. once a hydropower project is constructed. the impoundment can be exploited to provide additional benefits to the project (in the form of fisheries, transportation, recreation, and water supply). Establishment of effective environmental safeguards and implementation of appropriate resource management techniques (in compliance with national regulations and policies) can prowide considerable opporturity to preserve and restore natural and cultural resources within a buffer zone around the impoundment. In contrast, while a coal-fired plant will occupy a smaller land area for the physical plant, additional land resources must be committed to mines, mining wastes. r411r _I aTAN LA Ch * i.5  transport, and ash disposal. In addition, burning of coal contributes significandy to air pollution in the form of particulates, carbon dioxide, sulfur dioxide, nitrogen compounds and benzo [a] pyrene. Annual producdon of these byproducts of coal are summarized in Table 1.3. Efforts to control disperal of ftese pollutants into the environment is costly and not necessarily effective. Construction of a single large project, such as Ertan, also provides an economy of scale relative to the construction of a number of smaller projects. The relationship between the capital investment and size of a hydroelctric project is depicted in Figure 1.1. Data used for this figure are derived from design and feasibility studies of 49 hydroelectric projects at various stages of development in Sichuan Province. Table 1.3: Estimated pollutants generated from burning of 9.04 million Tons of coal annually at a thermal generang project Annual Production PoDlutants (Tons) Residue and Ash 1.416 X 106 Dust and Suspended Particulates 0.105 X 106 Carbon Monoxide 1,421.2 Carbon Dioxide 25.4 X 106 Sulfur compounds D.214 X 106 Nitrogen Compounds 0.08 X 106 Benzo [a] Pyrene 2,289 kIg 1.4. Comparison with Other Major International Hydroelectric Projects "112 EWM FA CHI 1.6  7000 eee. A _v A A~~~~ 2600 100 0 1.00 2000 3000 4000 5000 XInatalL.d Capacity CM4) Figure 1.1: Relationship between installed capacity and cost per kW for 49 projects in Sichuan Province.(CHIDI, 1994) At a maximum generating capacity of 3,300 MW, the Ertan Hydr--Ietric Project ranks as one of the major hydroelectric projects in the world in terms of instaled generating capacity. In comparison with other world-class hydroelectric project, Ertan is at the top in relation to the least area inundated per MW and fewest number of human displacements (oustees) per MW. A summary of available information for other projects throughout the world is presented in Table 1.4. "d1121. ERTA FA CHI 1,7  Table 14 Statistical Comparison of Ertan Hydrelectric Project with Comparable Projects Throughout the World. .Name of dma O lnE KW Q) bhul e KIClmatINe KWlh NOW Three Gorses Chum 1.000.00 13.000 110,0 0.1 13 .118 planmng haipu Brazil 12.600 13S.000 93 Pay Tucumi Brzil 30.000 7,600 243.000 1.1 233 31 1933 BabBqu razil 6,600 _ 600,000 I - Gun Veneuel 6.000 32S.000 1l Lauia Chin 73n,0 5.400 37.000 0.5 74 148 eanltio law 1990s? Chandin Fas C 5,225 5,000 8 Paulo Alibuso I-IV B' 'i1 3.914 1600 2490 ERTAN .Y cum 35,010 3300 10.100 0.3 94 326 cmpltio late 1990 Jinping Sge l-Y China 5769 3,000 9.500 1.6 .520 315 plamwed Aswan High Egpt 120.000 2.100 400.000 3.3 17 5 completed 1970 Xiaolanedi Chins 171.000 1.300 27.200 0.2 la 66 compltion mid 1990s Jiqping Stage 2-Y China 0 3.200 160 am c 0.000 planed Gundoi-Y China I80 1.600 8.189 planned Kauiba Zamnbia 57.000 1.500 510.000 8.9 26 3 1959 Zimbabwe AkosombolVoka Ghana 80.000 333 S41t'00 10.6 10 0.9 completed 1965 Piluemhe Chile 500 400 12SO Toneilin-Y China 41 440 6 0.15 10.731 n.3ao completion late 1990s Anmu Nepa 401 43 9325 Kibansi Tananis 153 30 5100 Owen Falls Uganda 0 150 1* em c a apchirs Maawi 125 200 625 Sobradinho zazlI 55.000 1050 421.400 7.7 19 2 completed 1981 Shuskou I & U Chim 67.000 1500 22 completed 1990 Yafynesa Praguay/ 50.000 8.000 160.000 3.2 160 50 completion aid 1990s * The hedwateir for the Owen Fals Pojcct is LAc Victtma. 1.5. History of the Environmental Assessment Studies to support the environmental impacts assessment (EA) of the Ertan Hvdroelectric Proiect began in 1980 concurrent with other feasibility studies. Most of the investigations and literature searches were conducted between 1980 and 1985 by the CHIDI. in cooperation with relevant scientific institutes. professional universities and colleges. The draft of the EA met stautory requirements and was submitted to the National Environmental Protection Agency in August 1985. In March 1986, the report was reviewed by a group of 78 domestic experts, engineers, and environmental administrators at the invitation of the Construction Committee of Sichuan Province. This group agreed with the conclusions of the EA, and 9%EA0 1.8  recognized the huge economic benefits of the project, the physical appropriateness of the site, the lack of sepage, the economic potentials, and the lack of additional threats to endangered wildlife. The full text of the EA was translated into English for the use during the World Bank Appaisal Mission in May 1988. 1.6. Introduction to this Study - _ The 1989 version of the Ertan Environmental Assessment (EA) was reviewed during the Pre-Appraisal mission of the Worfd- Bank for the second phase loan in April 1994. The World Bank concluded -that, since global standards for such reports had been raised substantially during the previous decade, it was necessary to review the information and revisE the conclusions contained in the 1989 report to comply more closely with present requirements of the World Bank. In parallel with the preparation of this document and preparation for the World Bank Appraisal Mission in October 1994, an environmental assessment of the transmission line system to distribute power generated at Ertan was prepared by the Sichuan Electric Power Association to support a request for funding from the World Bank to construct the facilities. The Transniissiora Line EA is presented separately (SEPA. 1994). Consequently, the environmental impacts associated with the transmission line are not addressed in the main body of this EA and the reader is referred to the Transmission Line EA for discussion of the anticipated impact. The information contained in this document addresses the environment. potential impacts and mitigation measures associated with the construction and operation of the Ertan Dam and Hydroelectric Facilities. A summary of the Resettlement Action Plan is also provided within the text of this document. The revised, detailed Resettlement Action Plan is presented as a separate document in support of the application for the second phase loan from the World Bank. EnA2 EA CHI 1.9  To accomplish the revision and update of cne Ertn Environmental Assessment, EHDC contracted with Ham Engineering International, LP (USA) for two environmental specialiss (Drs John R. Bizer, Harza; and Anthony Whitten, Diversity Matters) to work with EHDC, CHIDI, and Sichuan Provincial Resetlement Agency personnel. The draft EA was reviewed by EHDC, CHIDI and was given a preliminary review by the World Bank. Comments of these groups were incorporated into this final document by Dr. Bizer, who completed the document in September1994. 6112 RTfAN EA CAI 1.10  Chapter 2 2. PROJECT DESCRIPTION 2.1. General Project Description Ertan Hydroelectric Project is located in Panzhihua Municipality on the lower reaches of the Yalong River in south-western Sichuan Province (Figure 2.1). It is a comprehensive development with power generation as its primary objective. It is planned to be the penultimate dam in a cascade of eleven dams along the Yalong River (Figure 2.2). These damns comprise the first stage in the development of hydro resources of the Yalong River. Ultimately, ten additional sites in the upper Yalong have also been identified and may be developed as part of a second stage deveopment program. When aU of the 21 sites are developed, the total installed capacity in the Yalong River Basin will be 22,650 MW. Construction of Ertan is expected to tak-e ten years from the start of construction to the commissioning of the first of six power units in 1998. T'he Ertan project will supply electricity to the Sichuan and Yunnan power systems via a 500 kIV transmission line system currently under design and construction (see SEPA 1994 for EA and project description). The system will provide energy to load centers in Zigong, Chengdu, Yibin Xichang, Chongquin. and numerous smaller load centers along the transmission corridors. Panzhihua and Xichang will also be supplied with electricity for the smelting of vanadium and titanium. The Yalong River is a lar=e tributarv of the linsha River, which rises in Yushu Countv of Qinrhai Province. From its origin. the river generally flows southward as it passes through the western portion of Sichuan to its confluence with the Jinsha River near Panzhihua City. The Yalong valley is at the eastern extreme of the Himalayan Range. The geology and topography of this anrea is characteristic of very young mountain ranges in geological terms .vith geologic folding and movement continuing. The geology of the valley is varied, comprised of old Permian basalt, younger intrusive granites. and young sedimentary marl and shale. The total length of the Yalong River mainstem is 1500 km, with a total catchment MAJN E Ca 2.1  YANYUAN - G ' ^ yYA~NBIANs,> gMYI PA.N'HIHUA | Figure 2. 1: Location of Ertan Hydroelezri.- Project on Yalong, River in Southwestern Sichuan. 'AiNYE ANCIC Y2..  a " Figuire 2.2: Coiiiprelhensive Development Plan for Lower Yalong River Involving 11 HJydroelectric Projects 0 10 z I -,9 VIF 4~~~~4 ~~~Tongzilin 700 600 500 400 300 -32'00 100 0 DISTANCE (kin)  area of 130,000 Icn2 - somewhat larger Ohan New York State in the US, slightly smaller than Nepal, and more than half the area of Great Britain. The catchment area comprises 27.5 percent of the Jinsha catchment. The mean flow at the mouth of the Yalong River is 1800 m3/sec, and the mean runoff is 56.8 x 109 m3. The length of the river above the Ertan damsite is about 1470 km and encompasses some 90 percent of the catchment. The power station is just over 40 km from Panzhihua City and 18 km upstream from Tongzilin Station on the Chengdu-Kunming Railway line. 2.2. Physical Plant 2.2.1. Dam and Spillway The dam area is located in a 1 km-long gorge between the Jinlong and Zhongtan Streams on the lower Yalong River (Figure 2.3). The valley is V-shaped with left and right bank- slopes of 25-40a and 30W450 respectively. The Ertan damsite is characterized by a narrow river channel with a high discharge. The bedrock within the dam site is composed of Permian basalt. svenite intruding into basalt. and altered basalt formed bv the intrusion. The dam will be a double curvature arch dam with a maximum heiaht of 240 m, and a maximum static height of 188 m. The dam will impound a reservoir that will extend approximately 143 km upstream from the dam site, have a surface area of 10.100 ha. and a normal maximum operating level of 1200 m above mean sea level. The dam is equipped with four sets of spillway structures to facilitate release or excess discharge and to enable evacuation of the reservoir under emergency conditions (Figure 2.4- Three of the spillways are integral with the dam. The upper spillway, with crest elevation at 1188.5 m. consists of 7 gates each with a hydraulic capacity of 900 m3/s. 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-j aft 411  a I~W I ~~~~~~~~~~~02 WI~~~~~~~~~~~~~~~~~~~~~~~~~~~I 04 2. jLaaz~~~~~~~~~~~~~~~~~~ Fiur 24 Fevtinan Lngiudna Sponthog~EranDm epctn Dm,Splwas n Plunge Pool.~~~~~~~~~~~~~~~~~~~~~~~I sar- ~ ~ ~ ~ ~ t OMAN FA OC 2S' .6  water falls into the plunge pool at the base of the dam. The third set of spillway gates in the dam consists of 4 gates with crest elevations at elevation 1080 m. The fourth spillway consists of two, low-level tunnels, each with crest elevations of 1165 m. The hydraulic capacity of each tunnel is 3400 m31s. The two tunnels may be operated independendy or in coordination with the upper and mid-level spillways to facilit rapid evacuation of the reservoir in emergency situations. The tunnel spillways will discharge to the Yalong River approximately 800 m and 1200 m downstream from the dam, respectively. Water discharged from the upper and mid-level spillway structures will faUl in to a plunge pool area at the base of the dam. The plunge pool will be founded on bedrock and lined with concrete. A low dam, approximately 300 m downstream from the base of the dam will control the water elevation in the plunge pool. The crest of the plunge pool dam is at 1012 m. With the bottom of the plunge pool area at 980 m elevation, the total water depth maintained in the plunge pool will be 32 m. 2.2.2. Powerhouse and Switchgear An underground powerhouse with six turbine/generator units will be constructed. Each unit will have a hydraulic capacity of 277 m3/sec and an installed generating capacity of 550 MIW. The total hydraulic capacity will be 1660 m31s and the installed generating capacity will be 3300 MW. The firm generating capacity will be 1000 MW. The six rurbincfgenerator units will be conmined in an underground cavem measuring 296.24 M X 31.' m X 71 m. Each unit will be served by a 9 m diameter penstock. The centerline of the intake for the penstocks will be at elevation 1132.5 m. The 6 draft tubes will discharge water into a 94 m X 19.5 m X 70 m surge chamber which will-then direct the water into two tailrace tunnels one 16.5 m in diameter and the other 23 m in diameLer. The two tailrace tunnels will return water to the Yalong River channel approximately 800 m downstream fro;n the base of the dam. Figure 2.5 presents a section through the intake, powerhouse and tailrace of the Eran Power Station. ErrAN EWCW- 2.7  tl; g ,,z,}s1