Electrical industry of burma/myanmar
Appendix 10 KINDA DAM FIFTEEN YEARS ON: AN EVALUATION OF HYDROPOWER IMPACTS
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- Table 7.1 Kinda Dam Mulit-purpose Fact Sheet Project Objectives Turbine
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- Penstock Project Reports 39
- Annual Inflow, Release, Maximum and Minimum Water Level and Energy Generation, Kinda Dam.
Appendix 10 KINDA DAM FIFTEEN YEARS ON: AN EVALUATION OF HYDROPOWER IMPACTS Asian Development Bank, “Case Study 6: Kinda Dam Multi-Purpose Project” in Strategic Environmental Framework (SEF) for the Greater Mekong Subregion: Integrating Development and Environment in the Transport and Water Resource Sectors: Volume IV: SEF Case Study Reports, pp 119-39, March 2002. [document, pp 130-50]
Primary Objective: Economic Growth Type: Francis Secondary Objectives: Capacity Hydro-electric generation Speed: 250 rpm Irrigation No. of units: 2 Flood control Site Location Generator Mandalay Division, Myinttha township Capacity: 2 x 28 MW 65 Km South of Mandalay Annual energy: 165 Gwh
Catchment area rainfall: 1060 mm Size: 29’-6” x 34’ x 4” with shutter Irrigable area rainfall: 810 mm Conduit Catchment area (dams site): 2240 km2 Length: 465 m Catchment area (weir site): 2445 km2 Maximum discharge: 114 m3 /sec Mean annual inflow: 1.399mm3 (1950-77) Size: diameter 7.4 m Dam Service Area Type of dam: Rockfill dam Irrigable area: 175000 acres Dam height: 72 m Crop area: 201,381 acres (1994-95) Crest elevation: RL 213.36 m Crest length: 625 m Implementation Period Crest width: 10 m Project start: 1981-82 Storage volume (MOL): 970 mm3 Project completion: 1989-90 Active storage volume: 764 mm3 Maximum operating level: RL 207.25 m Project Financing Minimum operating level: RL 175.5 m World Bank loan: US $90 million Diversion tunnels: 1 Total Project Cost: US $ 270 million Length: 465 m including in foreign Diameter: 7.8 m exchange of US$156M
Length: 2 x 30 m Staff Appraisal Report (SAR) 1980 Diameter: 3.2 m Project Completion Report (PCR) 1992 Operations Evaluation Impact study 1996 Power House Type: Shaft powerhouse ------------------------------------------------- The first investigation of the dam site was undertaken during 1967-71 by the Irrigation Dept of Myanmar. In 1975, Engineering Consultants Inc.(USA) was commissioned to prepare a feasibility report, which was subsequently appraised by the IDA in May-June 1976. Additional IDA-financed engineering studies were carried out by Lahmeyer International (Federal Republic of Germany). A Staff Appraisal Report (SAR) was submitted to the IDA in May 1980. Kinda Dam was constructed with the objective of exploiting irrigation releases by producing hydro-electric energy prior to conveying and supplying an irrigated command area. Reservoir operation studies were undertaken assuming a maximum operating level of 207.26 m asl and minimum operating level of 178.61m asl. Reservoir releases were designed primarily to correspond to irrigation demand. The project was designed to generate a maximum capacity of 56 MW (two units of 28 MW each), and an average annual energy production of approximately 165 GWh. The Kinda reservoir was formed by a 71.93-metre-high rockfill dam on the Panlaung River. Water is released from the reservoir through the hydro-electric plant. Storage at the maximum operating level is 969.5 MM3 and the active storage is 763.2 MM3. The existing Kinda weir was rebuilt as a regulating dam with 2.2 MM3 of storage. The first release of water from the reservoir took place in August 1985, and power reached the national grid on schedule in January 1986. The irrigation component of the project was delayed and completed in 1991, over four years behind schedule. Before the construction of the Kinda Dam the existing Panlaung irrigation system, which included three diversion weirs on the Panlaung river, irrigated about 35,600 ha. The Kinda Dam improved agricultural production on the existing 35,600 ha and was planned to bring an additional 43,300 ha of rainfed area, predominantly bushland, under irrigation (this is less than was initially estimated to be irrigated in the original Staff Appraisal Report carried out in 1980. The combined planned irrigated area was 78,900 ha. Runoff from the catchment area upstream from the dam site is quite variable and predominantly occurs during the monsoon season. Over the 1950-77 period annual runoff varied from a minimum of about 965 MM3 (1972) to maximum of 2,400 MM3 (1956), with an annual average of about 1,400 MM3. [But} from 1986 through to 1998 the average inflow was [only] about 1,110 MM3, or approximately 76 percent of the 1950-77 average. Due to the below average rainfall in the catchment during this period (1986-98), the average release was about 1,056 MM3, again roughly 76 percent of the planned average irrigation; thus the actual irrigated area is closer to 70,800 ha. During these years hydropower production was given priority in the winter months, when the demand for irrigation was less than the water released. This contributed to water shortage during periods of higher irrigation demand. Due to head variations the Kinda Dam energy generation has varied significantly over its life. Since commissioning in 1986 the power station has generated on average 106.1 Gwh annually, which is far below the annual targeted production of 165 GWh. There has been only two years, 1992 and 1993, when annual energy production has exceeded the target of 165 GWh (Table 7.3). Table 7.3 Annual Inflow, Release, Maximum and Minimum Water Level and Energy Generation, Kinda Dam. p 125 = doc p 136
Due to study constraints, little can be said in detail about key environmental issues often associated with dams, such as impacts on fisheries and biodiversity, habitat loss, area flooded by the reservoir, downstream hydrological and geomorphological changes, and reductions in water quality; or the impacts associated with dam construction and the construction and operation of associated roads and transmission lines. It seems unlikely that a fish species inventory was carried out in the project impact area during the dam planning and design phases, or that the possible impacts of the project were identified. According to a report issued by National Commission for Environmental Affairs (NCEA) of the Myanmar Government in 1999, the growth, spread and persistence of aquatic weeds in the newly irrigated project area is the most serious environmental problem in the scheme. The report also states that poor drainage in the canal system, combined with a pattern of cropping requiring large amounts of water, has resulted in extensive water logging and salinization. The drainage problems are a result of “inappropriate design and planning of project”. A water quality monitoring program has been carried out continuously since the formation of the reservoir (NCEA, 1999). The purpose of this programme is most likely to assess the quality of the irrigation water supply and also to monitor water quality with regard to the hydroelectric powerhouse, but is also useful for fish culture management. Oxygen content and other parameters are monitored. Water quality is reported as being good, and no conditions have been observed so far which would inhibit fish development. However, it is not clear if the water quality monitoring programme is confined to reservoir water or if it also includes sampling of dam discharge water. The dam wall is 72 m high and the turbines installed are of the high head Francis type. Drawdown is substantial at 28.65 m. It is therefore possible that deoxygenation of the hypolimnion occurs annual during the dry season. This suggests that water low in oxygen (and possibly containing toxic hydrogensulphide) is discharged downstream for part of the year. A negative impact on downstream fisheries and fish biodiversity could be expected under such conditions. According to NCEA (1999) deforestation has become an issue in the project area, arising from shifting cultivation in the upper parts of the area and heavy fuelwood consumption in the lower parts. In response UNDP and the Government of Myanmar established in 1997 the project “Pilot Watershed Management for Kinda Dam”. The NCEA (1999) reports that these programmes successfully introduced watershed management technologies “appropriate” for Myanmar. Since the idea of watershed management was new to the staff of the Forest Department and to the rural people living in the catchments, it was decided first to start with a pilot project. A 24,300 ha demonstration area was selected for the pilot project in the 222,600 ha watershed area near Ywangan township in Shan State. The Food and Agriculture Organisation of the United Nations (FAO) was designated as the executing agency and Myanmar Forest Dept as the counterpart agency responsible for project implementation. The UNDP contribution was US$3.3 million and the Government contribution was K20.2 million. A pilot demonstration area was established, including multipurpose nurseries, species trials, and small scale planting. A total of about 90 miles of roadside plantations were established. Woodlots belonging to the Forest Department were established on approximately 320 ha in six village tracts in the project demonstration area. To protect the plantations, a fire protection plan was developed and 50 village guards appointed following a brief training season. According to NCEA (1999), the project resulted in almost “negligible” resettlement of persons displaced from the reservoir area. However, the construction of the dam entailed the flooding of 4 villages with a total of 96 households (426 person), as well as 29 ha of irrigated paddy and about 113 ha of rainfed cropland. The ratio of displaced persons to the power generation (which according to Goodland, 1997, is a reliable "first” approximation to distinguish between “better” and “worse dams”) is approximately 7.6 displaced persons/MW, which, while much lower than the ongoing Three Gorges Dam (71 displaced persons/MW) or the Akosombo/Volta Dam in Ghana (96 displaced persons/MW), is on the same order as the controversial Nam Theun 2 Dam in Lao PDR (8 displaced persons/MW) and the Ertan Dam in China (9 displaced persons/MW). The project is said to have provided for the resettlement of these peoples, including compensation of loss for immovable private and communal property and a subsistence allowance for about 6 months. Each family was provided an approximately 15m x 30m residential plot and a new house. The agricultural land given per family was 0.8 to 2 ha depending on the number of family members. No information is available indicating if, during the planning and development, a public consultation and stakeholder dialogue process was undertaken. NCEA (1999) notes that in the past a “top-down” planning approach had been widely used in Myanmar development programmes that concerned local peoples, with minimal success, if any, and without active participation of the stakeholders. It is further noted that under the previously mentioned “Pilot Watershed Management for the Kinda Dam” project, a “bottom-up” approach was introduced, including direct people's participation in initial planning, implementation, and maintenance, and this has proven to be a successful mechanism for motivating communities and farmers to improve land-use practices. According to NCEA (1999), initiatives such as the species trials and the small scale planting demonstrated in the pilot watershed areas have heightened awareness on the part of the government and local communities on the need for immediate action to reverse the trends in environmental degradation in the area. Expansion to a full-scale integrated watershed management program is envisaged in this area during subsequent phases of the watershed management technical assistance programme. Of particular note in evaluating the environmental sustainability of the project is the fact that production of paddy is [only] 40pc of the projection made in the initial staff appraisal report. One of the reasons offered for this in the NCEA report (1999) is that most farmers had pursued different cropping patterns after initially agreeing to plant paddy "in support of government's rice export campaign”. A World Bank OED study on agro-economic impacts of investments in gravity-fed irrigation schemes in the paddy lands of south-east Asia (1997), which included the Kinda Dam, found that that the area supplied by the irrigation system is usually considerably less than planned, and in general noted that amongst the six sites studied reasons included over-optimism, engineering errors, lower than normal rainfall, and failures to extend the tertiary canals. More significantly, the report concludes that smallholder irrigated paddy can no longer provide the basis for a growing, or even stable, household economy. As far as energy generation is concerned, the Kinda Dam output has varied significantly. Since commissioning in 1986 the power station has generated on average 106.1 Gwh annually, which is far below the annual targeted production of 165 Gwh. In only two years, 1992, 1993, did the annual energy production exceed the target of 165 Gwh. Overall, the Economic Rate of Return (ERR) is considerably lower than originally estimated, primarily due to the decline in the international price of rice (NCEA, 1999). The original projection for 1990 rice prices, made in 1980, was US$ 700/ton. The actual midyear 1995 price was US$ 237/ton. According to the original staff appraisal report in 1981, it was projected at 21.3 pc. At the time the project was completed in 1992, it was calculated at 14.0 pc. An operations evaluation study prepared in 1996 reported the actual figure at the time was 7.4 pc. For the Government of Myanmar (the borrower), an ERR of between four and seven percent is acceptable given the visible sign of improvements over large areas previously rainfed. The Government of Myanmar is satisfied that the project has been successful. Given the lack of documentation on the project (and in particular the lack of access to official World Bank project Staff Appraisal Reports (SARs), Project Completion Reports (PCRs), and Operations Evaluation Impact Studies (OEDs), the inability of the authors to visit the site; and the inability of the authors to conduct Qualified Observer interviews in-country, it is impossible to draw any comprehensive conclusion about lessons learned. The project [appears to be] economically sustainable. However, some doubts have arisen regarding the full achievement of anticipated benefits, as the inflow into the reservoir has so far not exceeded 76 percent of the expected inflow. Though the last few years have been dry years all over central Myanmar, the possibility of errors in the initial analysis cannot be ruled out. Even with reduced inflows, the project benefits could be maximised with maximum use of rainfall, prudent water management on the farm and keeping the power station closed when there is no irrigation demand. Extension service for irrigated agriculture, especially for promotion of non-paddy crops requiring less irrigation water, has to be actively pursued and strengthened. The fact that the lender (World Bank) has no long term involvement with the Kinda Dam project, or even the borrower country, highlights the need to maintain longer term monitoring programs in order to more accurately assess positive and negative social and environmental impacts, and to learn from these experiences. Internal references Bodden, R. 1987. Kinda Dam Hydroelectric Power Plant Makes an Important Contribution to Burma’s Power Supply in Energy & Automation, IX (1987), No 6:52-53. Goodland, R. 1997. Environmental Sustainability in the Hydro Industry. Large Dams: Learning from the Past and Looking at the Future. IUCN and World Bank. NCEA, 1997. Myanmar Agenda 21. National Commission for Environmental Affairs, Myanmar.. NCEA, 1999. Kinda Dam Multipurpose Project (case study). Report presented at project national workshop under the auspices of the NCEA, Myanmar. 20 pp. World Bank, 1981. Project Appraisal Report (PAR) World Bank, 1992. Project Completion report (PCR),World Bank,1996. Operations Evaluation Impact Studies (OEDs)
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