BHUTAN: 1 out of 3 Dagaps to be affected

FROM KUENSEL NEWSPAPER

BY SONAM PELDEN


The Sankosh Multipurpose Project dam site near Kerabari, that would generate 4060 MW of power by 2020
Sankosh Project 28 July, 2010: When work starts on the country’s biggest hydropower project on the banks of the Sankosh river, one-third of Dagana’s population (9,356 people out of about 25,070) living in eight gewogs will be affected, says a study on the impact of the project by the Indian council of forestry research and education (ICFRE).

The eight gewogs are Tashiding, Tsendagang, Sankosh Town, Deorali, Lhamoizingkha, Nichula, Barsong and Rangthaling.

The 4,060 MW multipurpose project would acquire 7,304.90 hectares of land, of which 6,999 hectares would be submerged, says the study. Of the total land that would be submerged, 5,900.70 hectares is forest and 1098.30 hectares private land.

It was also found that vegetation of the submergence zone contains 250 species of plants and trees, including 58 species of medicinal plants and four rare species of plants.

Fourteen species of mammals, such as Assamese macaque and evidence of Asian elephants, sambar, sloth bear and golden langur, 86 species of butterflies, and 21 species of fish were also found during the study. “Due to the reservoir, the change of agriculture and forest land to water body is permanent,” says the study.

The findings were shared yesterday during a meeting between officials from the Tehri hydro development corp (THDC), the ICFRE, the department of energy (DoE), the Druk Green power corporation (DGPC), national environment commission (NEC) and the department of roads (DoR).
But it also has huge benefits, they said. The project would develop the area, create employment opportunities, create infrastructure facilities, development of roads will increase easy access, networking and promote business, increased accessibility and project activity would contribute in improving the livelihood of local people and further uplift the local economy. It would also bring in additional facilities, such as schools, hospital and drinking water.

“The project affected people may be provided training and financial help for entrepreneurship development,” states the study. “Preferential employment in semi-skilled and skilled categories will enhance the socio-economic status of the project affected families.”

The project, said the director general, department of energy (DoE), Yeshey Wangdi, is the largest project undertaken to achieve the target of generating 10,000 MW by 2020. “It alone contributes 40 percent of the 10,000 MW target,” he said.

With the detailed project report (DPR) to be completed by March 2011, Yeshey Wangdi asked the THDC to minimise private land acquisition. “We’d suggest to see and accommodate on the left bank of the river, where there is government land available” he said.

Explaining the features of the dam, THDCL’s additional general manager, RK Vishnoi explained that there would be two dams built, a main dam that would generate 4,000 MW of electricity, and the lift dam 13 km downstream that would generate 60 MW of energy. The power house would be built on the left bank near the main dam.

The dam, which would be built near Kerabari in Bhutan, would stand 265 m high, with the reservoir running 52 km upstream from the dam site. “It would generate 4,000 MW of energy at peak hours, when the flow of water is high,” he said. “But the flow of the river would be regulated so that there is 4,000 MW of power generated throughout the year.”

The reservoir’s full capacity of water level is 390 m, which can store 6,325 cu m of water, said RK Vishnoi. According to their seismological studies, they expect 7.5 magnitude earthquakes in the project site.

Participants pointed out that the studies have not taken into account the glacial lake outbursts floods, to which RK Vishnoi said that the dam is designed for 17,455 cu m per second water flow. “If the project is hit by a flood of this magnitude, it would safely manage the flood,” he said, adding that the project is not very vulnerable to GLOFs.

The finance aspect, such as costs involved, was also not clear, said participants.

The last flood in that region, they said, was in 1994. However it is the landslides, they said, which would be responsible for the deposition of sediments in the project area. High rate of sediments in the dam would mean a decrease in the volume of water the dam could store, explained officials.

However, the study for the feasibility of building a concrete dam instead of a rock-fill dam is still on. It would be done by September this year. Concrete dam is usually the preferred choice for constructing dams, said engineers, especially for places in high seismic zones; since a rock fill dam, although cheaper, requires lots of processing, such as blending of gravels.

Although studies are still underway at the project site, TDHC officials said that incessant rain lately has made it difficult and risky to work. “Another issue that needs to be taken up immediately is to improve the access to the project site,” said RK Vishnoi. “It needs nine bridges and a 16 km road and, for a huge project like this, it could take up to two years,” he said.

The project that would take about eight years to complete would channel the water downstream to India for irrigation.

Meanwhile, the Bunakha project along the Wangchu for which a DPR is still underway, would affect 3,248 people in Chapcha, 1,856 in Geling, 232 in Bunakha and 150 in Chaina chia under Chukha district