Shillong, June 10: Rampant mining of sand and stone in catchment areas is threatening the life span of the dam of Greater Shillong Water Supply Scheme, one of the main sources supplying potable water to the residents of Shillong city and also its outskirts.
Deputy chief minister in-charge, public health engineering department, R.C. Laloo, today said in the state Assembly that though the dam was designed for 50 years, considering the ongoing environmental degradation of the catchments of feeder river, the life span of the dam was expected to be cut short.
Laloo, while replying to a question raised by the Opposition United Democratic Party (UDP) legislator, Paul Lyngdoh, said as a first step to control the sedimentation at the Mawphlang reservoirs, construction of the silt retention dams across Umiew river and Umtyngar river was undertaken as measures to overcome the threat. Umtyngar river is also flowing towards the dam.
Expressing concern over the threat the dam is facing because of rampant sand mining, washing of vehicles, dumping of solid waste, including open release of human excreta and other harmful detergents to the feeder river, besides silt and sedimentation, Lyngdoh sought for immediate steps from the government to arrest the problem.
Laloo, however, promised to take action like banning sand mining and stone quarry without affecting the livelihood of the people, washing of vehicles and dumping of waste in the feeder river and areas close to Umtyngar river besides steps to safeguard Umiew river as well as its tributaries.
“The main factor is silt and if it increases on the river bed, there is every possibility that the life span of the dam may be shorter than expected. To tackle the problem, the government is mulling to construct retention dams in the catchment areas,” Laloo said, even as he assured that the government would also follow the provisions of the Meghalaya Protection of Catchment Areas Act, 1990, by involving land owners and headmen to address the issue.
The greater Shillong dam was built in the late eighties across the main feeder river, Umiew river, at Mawphlang about 25km from here.
Construction of the dam started in January 1979 and according to a report of the Comptroller Auditor General of India, 2003, the original estimate for the water supply project was Rs 23.90 crore but till 2003, the amount was later increased to Rs 76.77 crore.
The dam has three phases. Phase III is being taken up under the centrally-sponsored Jawaharlal Nehru National Urban Renewal Mission (JNNURM) but the scheme is yet to materialise even after nearly six years.
The construction of the dam’s third phase at an estimated cost of Rs 193.74 crore commenced with the laying of foundation stone by former President Pratibha Patil on October 22, 2008.
The government is targeting to provide 135 litres water per day per capita from the scheme to the 3,54,325 population of Shillong urban agglomeration.