The Water Resources Department is set to resume de-silting work at Poondi reservoir.
Built across the Kosasthalaiyar river in 1944 in Tiruvallur district, the reservoir is one of the major sources of water for the city with a capacity to store 3.2 tmcft water. At present, the reservoir has 2.9 tmcft of water. Surplus water from the reservoir is diverte to other similar storage facilities. De-silting has not been taken up in the reservoir on a large scale ever since its construction. It’s storage capacity may have been reduced by at least 10%-20% due to silt deposits for decades, according to the department.
The department started work to remove silt in August last year. But the work was stopped following heavy rain and water in the reservoir touching maximum level. “We plan to resume de-silting work in a few weeks once the water level drops. Work will be initiated in the periphery of the water spread area where the lake bed dries up,” said an official.
About 440 cusecs of water is being diverted to other reservoirs like Red Hills. On an average, there is a decrease of 20 mcft daily.
About 6,180 cubic metre of silt was cleared from Poondi reservoir last year. The department has estimated to clear 2.04 crore cubic metre of silt. The work would be taken up in phases and the entire project would be completed in 10 years, officials said.
The project would be executed as a revenue generation model. The contractor would be allowed to sell silt removed from the reservoir after depositing an amount. The silt removed could be used for filling purposes and in brick kilns.
It is estimated that a revenue of ₹257.94 crore may be generated through clearing of silt from Poondi reservoir. Decision would be taken on resuming similar long-pending work in Chembarambakkam and other reservoirs depending on the storage in the coming months, officials added.
