CHENNAI: Ahead of the Northeast monsoon, the Tamil Nadu PWD Senior Engineers Association (Tansea) has urged the state government to increase water storage by desilting small tanks and reservoirs. It recently submitted a detailed report to the government outlining these proposals.
A Veerappan, state general secretary, Tansea, told TNIE, “To increase water storage around Chennai, desilting 507 out of 1,550 tanks in Tiruvallur, Chengalpattu, and Kancheepuram is crucial. This will help store 3.75 tmcft of water, which can be diverted to reservoirs through pipelines.”
Desilting the Chembarambakkam, Poondi, and Puzhal reservoirs to deepen them by a metre could store an additional 1 tmcft water each, he said, adding that the project may cost Rs 800 crore which could be partly compensated by selling the silt to other government agencies such as the state highways who need them.
He also recommended dredging the Buckingham Canal by a metre and removing encroachments along its banks to prevent flooding.
“Chennai Corporation pumps floodwater into the canal and diverts it to the sea during the monsoon. Instead, deepening the canal would be a long-term solution,” he said.
N Kailasapathi, Tansea general secretary (headquarters), emphasised the importance of constructing checkdams.
“Thirteen checkdams have been built along the Kosasthalaiyar. Similarly, four checkdams each should be built on the Cooum and the Adyar to reduce flood impact and improve groundwater levels,” he said.
He also urged the government to consider constructing underground water storage systems in major reservoirs similar to those used in countries like China, US, Australia and Singapore.
Responding to the suggestions, a senior Water Resources Department official said, “We began desilting Poondi reservoir in 2021, with plans to complete the work in five years. However, technical issues temporarily halted the project.” A sum of Rs 20 crore is allocated annually for flood mitigation, but it has increased to Rs 30 crore this year. Financial constraints have hindered extensive desilting in most tanks, he added.