Tamil Nadu plans Rs 22,000-crore project to increase water storage, cut flood woes in Chennai

CHENNAI: The Water Resources Department has formulated a Rs 22,004-crore project that would augment water storage by 20.50 thousand million cubic feet (tmc ft) while also ensure permanent flood mitigation for the vulnerable areas in the city and surrounding areas, Minister Duraimurugan informed the Assembly on Friday.

Elaborating on the project, Chennai City Water Supply Augmentation and Flood Mitigation Resilient to Climate Change, the minister said it would be designed to address both flood mitigation and rainwater conservation for deficit years in and around Chennai city.

"The proposal aims to create an additional storage capacity of 20.50 tmc ft to meet the drinking water requirement of Chennai city and to find permanent mitigation measures for the flood-vulnerable areas in and around the city," he said.

Presently, the combined capacity of six reservoirs in the Chennai region that supply drinking water to the city is 13.222 tmc ft, while the annual demand for drinking water and industrial purposes is about 22 tmc ft. By undertaking the project, the storage would go up to 32 tmc ft by 2035, which would meet the requirement calculated as per the projected population growth, he said.

"It is very imperative to protect Chennai city from recurrent flooding and drinking water problems. Short and long-term flood mitigation works are proposed to be taken up to avoid recurring flooding in Chennai city," said the policy note for the year 2023-24 tabled in the Assembly on Friday.

Citing the December floods that brought the city to its knees, the minister said a serious impact of climate change has been observed on tropical climate areas, causing unprecedented flash floods in many parts of Chennai and surrounding districts.

"As pre-monsoon work has been taken up and carried out effectively in Chennai and surrounding areas, flood water quickly drained even if it rained heavily. This year, we will take up pre-monsoon work at a cost of Rs 30.5 crore," the minister said. "By desilting the four waterbodies in Chennai, storage will go up by about 1.904 tmc ft," he added.

The department has also completed the creation of a new reservoir by upgrading the capacity of Kattur and Thattamanji twin tanks in Tiruvallur at a cost of Rs 62.36 crore. It would augment water resources to Chennai and provide irrigation facility to 5,804 acres of ayacut, he added.