As part of its efforts to save flood waters, the Water Resources Department (WRD) has proposed to construct three check dams across various waterways in Tiruvallur district.
One of them, built at Illupur, about 20 km upstream of the Poondi reservoir, will help augment Chennai’s water supply. The department has submitted the proposal to build two check dams across Kusa river in Pallipattu taluk at Sangeethakuppam and Kumarajapet and another structure in Illupur at a cost of ₹26.75 crore.
Officials of the WRD said the project to build the 230-metre long check dam will be implemented across the Nagari river at Illupur near Tiruttani. This will partially fulfil the city’s drinking water demand by providing 30 million cubic feet of water.
The ₹18-crore storage structure will increase the groundwater potential in agricultural wells located within a 3-km radius and stabilise irrigation on 296 hectares of land.
Nagari tributaries
Lava and Kusa rivers are tributaries of the Nagari river that originates in Andhra Pradesh. Of the 17-km-long Kusa, about 4 km flows within Tamil Nadu limits. Both rivers join near Pallipet to become the Nagari and flow for 69 km till the Poondi reservoir. The reservoir mainly gets its inflow from these waterways apart from the Kosasthalaiyar.
Following the 2015 floods, farmers of Sangeethakuppam, Venkatarajukuppam, and Veliyagaram villages made representations for two check dams to prevent floods in the Kusa that inundated several agricultural fields.
Officials said the 66-metre check dam at Sangeethakuppam, nearly 65 km upstream of the Poondi reservoir, would help recharge 58 agricultural borewells around it and benefit nearly 53 hectares.
“Several villages depend on the Kusa and the Nagari for their drinking water. The check dams will retain surface water and protect the river’s sand bed,” an official said.
Similarly, an 80-metre check dam to be be built at Kumarajapet to enhance groundwater potential would help recharge about 40 agricultural borewells. The flood banks of the Kusa would also be strengthened.
“We have already constructed four check dams upstream of the Poondi reservoir. The aim is to build such facilities at every 3-4 km of the rivers to store water. We plan to start work for new check dams in a few months,” the official added.
