Chennai: It’s been more than 20 days since the rain stops, but some of the city subways continue to be full of puddles.
Experts believe this because the subway is eight to 10 feet below the ground plus a water table near the subway which reaches a saturation point after the rain.
To prevent this phenomenon, City Corporation has started a expensive size to stop the water seepage by coating the subway wall with polyurethane.
But the project doesn’t help much.
“The price is around 15 lakh.
We try to do this on the Nungambakkam subway, but when we coat a part of the wall, the water finds its way and seeps from other parts.
It becomes an inappropriate process,” Karuppasamy G, Executive Engineer, Bridge Department Corporation.
After this experiment, the Civic Agency did not implement it on another subway.
As a result, several subways as they exist in GA Road in North Chennai, Thillaganga Nagar subway on Nanganallur and RBI subways in Parry are filled with puddles.
Subramanian P, Hydrogeologist with Chennai Metro Air and Sewerage Supply Board (CMWSSB), said the water table has reached saturation in many places, and the only way out is waiting until naturally subsides.
“There’s nothing much to do here.
Places like Nanganallur have arrested the surface of hard stones, and the water table there might have reached saturation,” he said.
GIS expert Dairead Krishnan suggests grouting, a process to fill the pores on the wall.
He, however, blamed the quality of poor construction that allowed water to leak ions on the road.
“The subway, when it is built, must be waterproof.
The joints must be made waterproof too,” he said.
Without the tip of water seepage in several subways, traveling through a risky puddle stretch for motorists.
It also leads to the traffic on the subway, a regular commuter said from Nanganallur.