Rain boosts storage in city reservoirs


Heavy rain in the catchment areas of the city reservoirs over the weekend is bringing steady inflow into the water bodies that cater to the drinking water needs of Chennai residents. While more inflow is needed for Chennai reservoirs to fill up, the storage is steadily on the rise in several other dams across the State too.

According to the Water Resources Department, Red Hills received the highest volume of inflow with 967 cusecs on Monday among the city reservoirs. The combined storage of the four reservoirs stood at 568 million cubic feet on Monday and nearly 200 mcft of water was added in two days. While the available resource is still much lower than the capacity of 11,057 mcft, it would help in supplying water to the city for a month. Chennai residents may have to wait till the onset of the northeast monsoon for improved water supply.

Officials said the Red Hills reservoir received good inflow as 14 lakes upstream are either brimming or nearly touching their full capacity. Though the reservoirs received intermittent showers, it did not translate into inflow because it did not rain uniformly in the catchment areas and much of the flow percolated in the parched lakes. “We expect quicker realisation of inflow whenever it rains from this month,” said an official.

Hopes up for Veeranam

Meanwhile, with the storage in Mettur dam in Salem district touching 58,358 mcft on Monday, the prospects of water reaching the bone-dry Veeranam tank, which augments water supply to Chennai in a fortnight, seems bright.

Officials of WRD said it would take five or six days for water from the Mettur dam to reach Kallanai. About 10% of the water from the Kallanai would be released to Veeranam tank through the Vadavar channel.

The southwest monsoon has proved favourable for the dams in other parts of the State as well. Heavy spell of rain in the past two months across the State had boosted water level in major dams, including Mettur, Bhavanisagar in Erode district, Mullaperiyar dam and Sathanur dam in Tiruvannamalai district. Many among the 15 major reservoirs have a better storage of nearly 50-60 % of their capacity compared to last year.

Weather blogger Pradeep John who runs a Facebook page, Tamil Nadu Weatherman, said the State recorded 414.3 mm during southwest monsoon, which was highest since 1996.

Though the rain spells were limited to three or four this season, each spell extended to four days and this generated sufficient inflow into the dams. “Dams like Vaigai (in Theni) and Papanasam (Tirunelveli) that were almost dry now have a minimum of 30% of storage. Only reservoirs in few districts like Chennai and Cuddalore need Northeast monsoon to replenish resources,” he said.

More rains predicted

Meanwhile, the Meteorological Department has forecast that parts of north Tamil Nadu and Puducherry would receive scattered rainfall for two more days.

Two weather systems – a cyclonic circulation over Rayalaseema and neighbourhood and another trough running from north Odisha to north Kerala – would influence rains over the State, said officials.