The steady rainfall during evenings for the past few days spurred by convective activity has eased the stress on groundwater resources in the city marginally and saved the water table from further depletion.
As the intermittent showers have helped to boost groundwater level, the dependence on Chennai Metrowater’s tanker trips has come down slightly in the past two days.
While most parts of the city enjoyed widespread rainfall on Thursday night, raising hopes of copious inflow into the city’s reservoirs, the storage in the water bodies, including Chembarambakkam, had gone up only by 18 million cubic feet, which is adequate only for a day’s supply. The lakes remain largely dry and need many more rainy days.
However, the evening showers have helped recharge of groundwater and slightly eased the burden on Metrowater tanker trips. With piped supply dwindling fast, residents have turned to groundwater and tanker supply to cater to their needs.
Officials of the Metrowater noted that the number of trips had climbed to 8,000 trips per day this month. The recent rainspell had brought down the daily trips, including those on payment, by 200 and nearly 7,800 trips are being operated now. This indicates that groundwater table has witnessed a marginal improvement. With the available sources, including in agricultural wells and quarries, the water agency plans to sustain the present supply of 470 million litres a day till the onset of the northeast monsoon. Experts note that the rain spell has saved groundwater from alarming depletion as most residents are extracting the available resource to bridge the gap due to the dip in Metrowater supply.
Sekar Raghavan, director, Rain Centre, said showers across the city during evenings have helped sustain the water table in spite of heavy extraction of resources. For instance, the water table has seen only a minor dip by 0.2 metres and stands at 5.5 metres in places like Mylapore and replenished the shallow aquifer in open wells. “The impact was felt in houses with open wells. We dug an open well for a depth of 30 feet in an apartment complex at CIT Colony, Alwarpet and it was dry. Now, it has water for nearly 28 feet. Proper measures to harness rainwater would help in better recharge,” he said.
Rain to continue
Meanwhile, showers lashed many parts of the city on Friday. Officials of the Meteorological Department said several parts of the State would continue to receive thundershowers on Saturday too and it may be heavy in some places.