The delay in the onset of the northeast monsoon is becoming a cause of worry for the residents as the groundwater table in Chennai and suburbs has been receding over the past two months due to lack of recharge.
S. Prema, a resident of Villivakkam, said “the open well in my house dried up three months ago. Whenever there is light shower, the water level rises to one foot in the well. My 20 feet well overflowed during monsoon last December.”
Residents of many areas, including Adyar and Kellys, manage with the limited resource of piped water supply.
For those dependent entirely on groundwater, particularly in suburban areas, the problem is severe. Suchetha Kumaradev, a resident of Raju Nagar in Thoraipakkam, said the water level in the well in her house has declined to two feet.
“I use groundwater minimally for the past one month and purchase tanker load of water for domestic needs,” she said.
Hydro geologists in the city said that there had been a slight decline in the groundwater level in the city as there was no uniformity in rainfall.
Officials of Chennai Metrowater said the average water level in the city had gone down by 0.2 metre in a month. While the water level in Chennai was 4.1 m in August, it dipped to 4.3 last month. Similarly, there has been a fall by 0.6 metre in water table in the past one year. Last year, the average water level stood at 3.7 metre during September.
However, officials of the Meteorological Department said the northeast monsoon is likely to set in by October 27 or October 28. Normally, the monsoon sets in by October 20. There has been a slight delay this year, they added.
Deputy Director General of Meteorology, Regional Meteorological Centre, Y .E. A. Raj said “There has been a deficit of 74 per cent in rainfall from October 1. But, the weather pattern indicates onset of monsoon in a few days. We expect normal rainfall that would cover the deficit experienced so far.”
The city has had delayed onset of monsoon in the past as in 1998 when northeast monsoon set in on October 28. There have been occasions of monsoon setting in during November in at least nine years in the last 100 years, he added.
Meanwhile, Water Resources Department, a wing of PWD, has started releasing about 280 cubic feet per second (cusecs) of water from the Poondi reservoir to the waterbody in Chembarambakkam to step up storage for drawal by Metrowater. Similarly, about 250 cusecs water would be discharged to the Red Hills reservoir from Saturday to facilitate extraction of water for city supply, said a WRD official.
While Chembarambakkam reservoir has only 371 million cubic feet of water (mcft) as against its capacity of 3,645 mcft, the one at Red Hills has 1,000 mcft against its capacity of 3,300 mcft.