With last year’s northeast monsoon rains failing to shore up water reserves, Chennai Metrowater plans to hire agricultural wells in Tiruvallur district to manage the shortfall in drinking water supply this year.
This could be a repeat of the scenario in 2003 when water was purchased from agricultural wells.
The water agency now plans to hire 250 wells in Poondi, Tamaraipakkam and Minjur to supply about 40 million litres a day.
For over a year now, Metrowater has reduced the volume of supply and reorganised distribution to ensure that all areas receive water every day — only, in different proportions. But the backlog is posing a challenge now.
The four reservoirs — which are crucial to providing drinking water to the city — have a combined storage of less than 30 per cent of their capacity. To maintain the current supply of 610 million litres of water a day (mld) for around seven lakh connections, it would be ideal if the reservoirs were at least half full. .
However, officials hope that the rise in groundwater level in the city after the northeast monsoon will help reduce the water demand during summer.
According to a study conducted by Metrowater, the average groundwater level was at a depth of 2.75 metres in December 2014, an improvement by 2.8 metres since last June. In some areas like Nungambakkam, Ambattur and West Mambalam, groundwater is available at a depth of 2 metres.
While areas such as Tiruvottiyur, Tondiarpet, Ayanavaram and Kottur have witnessed an increase of 2 metres in the water level, the water table in other localities such as Puzhal, St. Thomas Mount and Pallikaranai has risen by 4 metres.
The groundwater table is monitored periodically through a network of 145 wells. The water quality has also improved in several areas.
At present, desalination plants also serve to augment the water supply. When the storage in Veeranam tank dips, Metrowater would draw water from wells in Neyveli aquifer and mines to supply 80 mld to Chennai, the official said.
