Chennai: The northeast monsoon season has ended without filing up the city reservoirs but the normal rainfall received have recharged the groundwater table which has increased by nearly 2.84 metres, compared to the pre-monsoon level. Before the onset of the NE monsoon, the groundwater level in the city was 5.59 m from the surface but after the end of the monsoon the water level has improved to 2.75 m resulting in an overall rise of 2.84 m, according to the data of Chennai Metropolitan Water Supply and Sewerage Board (CMWSSB) which monitors water level in 145 observation wells. In addition, the water quality (total dissolved solids) has also improved in the range of 200 to 600 ppm.
The groundwater table in Balaji Nagar, Ambattur, recorded a maximum rise of 8.55 m which was 10.65 m deep before the monsoon, and rose to 2.10 metres. The water level at St Thomas Mount, Pallikaranai and Puzhal rose by over 6 m while in Anna Nagar West, Koyambedu, West Mambalam, Saidapet and Little Mount recorded an average rise of 3 m. In north Chennai, the groundwater table in Thiruvotriyur, Tondaiarpet, Kottur and Ayanavaram increased by 2 m, while in Geoge Town, Mandaveli, Besant Nagar and Nungambakkam the average rise was 1 m.
Attributing the increase to door-to-door rainwater harvesting campaign carried out by the board, a CMWSSB official said awareness on RWH is carried out among the residents of Chennai city every year before the onset of monsoon and about the installation and maintenance of RWH structures in all buildings, whether it belonged to government, company, institution or residential.
Even though the city received normal rainfall of 73 cm during the NE monsoon, it failed to fill up the four reservoirs which supplies drinking water to the city.
The combined storage capacity of the four reservoirs - Poondi, Red Hills, Chembarambakkam and Cholavaram - stood at 3,132 mcft which is 27 per cent of the total storage capacity of 11,057 mcft. On the same day last year, water storage stood at 3,242 mcft. However, the metro water official said they will be able to supply drinking water to the city with the support of Krishna water, Veeranam and two desalination plants. “The situation is like last year; we are hopeful of meeting the city’s water needs,” the official said.
