At a time when summer and heatwave conditions have extended well past May, the Tiruchi Corporation is facing a significant drop in water table in the vicinity of its pumping stations on the Cauvery and the Kollidam riverbeds.

The Corporation has an installed capacity of about 160 MLD (million litres daily) at various sources in the riverbeds of the Cauvery and the Kollidam. The city requires about 150 MLD of water to meet the requirements of about 11 lakh population. While the Corporation gets 80 MLD from the Kollidam, it sources about 65 MLD from the Cauvery through its pumping station and wells. The Corporation gets seven to eight MLD from the source points at Jeeyapuram, Boothapuram, and Tiruverumbur, which are operated and maintained by the Tamil Nadu Water and Drainage Board (TWAD).

The city generally faces strain in supply of drinking water in summer from March to May. There were no major issues in water supply in March, April and May. The civic body was drawing almost close to its capacity until recently. The summer rain came as a relief to the water managers to an extent. However, it is said that it is struggling to maintain yield for the last few weeks.

Significant drop in yield

According to sources, there has been a significant drop in water table in the Cauvery and the Kollidam riverbeds where pumping stations were located. Though the check dam at Kambarasampettai is meeting its purpose of maintaining groundwater recharge at the collector wells, the groundwater has gone down drastically in the close vicinity of the head works, thereby putting pressure on the water managers to maintain usual supply. Similarly, the water table in the Kollidam has also gone down in recent weeks.

An official of the Corporation told The Hindu that the water level had gone down at the points of water sources as the Cauvery and the Kollidam had gone dry since the closure of the Mettur dam in February. However, the yield was being maintained at the usual level with the operation of pumping stations for 22 hours to 23 hours a day. The impact of the summer in June was closely observed. If needed, additional steps would be taken to ensure regular yield from the pumping stations until the onset of northeast monsoon.