Pits recharge groundwater

Bed filled with gravel and mud helps water seep through to the ground

The Central Ground Water Board (CGWB) feels that laying of concrete flooring in SWDs in the City stalls efficient usage of rainwater. Regional Director of the Board T M Hunse, pointed out that pits are in place at SWDs in all metros, to tap the rainwater.

“These water harvesting pits ensure in creating a bed, filled up with gravel and mud. This ensures that water seeps through them to the ground,” he observed. This would ensure that the groundwater is recharged whenever rain lashes City, Hunse added.

Belgaum example

The Sambra Air Force station in Belgaum created such harvesting pits within its premises recently to tap rainwater.

“This has clearly resulted in an improvement in groundwater level within the station and its surroundings,” the Director pointed out.

The efforts by BWSSB to promote rainwater harvesting in individual houses is laudable but a concrete difference can be made only when the government goes in for concrete measures, Hunse pointed out.

Beyond permissibility

The presence of nitrate is very high in parts of 83 taluks in the State.

“They exceed the permissible limit of 45mg/litre. The same is the case with fluoride, the concentration of which exceeds the permissible level of 1 mg/litre in 54 taluks,” he stated.

Rainwater, that infiltrates the ground through the pit will ensure that the nitrate content in water gets diluted, thus purifying the groundwater, the Director stated.   

The absorption of rainwater in this manner within the pits will prevent water from flowing on to the roads and flooding areas, he added.

On the reason why the concreting was being done at SWDs in the City, another source pointed out that work related to SWDs are given by BBMP on a piece-meal basis to different contractors. The latter are interested only in completing their work and are not worried about preserving the rainwater.  

Despite repeated attempts the BBMP officials declined to respond on the issue.