Bhubaneswar, Sept. 23: A dip in the water table at various localities here has once again renewed the call for rainwater harvesting.

Data available with the directorate of groundwater survey and investigation show that the water table has seen a substantial dip at the three observation wells in the city.

The directorate has two wells inside the city and a third one on the outskirts.

Though the pilot project was launched last year, it has intensified its effort by rolling out a campaign vehicle that plays popular songs to draw people's attention to the need for rainwater harvesting.

It also has posters pasted on it.

In fact, the department is offering a subsidy of Rs 45,000 for individual houses with less than 200sqm roof area.

Executive engineer of the directorate's hydro project division, Bhubaneswar, Anup Das said: "Apart from the vehicle, 10 hoardings have been put up at strategic locations here to make people aware about the water table going down due to its excessive withdrawal by individuals and growing multi-storeyed complexes that are mushrooming across the city."

Uday Nath Sahoo, senior geologist with the remote sensing and geographic information system wing of the directorate, said: "Geologically speaking, recharging of the groundwater is going down every year as the works department is covering many areas near the roads with concrete."

"On the other hand, common people and private educational institutions are also replicating the same without understanding the natural process," the senior geologist said.

Another geologist of the directorate B.K. Sahoo said: "There should be compulsory use of the rainwater harvesting structures by all types of houses, especially multi-storeyed buildings."

Resident and environment expert Bijay Mishra said: "Two decades ago, the city had nice grass-covered pavements, but the way these are being replaced with concrete, god knows what will happen to recharging of groundwater."

Accusing the state government of doing little to make the rainwater harvesting stricture mandatory, the environment expert urged the civic authorities to follow the Chennai Municipal Corporation's formulae.

In Chennai, all houses seeking plan approval must have provision for rainwater harvesting.

Member planning, Bhubaneswar Development Authority, Sudhiranjan Mohanty said: "The Odisha Development Authority Act, 1982, already has provisions that directs multi-storeyed structures to have rainwater harvesting structures. All major office buildings are also asked to implement the same."

Responding to the emerging crisis, mayor Ananta Narayan Jena said: "We will discuss the issue in our council as the building plan approval authority within the corporation area rests with us."