Water board moots plan to replenish water table in State

Water board moots plan to replenish water table in State
SRAVANI SARKAR

NAGPUR, MAY 10: In its bid to deal with the problem of declining ground water levels in several parts of Maharashtra, the city-based central region office of the Central Ground Water Board (CGWB) has come out with a master plan for artificial recharge of the ground water in the State.

Ground water builds up through percolation of surface water into ground. Overexploitation leads to decline in the levels resulting in non-availability of ground water. By way of artificial recharge, CGWB has suggested a method, wherein simple low cost structures are constructed in the affected areas, so as to artificially induce the surface water to percolate into ground, in order to maintain the ground water level.

The ambitious master plan envisages a two to five metre rise in ground water level over a area of 15,600 square kilometres (spread over 422 watersheds) in the rural parts and assured domestic water supply for over eight lakh urban population (in 232 towns).

Similarly, a total of 5,33,600 hectares of additional land would be brought under assured irrigation as a result of the recharge, it has been claimed. The overall estimated cost for implementation of the plan is Rs 3,062 crore.

A very detailed document -- the master plan delineates the areas watershed-wise where recharge is necessary and possible -- outlines the ground water storage capacity and surface water available for recharge and suggests the possible recharge structure that would be feasible in these areas along with approximate cost.

The master plan was released recently at the hands of Dr N P Hirani, Maharashtra Minister of Water Conservation. The CGWB authorities now plan to send the document to the related state departments of water conservation and rural development, hoping its quick implementation.

The CGWB had brought out a report late last year mentioning that in various parts of the state, ground water levels showed noticeable decline over the last decade (ending 1998).

The districts found to be worst affected were Aurangabad, Ahmednagar, Parbhani, Jalna, Latur, Osmanabad, Solapur, Jalgaon, Yavatmal, Amravati, Nagpur, Chandrapur and Bhandara. In majority of the areas, water levels had declined by two meters, while in some - including parts of Jalgaon district and Warud in Amravati district, water levels had gone down by a drastic four meters (reported by this newspaper in December 1999).

Later, the CGWB team undertook a massive operation to come out with remedial guidelines, which was put together in the form of the master plan.

Santosh Kumar Sharma, regional director of the CGWB, told The Indian Express that a multi-disciplinary approach has been adopted in preparing the master plan. CGWB's successful experiences regarding artificial recharge at Warud (Amravati) and Jalgaon formed the basis of the study.

Data was collected watershed wise to arrive at the figures of storage spaceavailability and the surface water availability for recharge purposes. It was calculated that the total surplus surface water (giving a concession for the water committed for various present and under-construction irrigation projects) available in the three major river basins - Krishna, Godavari and Tapi - is 28870 million cubic metres (mcm).

For storage space availability, areas showing deep levels [more than three metres below ground level (bgl)] and declining trends were considered (based on the previous CGWB report). The feasible area in entire state was calculated as 65,267 sq km. The storage space (unsaturated zone) available has been estimated as 2,81,645 mcm and the surface water required calculated as 15003 mcm (considering 75 per cent efficiency of recharge structures).

For planning purpose, the area-wise amount of surface water availability and storage volume were matched to arrive at the feasibility of the scheme. It was finally calculated that surface water to the extent of 2318 mcm could be utilised for artificial recharge methods.