New Delhi The Central Ground Water Authority (CGWA) has said the only way to augment the depleting groundwater table in the city is through rooftop rainwater harvesting.
“For augmentation of groundwater, rainwater harvesting is the only solution. For this there should be adequate supply of rainwater to match the demand. Depletion can (also) be controlled by water rationing without violating fundamental rights of people,” the CGWA said in response to an RTI application filed by environmentalist Vinod Kumar Jain.
The observation comes at a time when, according to a senior CGWA scientist, groundwater levels in Delhi are receding at the rate of 8 to 10 metres every year. “The amount of water drawn out is 250 times more than what actually seeps in. In excess of 70 per cent of Delhi’s ground water is over exploited and on the verge of drying out,” he said on condition of anonymity. CGWA, set up under the Environment Protection Act 1986 on directions of the Supreme Court, had also notified the entire Delhi region as critical.
Despite the present scenario, only a few hundred houses and institutions have a rainwater harvesting mechanism in place. “Certain positive steps were taken by the Delhi government in getting the building by-laws amended to make rainwater harvesting mandatory in all new buildings constructed on plots of 100 sq m and above. However, government buildings were excluded from the notification,” Jain said.
In its response, the CGWA said: “Directions for adopting rooftop rainwater harvesting have already been issued in NCR... It may not be correct to say they are not being implemented. But the measures could be inadequate in comparison to the load on the water table.”
The wastage of water during supply also adds to the problem. According to official records, there is a net loss of 40 per cent water during the course of distribution by the Delhi Jal Board due to leakages in its distribution pipes.
Then there are the dying water bodies, which replenish the groundwater table in the city. In an affidavit submitted to the High Court last month, the Delhi government had admitted that 169 out of 629 water bodies in Delhi cannot be revived, as they were buried.