Kamala Kelkar | Delhi guzzles its groundwater, turns to rainwater harvesting

Delhi guzzles its groundwater, turns to rainwater harvesting

By: Kamala Kelkar

Struggling with depleting watertable and wasted rainwater, the Delhi Jal Board (DJB) has been trying to raise awareness towards the benefits of catching and recycling rainwater for more than a decade. Now, to ensure that its efforts don’t get washed down the drain, the water utility is looking for experienced organisations to boost its campaign.

Just before the new year, the board issued an expression of interest, asking applicants to explain how they would rekindle awareness and engagement in rainwater harvesting. Successful contenders will have 12 months to identify 600 areas where rainwater can be harvested and to prepare designs for harvest in these areas. They will also have to check the impact and maintenance of 150 existing schemes.

“There is a prime need to safeguard and replenish Delhi’s groundwater level. DJB has been actively promoting rainwater harvesting to preserve Delhi’s groundwater reserve,” DJB CEO Debashree Mukherjee said.

Rainwater harvesting systems can only be designed and built by professionals because they involve a series of canals and catch basins that funnel filtered water to the ground or store it for later use.

In 2001, DJB had asked building owners to maintain harvesting systems, but officials believe that the effort and other promotions by the government, such as rebates, are being neglected.

Nitya Jacob, programme director of water at the Centre for Science and Environment, has been working with the DJB on harvesting improvements. He said, “We need to make managing rainwater everyone’s business.”

Jacob said developers build trivial systems to appease the unspecific laws and existing basins, which are not maintained, can potentially contaminate the groundwater.

“At least 160 people have acquired rebates for rainwater harvesting. Applying for a government rebate, however, can take several months and it is a lot of bureaucratic legwork for just 10 per cent or less of the cost,” he said.

“The DJB is working to streamline the system,” Jacob said. “This campaign is a good thing.”

Shubh Sharda, president of the Mandakini Enclave Residents’ Welfare Association, who was involved in building a rainwater harvesting system that won the Chief Minister’s Best Rainwater Harvesting Award in 2007, said they catch about 22 million litres of water a year.

“We built it because the groundwater depleted to an alarming level,” Sharda said.

Sharda was assisted by the NGO Forum for Organised Resource Conservation and Enhancement. With their help, Sharda said the project, which wraps around 612 residential duplexes, was “very simple and very doable”.

An email from Mukherjee also hinted that further financial incentives might be offered as part of the new campaign.

“To give further impetus to this effort, incentives are being provided in the water and sewerage bills of consumers undertaking rainwater harvesting,” she said.

What is rainwater harvesting?

It is collection and storage of rainwater. Most of it runs off catchment areas like roofs, pavements, roads, parks, open grounds, etc. It can stored or used to replenish groundwater

Why do we need to harvest rainwater?

Groundwater levels are critical in seven of nine revenue districts of Delhi. In many areas, ground water abstraction is more than the average annual replenishment

How much water can be harvested?

One catch basin of 100 sqm saves about 40,000 litres of water every year. This is about four times the annual drinking requirement of a five-member family

Is rainwater filtered before use?

Water is filtered before use. The silt is separated and used for horticulture

What is the input cost?

The harvesting system at Mandakini Enclave had six basins. It cost about Rs 6 lakh. The RWA applied for a DJB rebate and got Rs 1 lakh. Most applicants get a rebate of Rs 50,000.

What are its benefits?

Apart from replenishment, harvesting improves the quality of groundwater. It reduces soil erosion and minimises choking of storm water drains and flooding of roads.

Source: Delhi government website (http://is.gd/4vbMAP)


The Delhi Jal Board has a reward system in place for those who build rainwater harvesting systems. Although this is a good incentive, the process is tedious because it takes several months.

Who can apply: RWAs, housing societies, schools, buildings, hospitals, etc

Maximum rebate: Rs 1 lakh or 50 per cent of total input cost

Eligibility: Applicants must first get design plans approved by the Central Ground Water Board to be eligible for the DJB reward