Jal board banks on groundwater to augment water supply in Delhi

In the absence of external addition to Delhi’s water quota over the recent years, DJB, over the past five years, has been steadily increasing groundwater extraction, raising it from 86 MGD in 2020 to around 135 MGD in 2024

The Delhi Jal Board (DJB) plans to add 1,034 water extraction points and tubewells to extract 23.45 million gallons per day (MGD) of groundwater, in addition to the 135MGD currently being extracted, to meet Delhi’s rising water demand in the long term, senior DJB officials said.

Delhi has a daily demand of 1,290 million gallons per day of water. (HT Photo)

The agency said it will incur an expense of ₹94.7 crore to develop the array of groundwater extraction points along with flowmeters to measure the quantum of extraction.

“We plan to add more than 1,000 additional tubewell sites to augment local water supply with maximum extraction points proposed in south Delhi. Water extraction will only be carried out in areas where water table is high so that extraction can be done in sustainable manner,” an official, requesting anonymity, said.

In the absence of external addition to Delhi’s water quota over the recent years, DJB, over the past five years, has been steadily increasing groundwater extraction, raising it from 86 MGD in 2020 to around 135 MGD in 2024, officials said.

A water-stressed city, Delhi primarily depends on neighbouring states to meet the bulk of its drinking water demand — through the Yamuna, the carrier lined channel (CLC) Munak, the Delhi sub-branch (DSB) canals from Haryana, and through the Upper Ganga Canal via Muradnagar from Uttar Pradesh — with the water routed through nine water treatment plants (WTPs). The remaining 13.5% of demand is met through internal water sources, primarily through tubewells and Ranney wells.

To be sure, Delhi has a daily water demand of 1,290MGD, of which the DJB currently produces 1,000MGD. While the tubewell plan will augment supply by another 23.5MGD in the long term, other plans are afoot to meet the rest of the demand, officials said. The economic survey tabled by the Delhi government in March said DJB is working on a “twin-pronged strategy”, which focuses on augmentation of groundwater and surface (river) water resources.

Upstream dam storage projects, especially the Renukaji, Lakhwar and Kishau dam projects, will form part of this. On completion of these projects, seasonal allocation of water to Delhi via Yamuna will be increased.

DJB also plans to reuse treated wastewater to boost the city’s water supply, by feeding them to water bodies under the “city of lakes” project (waterbody revival project) and later extracting it through tubewells.

In 2108, the government announced it will use “Singapore NEWater model” under which the highly treated waste water would undergo advanced treatment and then pumped upstream to Palla, where it would undergo dilution and natural purification along the river. However, the project was delayed due to pending permissions, interstate cooperation and bureaucratic hurdles.

Action plan

The senior DJB official cited above said that chief secretary Naresh Kumar issued a series of directions on April 5, under which water augmentation plan was to be finalised for coming years.

According to the DJB action plan, a copy of which has been seen by HT, 700 tubewells are to be installed in south Delhi, 111 in east Delhi and another 223 in central and north Delhi. DJB plans to spend ₹56 crore on south Delhi alone, augmenting its supply by 12 MGD.

“The project would cost ₹20.2 crore for adding 111 tubewells in east Delhi, which will lead to addition of 5.55 MGD water in trans-Yamuna areas. Similarly, the central and north division has submitted a ₹18.5 crore project for adding 5.8 MGD water from sub-surface aquifers,” the official said.

Among the localities where tubewells will come up are Rohini, Rithala, Bawana, Model Town, Adarsh Nagar, Sadar Bazar, Chandni Chowk and Ballimaran.

According to the action plan report, estimates for some of the installations are under preparation as trial bores have been held up at some sites due to NOCs (no-objection certificates) not being granted by landowning agencies. “Ultimately, the project will also rely on NOC from landowning agencies like DDA and MCD,” the report said.

DJB targets to operate 5,700 tubewells this summer, up from 4,600 tubewells operational in 2020.

Delhi groundwater status

The central groundwater board (CGWB), in its ”Dynamic Groundwater Resources of India 2023” report released on December 1, 2023, noted that around 41.49% of Delhi’s area of 1,487.61 square kilometres is considered “over-exploited” due to high levels of groundwater extraction, with only northwest Delhi considered “safe” among Delhi’s 11 revenue districts, with an extraction stage of 65.96%.

Four other districts overexploited districts, according to the report, were North Delhi, Northeast Delhi, Shahdara, and South Delhi. However, the overall groundwater extraction in the city has dropped from 0.36 bcm (billion cubic metres) in 2022 to 0.34 bcm in 2023.

Diwan Singh, an environmental activist who led the Yamuna satyagraha for rejuvenating the river and other water bodies in the city, said groundwater extraction should be regulated as per the ecological limit of an aquifer. “It is not sustainable to keep extracting groundwater, as, the deeper you go, the probability of contamination of aquifers keeps rising. It is neither good for the health of the consumer nor for the ecology, but people are forced to draw water in absence of adequate supply.”

He said that the city needs to focus on reducing demand and encouraging natural rainwater recharge through drains, unpaved areas and similar interventions.