One day in September last year, months after the worst of Delhi’s summer had passed, the Delhi Jal Board (DJB) found it had an extra 20 million gallons of water in one of its seven water zones. The state utility decided to divert the surplus to residents of the south-western suburb of Dwarka, reeling under a perennial water shortage.

Meeting demand: People collecting water from tankers in Dhansa village of Najafgarh (top) and Reserve Bank of India Colony, New Delhi. H.C. Tiwari / Hindustan Times. Many neighbourhoods pay private carriers for water supplied by Delhi Jal Board. Ankit Agrawal / Mint

The main lines to Dwarka ran through several West Delhi neighbourhoods which had already received 20 million gallons, leading water department officials to assume that the extra water would flow to Dwarka.

It didn’t—it was used up by neighbourhoods on the way— and in the process threw up a unique challenge in devising water distribution networks.

“In electricity, you just have to plug it into a network and power is available everywhere. In water it is different. We (have to) plan for hydraulics, the way the water is carried," said Ramesh Negi, chief executive officer of DJB.

With unplanned construction increasing and as stand-alone bungalows give way to high-rise apartments in cities across India, the water department’s carefully calibrated pressure hydraulics are not measuring up.

Ageing networks in overcrowded cities have compounded the problem of water distribution. The outcome is restricted water supply in most urban areas, as it is in the case of newly built-up neighbourhoods such as Dwarka, where some one million people live around 20km from the central business district.

The problem

Delhi receives some 800 million gallons of water per day from the Yamuna and Ganga rivers as well as groundwater. In a city of some 16 million, there are some 1.7 million water connections, of which around half are metered. Nearly half the water, supplied through the 9,000km of pipes in the city, leaks out, according to data provided by the Centre for Science and Environment (CSE).

The problem, says DJB’s Negi, is that water supply schemes are approved according to the city’s long-term masterplan. However, building activity rarely conforms with the masterplans, as people keep adding extensions to their homes, or new developments spring up.

The result is that high density areas, with a lot of unauthorized, unplanned construction—which is a feature of most of India’s cities—get less and less water.

“If you have Defence Colony (a tony south Delhi neighbourhood), which is a planned area, the supply will be static," Negi said.

It’s not the case with other, more crowded areas.

The lack of planning in the 1970s and 1980s has led to water distribution systems becoming obsolete, said M.N. Thippeswamy, a former chief engineer with the Bangalore Water Supply and Sewerage Board. And even after most cities initiated comprehensive city planning in the last couple of decades, most development agencies have been unable to anticipate the pace of growth.

City authorities focus on one region and growth happens elsewhere, said Thippeswamy, adding that in Bangalore, the water utility planned water requirements for 30 years, “but unfortunately it is not enough for even 15 years".

The alternative

One man’s discomfiture is another’s business. Private water tankers have moved in to meet the shortfall in supply at rates substantially more than what they would otherwise have paid. They cater to areas that are either out of DJB’s water network or where not enough water is available.

A CSE report estimates the number of tankers at anywhere between 900 and 1,200 in Delhi.

The utility supplements this with several hundred water tankers—its own as well as hired—to deliver the water which it is unable to provide through the water mains.

“We pay less for milk and more for water," said Devendra Gupta, 68, who lives in Guru Apartments in Dwarka’s Sector 6. “The water pipes have no supply. So people are starved for water in Dwarka."

Residents in the apartment complex supplement DJB’s supply by ordering between one and five tankers per day, depending on how much water flows from the water utility, said another resident, who did not want to be named.

In June this year, when temperatures peaked, the 100-odd residents of the block paid some Rs1,900 each to the private water suppliers, he added.

Similarly, in south Delhi, Jata Shankar, a driver for a private water carrier guides his immense water tanker through rush hour traffic several times a day to deliver water to Reserve Bank of India Colony in Vasant Vihar in Delhi, because Jal board’s pipes run empty.

Shankar’s truck empties its contents into the neighbourhood’s water tanks, from where it is routed to the apartments within the complex.

The residents pay DJB directly for the water, while the water carrier is paid for transporting it from the water utility’s tanks a few kilometres away, said the owner of the water service, who did not want to be named.

The situation is unlikely to change immediately. Negi says with Delhi’s water availability governed by inter-state agreements dating back to 1994, the amount of water flowing into the city is poised to stay constant. The only way to boost supply to meet growing demand is to plug the existing leakages in the network.

Thippeswamy maintains that for a long-term solution to address growing water needs of Indian cities, administrations must opt for an integrated approach—replace old assets, reduce water losses due to leakage, aggressively promote water conservation and rainwater harvesting and find a way to reuse waste water.

“Whether in Bangalore or Mumbai, there are not adequate funds for replacing assets. In Bangalore in some areas, even 100-year-old pipes we are not able to replace," he said. The only solution, he says, is to earmark funds and start work on replacing ageing assets.

“Unaccounted water cannot be avoided. Even Singapore has 7.5% unaccounted water. But if Indian cities can bring unaccounted water (levels) to 10% (of total supply), it will bring back a lot of water," he said.

Padmaparna Ghosh contributed to this story.