By Nate Sulat       

Americans are no strangers to drought, but thanks to our advanced water storage system, most of us are able to wash clothes, bathe, cook, and clean with relative security. In Chennai, India, however, the reality is very different, says Stanford researcher Veena Srinivasan. With the support of a Woods Institute Environmental Venture Project (EVP) grant, Srinivasan and her Stanford colleagues Lawrence Goulder (professor of economics) and Steven Gorelick (professor of Environmental Earth System Science) have been studying water management in Chennai, India’s fifth-largest urban center, where water storage systems suffer from a lack of efficiency and, more importantly, reliability.

“In theory, cities get water via utilities through a pipe network,” explains Srinivasan, a graduate of Stanford’s Emmett Interdisciplinary Program in Environment and Resources (E-IPER). “In Chennai, a lot of the water comes from consumers’ private wells in addition to the pipe network, and also from private tankers in years that you don’t have enough water in either the aquifer or the pipe network. The mystery for us was, how do we explain why consumers have this very complex behavior? Why did it evolve this way?”

Chennai (formerly Madras) is home to more than 4.5 million people with an additional 2.5 million in the suburbs. While the inner city is supplied by a pipe network, the suburban areas are not. Unfortunately, the use of private wells has proven unreliable in the suburbs, which account for most of the region’s growth. That’s because Chennai’s aquifer is very shallow. “In a wet year it fills up, and in a dry year it dries out,” and there is no intermediate between the two extremes, Srinivasan explains. A dry year in Chennai is defined primarily as the absence of water in the aquifer. Such conditions occur every four to five years, offering little water security for the population.

Chennai’s response has been to truck water tankers into the area—an inadequate remedy, says Srinivasan: “It’s very expensive, it causes traffic congestion, trucks run over people,” she says. “So that’s probably a really bad idea.”            

Srinivasan’s solutions reflect the complexity of the existing system. Her two main recommendations are (1) raise the price of water from the pipe system and (2) implement a “dual-quality” system in which all of the water pumped into the pipe network is treated at a central facility, while community wells continue to supply lower quality, untreated water.            

These recommendations draw on a key theme in water management, namely that high-quality treated water is only necessary for cooking and drinking. In fact, most water used domestically goes to toilet flushing, bathing, and laundry. Srinivasan maintains that raising the price will reduce the demand for piped water. As a result, consumers will move to well water for most activities and use the pipe system only for food and drink. Decreased demand also would allow the system to expand into the suburbs as withdrawals from the pipe system decrease.           

Srinivasan presented her recommendations to Chennai’s policymakers in June 2008 and plans to approach NGOs, development banks, and civic groups in the future. “I am not offering a silver bullet, rather an analytic framework to think about the problem,” she says. “Eventually, I hope it will make its way into influencing policy decisions.”        

Nate Sulat was a writer-intern at the Woods Institute for the Environment in summer 2008.