Bay Area users of the Tuolumne River cut their water use by 18 percent between late January and early March, managers of the system said.
The voluntary savings exceeded the 10 percent goal set by the San Francisco Public Utilities Commission and the 26 wholesale agencies that it supplies in three other counties. Continued conservation could stave off mandatory rationing if the drought persists, a city news release said.
About 2.6 million people get some or all of their water from San Francisco’s Hetchy Hetchy Water and Power System. About 85 percent of the system’s supply comes from the Tuolumne and the rest from smaller Bay Area watersheds.
San Francisco had sought in 2012 to buy water from the Modesto Irrigation District to provide a dry-year backup, but the idea died in the face of protests about possible shortages for Modesto-area farmers and domestic users. The water, about 1 percent of the MID’s usual supply, would have sold for about 70 times what its farmers paid that year.
San Francisco has talked about a similar deal with the Oakdale Irrigation District, an active player in the water market in recent years, but the OID is not selling this year.
Environmental groups, including the Tuolumne River Trust, have urged San Francisco to promote conservation instead of increasing river diversions.
The 18 percent drop in Bay Area consumption came in the winter, so it does not involve much outdoor water use. Still, customers have an advantage in keeping up their frugal ways, because summers there are cooler and yards are generally smaller than in Stanislaus County.