Los Angeles officials urged residents Wednesday to reduce water consumption by 10% as weather forecasters predicted the region's historic dry spell will combine with a summer of record-setting temperatures.
Mayor Antonio Villaraigosa's call for conservation -- the first water-reduction goal the city has issued in more than a decade -- comes as water agencies across Southern California are trying to deal with the driest season on record.
The Metropolitan Water District of Southern California, which supplies water to communities across the region, immediately backed the mayor's conservation push, and officials said they hope residents in the rest of Southern California will follow suit.
The agency has embarked on a large water conservation campaign inspired not only by little rainfall but also by unusually small snowpack in the eastern Sierra Nevada and continued drought along the Colorado River basin, which are two key sources of water.
Adding to the uncertainty is the state's decision last week to temporarily halt water pumping to the Southland from the Sacramento-San Joaquin Delta in an effort to protect an endangered fish.
Jeffrey Kightlinger, the water district's general manager, said that if dry conditions continue, the agency may consider steps such as greatly reducing the amount of water delivered to agricultural businesses and increasing their rates next year.
"We have unprecedented dry conditions," Kightlinger said. "We know the Colorado River is going to be dry next year. And we have the problems with this [Delta fish] species. So we could be losing water from both the Colorado River and the State Water Project going into next year."
That could mean more aggressive conservation efforts, including mandatory rationing -- something that hasn't occurred in Southern California since 1991.
The region imports about half of its water. The rest comes from local underground aquifers, which are still in reasonably good shape thanks to the 2005 rainy season, which was the second-wettest on record.
Those reserves are giving Southern California some wiggle room this summer, officials said. But if the dry conditions continue, the future is expected to be uglier.
"If we have another dry year next year, and even the year after, we'll really feel the impact as far as the water supply," said Jayme Laber, a hydrologist for the National Weather Service in Oxnard.
Forecasters offer no reassurance. A so-called La Nina condition is forming in the Pacific Ocean, suggesting dry, warm conditions could continue into next year, they said.
"With this late developing La Nina, that's not good for Southern California or the Colorado River Basin," said Bill Patzert, a climatologist for the Jet Propulsion Laboratory in La Canada-Flintridge. "It could be dry next winter as well."
(Since July 1 of last year, downtown L.A. has recorded less than 4 inches of rain).
Patzert and others also said this summer is expected to be as hot, if not hotter, than last summer, during which several record-breaking heat waves were blamed for the deaths of more than 100 people across the state.
Even if the dry spell continues, water officials said, Southern California is in better shape now than during the drought of the late 1980s and early 1990s.
Back then, officials ordered mandatory conservation, requiring a 15% cut in water use.
The L.A. City Council, for example, passed an ordinance that prohibited lawn watering during the middle of the day, automatic serving of water in restaurants and hosing down sidewalks.
A crew called the "drought busters" went around the city issuing citations to water customers who violated the ordinance.
Since that drought, water agencies have worked to improve reserves and better tap groundwater supplies. In addition, many residents have taken steps to conserve, including purchasing more water-efficient toilets and washing machines.
"Hopefully if we're all doing our job right, we've planned for this. We won't go under in one dry year," said Gina DePinto, a spokeswoman for the Orange County Water District.
Water officials have been saying for months that the region could face several years of drought conditions.
The mountain snowpack vital to water imports from Northern California is at its lowest level in nearly two decades. Several big reservoirs in the Colorado system are half-empty.
L.A. officials didn't suggest to residents specific ways to reduce water consumption.
But in general, water agencies recommend taking shorter showers, fixing leaking faucets, using a broom rather than a hose to clean driveways and installing water-conserving sprinklers.
"Los Angeles needs to change course and conserve water to steer clear of this perfect storm," Villaraigosa said. "The combination of record-low rainfall, the second-lowest snowpack ever recorded and a potentially very hot summer is a perfect storm that could put Los Angeles into a drought."