Rain welcome, but no drought buster
By: Dave Downey

The burst of rain over the holidays left the region with more moisture than it usually receives at this point in the winter, but that hasn't dampened the likelihood area residents will face severe water-use restrictions this summer, officials say.

Not only that, Southern California's largest provider says rationing is more likely now than it was a few months ago.

Due to the recent string of dry years and a new federal report on an endangered fish, the chance rationing will occur has gone from 1 in 3 to 1 in 2, said Steve Arakawa, water resources manager for Metropolitan Water District, in a telephone interview this week.

Metropolitan is a wholesaler that pipes water from the Sierra Nevada and Rocky Mountains to agencies that serve nearly 20 million people from Santa Barbara to the U.S.-Mexico border, including San Diego and Riverside counties.

Consequently, local officials continue to urge residents to conserve water and turn off sprinklers for at least a week after it rains.

"The bottom line is, it (the rain) hasn't made any material change," said John Rossi, general manager for the Western Municipal Water District, which serves a 500-square-mile swath of western Riverside County populated by 800,000 people. "We're marching ahead, planning for rationing, while hoping beyond hope that we get a whole lot more snow."

Likewise, Bob Yamada, water resources manager for the San Diego County Water Authority, which distributes water to cities and agencies throughout San Diego County, said the better-than-average rainfall hasn't ended the threat of rationing.

"It's still a very strong possibility," Yamada said.

Not in our backyard

Bob Muir, a spokesman for Metropolitan in Los Angeles, maintained that officials are not exaggerating the threat; while it may be wet here, there's been lower-than-normal rainfall in places that feed the region's supply.

"We can't look at our own backyard to see how our water supply is coming along because it comes from hundreds of miles away," Muir said.

Southern California is a semi-arid region that doesn't get close to enough rainfall to support its huge population.

Instead, the region has to rely on water piped in from the Sierra Nevada mountains via the State Water Project and from the Rocky Mountains via the Colorado River and a desert canal. Those sources combine to provide more than three-fourths of San Diego County's water and more than 60 percent of western Riverside County's water.

"We haven't jumped the gun on this," Muir said. "Otherwise, we would already be in reductions, which would lead to mandatory rationing."

Instead, Metropolitan is waiting until March or April to decide whether to slash cities' allocations, he said.

"We're going to hold off until the last possible second," he said. "We understand that there is a certain amount of pain that comes with mandatory rationing."

Rationing may be on the horizon even though area rainfall totals are well ahead of where they typically are at this time of the year.

Ramona has received 7.13 inches of rain, well above its season-to-date average of 4.85 inches, said Brandt Maxwell, a forecaster for the National Weather Service in Rancho Bernardo. And Oceanside Municipal Airport has recorded 5.12 inches of moisture, about 2 inches above normal.

A total of 7.49 inches of rain has fallen at Temecula, more than 2 inches in excess of the norm, according to Temeculaweather.com.

But hundreds of miles away, the snow in the Sierra Nevada is only three-fourths as deep as it should be in early January, according to the California Department of Water Resources.

The fish factor

Making matters worse, climate scientists say the West is moving into a La Nina weather pattern characterized by cooler-than-normal waters in the equatorial Pacific. The pattern usually causes storms to skip Southern California. It was La Nina that in 2008 triggered an unusually early end to the last rainy season.

Local officials worry that Mother Nature's faucet will turn off abruptly again in 2009, well before the season concludes in April.

Compounding weather concerns are changing rules for protecting imperiled fish.

The U.S. Fish and Wildlife Service issued a report last month outlining measures to protect the tiny delta smelt that lives in the Sacramento-San Joaquin Delta.

That report has huge implications because the Sierra water headed for Southern California is piped south through the delta. That new federal "biological opinion" sets in stone ---- and expands on ---- temporary restrictions ordered by a federal judge in 2007.

Under the new restrictions, up to half of deliveries through the State Water Project, the giant system of 700 miles of canals and pipelines and 21 reservoirs that pushes water south, will be halted.

Then, in March, federal officials are expected to unveil a similar plan to reverse declining populations of salmon and steelhead trout. That could trigger more delta pumping restrictions, said Metropolitan's Arakawa.

Exactly what the developments will mean isn't known, but the situation looks grim. Metropolitan was told in November it may receive no more than 285,000 acre-feet in 2009.

By comparison, the region received much more water ---- 700,000 acre-feet ---- last year from the State Water Project, Arakawa said.

An acre-foot is about 326,000 gallons, or the amount it takes to cover a football field a foot deep. It is enough to supply two families for a year.

Arakawa said Metropolitan's allocation could increase if a lot more snow falls in the mountains. But in any event, Southern California isn't likely to get as much as it did last year.

There is some good news: Metropolitan expects to receive a full allocation from the Colorado River, or 900,000 acre-feet, he said.

Colleen Dwyer, a spokeswoman for the U.S. Bureau of Reclamation in Boulder City, Nev., said it helps that the drought in the Rocky Mountains may be easing. So far this winter the Rockies have received more snow than usual, Dwyer said.

Still, as the river's reservoirs wait to be filled by melting snow, they are starting out at their lowest levels since the 1960s, Dwyer said.

"It would take several years of above-average rainfall to help us recover from 10 years of drought," she said.