Central Valley

Season off to good start as storms feed reservoirs

What a difference a year makes for water supply. Battered by November storms, the growing Sierra Nevada snowpack and major reservoir storage haven't looked this healthy in at least four years.

Only a year after experiencing an extended drought, the state is starting to prepare for possible flooding.

"The November storms have saturated the soils and streams are flowing again," said state hydrology chief Jon Ericson, based in Sacramento. "It's quite a start."

But water experts know the season could turn dry very quickly. That would mean less water for east Valley farmers and probably additional water cutbacks for west-side growers who face limited water deliveries come rain or shine.

West-siders get water from Northern California rivers. The water must pass through the troubled Sacramento-San Joaquin Delta, where water pumping has been limited to protect dying fish. A wet year would boost their water supply, but even then farm officials still expect below 60% of contractual allotments.

This year, storms already have been influenced by La Niña, a powerful Pacific Ocean phenomenon. It often steers storms to Northern California while leaving Southern California dry.

Unfortunately, the forecast is a coin-flip for the state's multibillion-dollar farm belt in the San Joaquin Valley -- sometimes wet, sometimes dry. Thousands of farmers here depend upon the San Joaquin and Kings rivers for irrigation water.

Fresno's rain total for the season is 2.24 inches -- slightly above average, thanks to the November storms.

A storm this weekend will pass through Northern California, but it may not rain much here, says Kevin Durfee of the National Weather Service in Hanford. That looks like La Niña's pattern, he said.

"We've been getting strong storms the last few weeks, and that's not unusual," he said. "But it could dry out. There's just no statistical way of forecasting that kind of trend."

If Northern California has a big winter, more water would be available to pump into San Luis Reservoir in western Merced County where many west-side farmers get federal water.

But if pumping is restricted to protect dwindling delta smelt and salmon, farmers may still get far less than they would like to buy, said Dan Nelson, executive director of the San Luis & Delta-Mendota Water Authority.

The restrictions typically begin around Christmas and can continue until late June, he said.

"At some point, it doesn't matter how much more it snows in Northern California," he said. "It's how much water we can move through the delta."

Nelson, who represents 29 water agencies, said his west-side farm customers need the water for 1.2 million acres of crops. Last year, they got only 40% of the water they wanted to buy even though the state had drought-busting storms.

In early December last year, it looked like they might get much less than 40%. Statewide, reservoirs were 70% of average. Shasta Reservoir -- the largest reservoir in the state -- was only 36% of average.

The snowpack statewide was 42% of average. A few November storms dropped light snow, setting the stage for a fourth drought year in California.

But a warming Pacific Ocean -- called El Niño, the flip side of La Niña -- came to the rescue just before Christmas, creating conditions that shifted the high-elevation jet stream to steer storms into California.

The state had its first average water supply in three years. Farmers in many parts of the Valley could stop pumping underground water and use river water again. Waterfalls flowed in Yosemite National Park. The drought seemed to fade.

For flood control purposes, officials are watching reservoir levels to make sure they don't rise too high early in the season. If they need to, they will release water from reservoirs so there will be enough room to capture runoff from big storms or snowmelt.

Meanwhile, out in the Pacific, El Niño abruptly departed in late spring, followed by an unusually fast ocean cool-down along the equator.

Federal long-range forecasters soon began talking about La Niña, raising worries of another dry winter in the Valley.

But this year, there's a little more water in reservoirs.

Pine Flat Reservoir on the Kings River has more than 400,000 acre-feet of water, compared to only 284,000 at this point last year, said Ed Dittenbir, hydrographer for the Kings River Water Association.

"It's a great start to the season," he said. "But everybody knows we have a long way to go from here."