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Water Supplies Still Not Normal

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Times Staff Writer

This year may set records for the most rain, but it won’t be enough to reverse the impact of five years of drought on Southern California’s water supplies, weather experts and water officials said Wednesday.

Local supplies have improved greatly. All 27 of Los Angeles County’s groundwater collecting basins are filled to capacity, the county’s Department of Public Works said. Similarly, the Sierra Nevada snowpack -- an important source of water for the region -- is 40% above normal this season.

But the Colorado River reservoirs remain far below normal levels. About 70% of the water used in Southern California is imported from the river as well as from the California Aqueduct in Northern California and the Sierra Nevada, said Denis Wolcott, a spokesman for the Metropolitan Water District.

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William Patzert, a meteorologist at the Jet Propulsion Laboratory in La Canada Flintridge, said that although Southern California has had much heavier rain than usual, the upper Colorado River Basin continues to suffer from a prolonged drought. It has received less rain than Los Angeles.

Lake Mead and Lake Powell, which are fed by the Colorado River, remain at only about 59% and 34% full, respectively, said Debra Man, chief operating officer of the Metropolitan Water District, which manages the distribution of water to a plethora of districts serving 18 million people in Southern California. For the first time since 1999, hydrologists in the upper Colorado River Basin are predicting near-normal water flows into Lake Powell, one of the West’s biggest reservoirs.

Lake Mead’s storage level, however, is expected to drop, in part because of water releases to keep the Colorado River flowing to protect fish and habitat, said Wolcott.

Meteorologists and others said that the Colorado River region has suffered through years of drought conditions, and that one wet year won’t bring water levels back to normal.

“This is the kind of year people have been asking for, and they’re getting more than they bargained for,” said Kelly Redmond, regional climatologist for the Western Regional Climate Center in Reno. “But when you’re in a deficit, it’s hard for water managers to turn water down.”

Bob Walsh, spokesman for the U.S. Bureau of Reclamation in Boulder City, added, “Most hydrologists would tell you that one good year does not make up for five bad years.”

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Closer to home, the wet weather is making a significant difference.

The storms have encouraged conservation by reducing water demand for such activities as landscaping and washing cars. According to the Department of Water and Power, demand has been slashed by 25% because of the rainfall as people turn off their automatic sprinklers.

If Southern California requires less imported water this year, that might allow officials to begin building up reservoirs, including Lake Mead and Lake Powell.

“All in all, it’s adding up to a really strong water supply year,” Walsh said.

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(BEGIN TEXT OF INFOBOX)

Lots of rain, but drought persists

An unusual weather pattern caused by persistent high pressure over the Gulf of Alaska has drenched most of California this year, but the storms have not fully offset years of previous drought.

The rain wouldn’t stop . . .

1. Dry high-pressure system -- “blocking high” -- slides north.

2. Arctic jet stream forms an oval shape around the high.

3. A wet low-pressure system gets cut off from the jet stream.

4. With no wind to drive it east, the low stalls, spinning rain ashore for days.

But the drought isn’t completely gone

California’s snowpack is the heaviest it has been in 10 years, but some areas, including the Klamath Basin of Oregon and the Upper Colorado River Basin, remain under drought conditions.

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Snowpack

*--* Water content, % of normal % of yearly Region in inches year-to-date total average* Northern Sierra 27.90 119% 99 Central Sierra 34.50 124 101 Southern Sierra 33.20 160 126 Statewide 32.30 135 110

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*April 1 is the date of normal maximum accumulation for the season.

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Key reservoir storage in California

*--* Reservoir River % of average % of capacity Trinity Lake Trinity 90 67 Shasta Lake Sacramento 94 67 Lake Oroville Feather 78 56 New Bullards Bar Res Yuba 92 57 Folsom Lake American 111 61 New Melones Res Stanislaus 101 58 Don Pedro Res Tuolumne 118 81 Lake McClure Merced 103 53 Millerton Lake San Joaquin 114 75 Pine Flat Res Kings 77 41 Isabella Kern 81 24 San Luis Res (Offstream) 111 94

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Graphics reporting by Joel Greenberg and Pat Rathbun

Sources: William Patzert, Jet Propulsion Laboratory; accuweather.com; theweatherprediction.com; National Oceanic and Atmospheric Administration; Rich Tinker, NOAA Climate Prediction Center

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