Wet Season Raises Hopes of More Water

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Snowpack High

As of January 3, the Northern statistical mountain snowpack was measured at 174 percent of average while the Central section held 198 percent of average snowpack and the Southern section held onto 277 percent of its average snowpack.

The statewide mountain snowpack average is about 212 percent of normal, providing a stream of snowmelt throughout the warmer months that will replenish the state’s reservoirs.

One such reservoir is Lake Oroville, which depends heavily on spring and summer snowmelt for recharge, and has not reached its 3.5 million acre-foot capacity since 2003.

Reservoir Levels

Heavy rains have also refilled reservoirs around the state, bringing levels above 100 percent of seasonal average in many cases.

Oroville, the main reservoir of the State Water Project (SWP), is already at 99 percent of normal, holding more than 2.22 million acre-feet of water. Lake Shasta, the main reservoir of the Central Valley Project (CVP), is at 118 percent of normal, with more than 3.45 million acre-feet of water. Folsom Lake, also part of the CVP system, is at 86 percent of normal with about 415,950 acre-feet of water.

The positive news follows several consecutive years of below-average precipitation and ongoing drought conditions. In response, the SWP and CVP dramatically reduced water allocations in 2008 and 2009 to as low as 15 percent of normal.

The economic harm was unmistakable when these shortages were combined with pumping restrictions stemming from environmental concerns, as Central Valley farmers were forced to fallow crop land and unemployment reached as high as 30 percent in some rural counties.

Water Allocations

The Department of Water Resources (DWR) issued a press release on Dec. 28, 2010, just days after the official start of the winter season, indicating that water allocations could climb above 50 percent of requested deliveries depending on "weather between now and spring."

With the rainy season theoretically in its beginning, there is significant hope that supplies will edge closer to meeting demand around the state.

"This boosts our hopes that we will have an adequate water supply for our cities and farms as we continue to shake off effects of the 2007-2009 drought," said DWR Director Mark Cowin.

Urban users in Southern California have something else to be happy about—precipitation in the Colorado River Basin is at about 150 percent of average for this time of year, allowing exports to increase and reservoirs along the river to refill.

California’s largest water agency, the Metropolitan Water District of Southern California (MWD), presently holds more than 1 million acre-feet annually in prioritized water allocations from the Colorado River.

Due to a complex interstate and international agreement that includes seven U.S. states and Mexico, the contentious politics around use of Colorado River resources can result in MWD receiving only about 550,000 acre-feet of water or less in dry years.

Weather Patterns

Still, water supplies in California are notoriously volatile given the ratios of average demand to average supply and the unpredictable weather patterns upon which the entire water economy relies.

"We’ve come to realize that not only are California’s winters very variable; they can also change very quickly from a significant winter to a so-so winter," said Frank Gehrke, chief of California’s Cooperative Snow Surveys Program. Gehrke has been measuring California’s snowpack since 1981.

"It’s quite a good start," Gehrke said, "but we don’t know how much it’s going to rain through March, especially it being a La Niña this year."

The La Niña effect is associated with cooler-than-normal water temperatures in the Equatorial Pacific Ocean, above-average precipitation in the Pacific Northwest and drier conditions in the Southwest. Predicting the effects on Northern California is difficult.

Even as reservoirs continue to fill high relative to yearly averages, many remain quite low in absolute terms—consecutive years of dry weather depress average reservoir levels, artificially biasing water measurements upward, creating mistaken perceptions about the amount of water available for use.

Drought Executive Order

As of former Governor Arnold Schwarzenegger’s last day in office on January 3, no declaration signaling an end to the drought was declared. An official end of the drought begun via Executive Order S-06-08 would require newly sworn Governor Jerry Brown to issue another executive order to end it.

"Our situation when it comes to water is so precarious that we should probably remain in a drought situation until we can figure out how we can better deliver water to the entire state," said Sandy Cooney with the California Natural Resources Agency.

Water Bond

The Legislature and the Governor won a hard-fought victory in 2009 to place on the ballot an $11.1 billion bond that would have provided for construction of new storage and conveyance facilities. Last year, however, lawmakers pulled the bond measure off the ballot, opting to take it to voters in 2012 due to political concerns.

"After discussion with the Governor and legislative leadership, it was kind of the consensus, given the contentious political climate over the budget and a lot of other political issues floating around...to wait until the message on the water bond could be heard by voters," said Jim Earp of the Alliance for Jobs, a coalition of contractors and construction workers.

Action on water is still needed, as reservoirs continue to drain slowly. In absolute terms, Lake Oroville is at only 63 percent of its maximum capacity, even while that figure represents 99 percent of its annual average.

Water managers use the two very different statistical measures—percent of capacity and percent of average—for perspective and context in their analyses. Reservoirs rarely fill to 100 percent of capacity.

Lake Shasta remains at only 76 percent of its 4.5 million acre-foot capacity, while Folsom Lake is at only 43 percent of its 977,000 acre-foot capacity.