If nothing else, the drought of 2009 is revealing once again how the severity of a drought can vary drastically from one region of California to the next.

It’s not a simple equation. To get an accurate picture of this year’s water situation, one has to take into account annual rainfall, Sierra snowpack and runoff, available Colorado River water, and storage in the reservoirs that serve the State Water Project and the Central Valley Project.

The past two years of less-than-average rainfall are also a crucial consideration. Not to be forgotten is the Endangered Species Act and the endangered status of Delta smelt, which has drastically curtailed the amount of water that can be pumped from the Sacramento-San Joaquin Delta to the urban and agricultural users to the south. 


Consider also your particular region: Where does your water come from? Are you reliant on imported water? Do federal or state regulators control the amount you receive? Do you rely on rainfall, snowmelt, or a combination of both? Are there endangered fish in your watershed?

It’s all part of the complex mosaic of California’s water system, the intricacies of which contribute to a variety of drought-related conditions throughout the state this year

 

With a drenching series of February storms that continued into early March, lakes and reservoirs have begun filling again and the snowpack in the Sierra Nevada is nearing normal levels for this time of the year.

But even a wet February and damp March are not likely to make up for three consecutive years of below-average precipitation and the eighth driest January on record.  The state Department of Water Resources (DWR) this week released its monthly snowpack report and while snow water content is 80 percent of normal, it won’t be enough to call an end to the drought.

“Although recent storms have added to the snowpack, California remains in a serious drought,” said DWR Director Lester Snow. “This year’s precipitation levels are still below average. On the heels of two critically dry years it is unlikely we will make up the deficit and be able to refill our reservoirs before winter’s end. It’s very important that Californians continue to save water at home and in their businesses.”

Not only is snowpack below average statewide, but the February rains have yet to put much of a dent in the deficits of the state’s largest reservoirs that comprise the backbone of the state water system. Elissa Lynn, chief meteorologist with DWR, said snowpack and runoff are key measuring sticks to forecasting water supply. Snowpack accounts for about a third of the state’s water supply.

“The snowpack really does influence everyone in one way or another,” she said.  “It impacts the statewide water supply. It’s such a complicated puzzle. It’s important for people to recognize their water supply and where it comes … people think it’s raining and things are going to be just fine, but their water source may be hundreds of miles away.”

Snowpack and runoff are “really important in determining whether we’re in a drought or a dry year,” said Lynn. “Where the snow is, how much there is and how it flows out … that impacts how our reservoirs fill.”

And this year that picture is not pretty. Lynn said that the “big seven” reservoirs — Shasta, Trinity, Oroville, Folsom, New Melones, Don Pedro and San Luis — are at an average of 46 percent capacity. And projections for this year’s runoff are 57 percent of normal, which follows two subpar runoff years of 53 percent (2006-07) and 58 percent (2007-08). “If you accumulate that kind of deficit,” said Lynn. “That is how you end up in the situation we are in now.”

Chances are if you live in California you will be asked, or required, to cut back on your water use this spring and summer or face penalties if you don’t.  The Association of California Water Agencies reports that 57 of its member agencies are “encouraging” conservation, while 18 have instituted “mandatory” conservation.
Last week, Gov. Schwarzenegger declared a state of emergency because of the drought and encouraged all urban water users to increase conservation efforts and reduce water use by 20 percent.  Some regions have already ordered mandatory rationing. Some areas have already begun rationing and are feeling the effects of the drought:

• In the San Joaquin Valley, farmers in the Fresno area who get water from the Westlands Water District have been told they won’t receive any water from the federal Central Valley Project this year. Normally, they get about 975,000 acre-feet for the roughly 600,000 acres of farmland in the district. Sarah Woolf, spokeswoman for the district, said, “We expect over half of that will not be farmed this year. Considering the economic times we are in, the impact that will be felt will be even greater.”

• Residents in the Sacramento suburb of Folsom have been told they must make 20 percent cuts and perhaps more. They draw their water directly from Folsom Lake, which is at less than 50 percent of its capacity.

• The East Bay Municipal Water District, which serves 1.3 million residents in the S.F. Bay Area, has imposed penalties for customers who fail to reduce water usage by 15 percent. The district’s reservoirs, which draw water from the Mokelumne River watershed, stand at about 60 percent of their maximum storage.

But not all areas of the state are equal when it comes to drought-induced suffering.

In Marin County, the February storms doused fears of water rationing for the 190,000 residents who rely on the Marin Municipal Water District for their drinking water. The MMWD uses a system of local reservoirs to store rainfall and the February storms raised storage from 50 to 79 percent capacity within one month.  “It certainly doesn’t look like there will be any mandatory rationing,” said spokeswoman Libby Pischel. “The storms really helped to fill our reservoirs quickly. We don’t rely on snowpack and we don’t import water from the state. We are fortunate in that we have our own supply.”

The district does rely on the Russian River for about 25 percent of its supplies. The smaller North Marin Water District relies heavily on the Russian River and it finds itself in a much more precarious situation. Deliveries from the Russian River could be cut by as much as 30 percent this year, but this week a decision was delayed until April.

In San Francisco and the Peninsula, water rationing is becoming less and less likely with every storm. That’s because the Hetch Hetchy system, which provides water for 2.4 million people in the Bay Area, is approaching 70 percent of its storage capacity and the outlook continues to improve. “Obviously the storms we have had over the last few weeks have improved our storage situation,” said Chandra Lawrence Johnson, a spokesperson with the San Francisco Public Utilities Commission, which owns and operates the Hetch Hetchy system. “We are still asking our customers for voluntary cutbacks of 10 percent. Our plan is to closely watch the storms through March and decide if we have to go with mandatory rationing. With each storm, our chances of not having to impose rationing improve.”

The Hetch Hetchy system, built in 1923, stores snow runoff and rainfall in a series of reservoirs in the Tuolumne River watershed and sends water via a 160-mile pipeline to the San Francisco Bay Area. It has the advantage of being somewhat of a self-contained system that doesn’t rely on state or federal water projects and does not use the Delta to convey water.

Water users in other metropolitan areas that rely on imported water are at the mercy of the weather and the courts. The Metropolitan Water District (MWD) of Southern California provides water to about half of Southern California. Its 26 member agencies provide water to 19 million residents. The district contracts with the State Water Project for water from Northern California and receives water from the Colorado River via the 242-mile Colorado Aqueduct.

“At this point, obviously, we’re looking at an era of limits on both our sources of supplies,” said Bob Muir, spokesman for the MWD.  The allocation from the State Water Project is expected to be 15 percent of normal, he said. “We’re entering what could be a third dry year and that situation has been exacerbated by environmental situations in the Delta,” said Muir.

He said MWD would rely on its reserves, which include local groundwater and reservoirs. Deliveries from the Colorado could be average this year, after eight of it driest years on record. The percentage of water the MWD uses from each source “is all based on availability,” said Muir.

“I think our situation is really indicative of what is happening in other parts of the state and what other agencies are encountering,” he said. “We’re looking at communities up and down the state that are enforcing mandatory conservation. It really speaks to the complexities and the pervasiveness of the situation. A lot of the problems we’re experiencing are related to what is going on in the Delta. We’re looking for state government to address the Delta problems that are leading to environmental decline and decline of water quality and availability.”

Agencies that contract for water from the State Water Project and the Central Valley Project have been hit with a double whammy, a real drought and what some refer to as a “regulatory drought.” Recent court decisions to protect the Delta smelt have reduced shipments of water to farmers and urban residents south of the Delta. “This year we are in a drought, there is no question,” said Woolf, spokesperson for the Westlands Water District. “But what is really holding us up, because we have had recent rains, are the issues with the Delta. It’s very frustrating.”

On the web:

http://www.acwa.com/

http://wwwdwr.water.ca.gov/

http://www.watereducation.org/

http://www.water.ca.gov/drought/conditions/