Delta Blues

By Erin Hallissy

Professors examine how water shortages could affect the East Bay Economy

The Sacramento–San Joaquin delta has dozens of man-made islands that are at risk of flooding, like the one seen here, because of deteriorating levees.



The Sacramento–San Joaquin River Delta is a remarkable ecosystem. Once a tidal freshwater marsh — the West Coast’s largest estuary — it was shaped decades ago into a complex system of 55 man-made islands surrounded by levees to protect them from floodwaters.

The delta provides drinking water to two-thirds of Californians and irrigation water for millions of acres of crops in the Central Valley. It is so vital to California’s daily life that it has long been a political battlefield, with Northern and Southern Californians and agricultural giants fighting over water rights and how to deliver water. Environmentalists and government officials have pushed to protect the increasingly threatened ecosystem and its endangered fish species.

With more than half of the East Bay getting water either from the delta or carried in pipelines through it, the Contra Costa Economic Partnership commissioned a study by Saint Mary’s College’s Center for the Regional Economy on the economic impacts of disruptions in the water supply to the region. Disruptions could include a limited or extended drought, such as those that struck Northern California in 1976–77 and 1987–92, or a catastrophic failure of delta levees.

Saint Mary’s economics professor Richard Courtney, earth sciences professor William Perkins and business administration professor William Halpin surveyed the region’s water districts to see how water is distributed and used by business and residential customers. They found that while there is enough water to meet demands if there is normal rainfall over the next 25 years, just one severely dry year could mean rationing for customers of the East Bay Municipal Utility District (EBMUD).

Local districts have prepared for shortages, Courtney says. Zone 7 in eastern Alameda County banks emergency supplies by sending water to Kern County that can be returned when necessary. The Contra Costa Water District (CCWD) in the late 1970s built Los Vaqueros Reservoir, which holds a three-month emergency supply. EBMUD has reservoirs east of the delta and in Contra Costa County. But many businesses that the Saint Mary’s team contacted either didn’t respond or seemed not too worried about supply disruptions.

“Water is important, but it’s not at the top of anyone’s list of most important issues,” Courtney says. “Many businesses need water. They take access to adequate supply of water for granted.”

Bob Whitley of the Contra Costa Council’s Water Task Force says the study is important because “there has not been any type of integrated or comprehensive view of what the water supply issue means to the East Bay.”

“Not many view water as an essential component to the metropolitan area because of the different service areas,” he says. “Those who live in the East Bay MUD only know about East Bay MUD. But the East Bay regional economy doesn’t know the water district boundaries. What happens in Fremont does affect what happens in Walnut Creek.”

EBMUD gets water for its 1.3 million customers from the Mokelumne River, but some of its pipelines go through the delta. CCWD, which serves more than 550,000 customers in north and east Contra Costa County, pumps water directly out of the delta. The other surveyed district in addition to Zone 7 is the Alameda County Water District in the Fremont area.

The Saint Mary's study looked at potential water shortages in these four East Bay districts. Click photo to enlarge.

The perfect system

The Bay Area has a Mediterranean climate, with wet winters and dry summers. Perkins says winter snows in the Sierra Nevada that melt in the spring swell rivers, reservoirs and the delta with runoff that can be used during the arid summer and fall.

“This is the perfect system,” says Perkins, director of SMC’s Environmental Science and Studies Program. “With no rain in the summer, we look to the Sierra and say ‘thank you — melt, and we can drink.’ ”

However, man’s interference with the delta, including the aqueducts that send its water to other parts of the state, has threatened its stability and its normally ample supply of freshwater.

Most deltas form in the sea, where sediment settles beyond the river’s mouth. But the Sacramento and San Joaquin rivers, which drain nearly half the state’s watershed, formed their delta inland, possibly because the estuary quickly becomes a channel from Antioch to Richmond that separates the freshwater flows from the saltwater San Francisco Bay and the narrow Golden Gate that leads to the Pacific Ocean.

More than 100 years ago, as California attracted settlers after its gold mines were spent, farmers started planting crops in the delta’s rich peat soil, and built levees — eventually stretching to 1,600 miles — to protect their land from flooding. Gradually, the light soil compressed or blew away, and all 55 delta islands created by the 1930s are now sinking behind the levees. Some islands — where asparagus, corn, strawberries, pears and dozens of other crops thrive, along with an increasing number of houses — are as low as 25 feet below sea level. When a levee breaks, water rushes into the island, filling it like a bathtub.

“Agriculture is the cause of many, many things out there,” Perkins says. “Farmers built their own levees around their own islands, and some of them are good, and some of them aren’t.”

Fragile levees

Even before Hurricane Katrina caused massive levee breaks in New Orleans in 2005, California water officials warned that delta levees were “a ticking time bomb.” Many are maintained by private reclamation districts and do not meet government safety standards.

An earthquake could trigger levee breaks, but more commonly levees fail during heavy winter storms. During El Niño-fueled deluges in early 1997, more than 50 levees failed in the delta and surrounding regions, killing eight, forcing the evacuations of more than 100,000 people and damaging or destroying 24,000 residences.

Yet poorly built and maintained levees can collapse at any time and in a variety of ways. In 2004, a levee on the delta’s Jones Tract disintegrated on a sunny summer day, creating a lake larger than CCWD’s Los Vaqueros Reservoir, threatening water quality and endangering several EBMUD pipelines that traversed the island.

Large levee failures can allow saltwater to push from the Bay into the delta, creating health risks for people whose drinking supply is drawn there, including those in the CCWD or parts of Los Angeles. Droughts also lead to saltwater intrusion because of the lack of fresh water from rain or snow.

When supplies shrink

According to the SMC study, CCWD is experiencing more rapid growth in its service area than other East Bay water districts, making its water supply from the delta even more critical over the next 25 years. Disruptions could occur from a drought lasting two or more years, or from global warming, which could reduce snowpack and create higher temperatures that would drastically increase water demand.

Perkins and Courtney note that the demand for water is growing, but there is a finite supply. That may require more conservation, market-based pricing, and the development of alternative supply methods, such as desalination. In past droughts, rationing was imposed, and before heavy rains this winter, some districts were already warning that cutbacks were possible.

If there is not enough water to meet demand, residential customers — who use two-thirds of the region’s water — will be most affected. The most drastic impact could be on yards and gardens, since 40 percent of water goes to exterior use, Courtney says. The brown lawns of the mid-1970s would undoubtedly return, and residential landscaping businesses, along with nurseries and garden centers, could take a big hit.
Some East Bay oil refineries, which use water in boilers and condensers, told the SMC team that they could deal with short-term water disruptions through conservation and increased use of reclaimed water. For a longer shortage of three years with 35 percent less water, they said they would buy equipment to desalinate seawater. The professors report that that could cost the four refineries in Contra Costa County an estimated $168 million in increased capital expenditures.

Hospitals also reported they would struggle with significant long-term supply problems. One reported that it would have to relocate patients and curtail admittances and surgeries.

Not every type of business said it would be impacted by water shortfall. A vineyard and winery said it could increase conservation efforts and rely on more well water. However, most people and businesses would probably need to make cutbacks if supplies were disrupted.

“We’re really dependent on the delta here,” Perkins says. “We really do need to protect it.”