Two out of every three Californians get at least some drinking water from the Delta. In a state of 37 million people, one in every four gallons of water consumed by the state's farms, factories and people comes from the Delta.
And California's population is expected to climb to 48 million by 2030.
Meanwhile, the state's use of its second-largest water source, the Colorado River, is being curtailed as upstream states and the federal government begin to more strictly enforce the 1922 interstate treaty that limits California's share.
CalFed promised water agencies in the San Joaquin Valley and Southern California that they would be better able to rely on the Delta to provide the water they need.
But water managers say the CalFed program adopted five years ago has failed to deliver.
"Water supply reliability out of the Delta -- I don't think you could make the case that CalFed has improved that," said Steve Hall, executive director of the Association of California Water Agencies, which represents nearly all of the state's urban and agricultural water agencies. "Ultimately, we have to be able to export water more reliably out of the Delta without necessarily increasing the amount."
That effort suffered a blow early this year when scientists confirmed a dramatic decline in Delta fish populations. Pumps that siphon water out of the Delta could be contributing to the decline, although there are other possible causes.
Environmentalists, however, say CalFed already is allowing more water to be pumped out of the Delta than ever before.
Environmental Defense has compiled figures to show that 6.4 million acre-feet were pumped out of the Delta this year, a record high set in the middle of a major fish crisis. Three of the four highest rates of pumping in the Delta have occurred in the past four years, according to the national environmental organization, which has offices in Oakland.
"We have the lowest Delta smelt population ever, and the highest export levels ever," said Spreck Rosekrans, a senior analyst and author of a recent report called "Finding the Water," which describes how the amount of water dedicated to environmental purposes in CalFed has diminished since the agreement was adopted in 2000.
Water agencies say there is no direct statistical relationship between fish populations and annual pumping volumes.
Still, the fish crisis came as a troubling setback to water users who were counting on CalFed's ecosystem restoration projects to improve environmental conditions enough to relieve restrictions on their ability to take more water out of the Delta. When fish populations are healthy, there is less pressure to reduce water deliveries than when the environment is highly degraded.
"Look at the amount that has been spent on ecosystem (about $800 million) against surface storage and conveyance (less than $240 million)," said former Secretary of State Bill Jones, an early CalFed negotiator and advocate of San Joaquin Valley farmers.
Jones and others are frustrated at the apparent failure of CalFed's environmental work to improve the Delta environment and its lack of progress on building a large new reservoir.
The last major dam, New Melones Dam, was completed in 1979, when the state's population was less than 24 million.
Since then, California has grown by 50 percent and is on pace to double its 1979 population by 2030.
CalFed has spent more than $1 billion on ground water storage, boosting capacity in underground aquifers by 300,000 acre-feet, mostly in the southern San Joaquin Valley.
But the trend in surface storage is for individual water agencies to build smaller, regional reservoirs, such as Contra Costa Water District's 100,000 acre-foot Los Vaqueros Reservoir completed in 1998 and the Metropolitan Water District of Southern California's 800,000 acre-foot Diamond Valley Reservoir completed in 1999.
Perhaps more than storage, water agencies south of the Delta want to increase the capacity of the largest water pumps in the state.
The State Water Project pumps near Tracy move water out of the Delta and into a 444-mile aqueduct that ends in Riverside County. By regulation, those pumps are allowed to run only at about two-thirds throttle.
The water agencies badly want to ease those restrictions. They say doing so would allow them to slow pumping down for environmental reasons -- such as when fish schools move near the intakes -- if they could crank the pumps harder later, when it's safe.
Environmentalists, Delta farmers and anglers are mistrustful of that plan, however, and say the Delta's recent woes could be caused, at least in part, by pumping. Therefore, it would be irresponsible to move forward with the relaxation on pumping limits now, they say.
State water officials are navigating a middle ground, moving forward with plans that will set the stage for increasing the pumping capacity without committing to a final decision on whether to follow through with higher pumping rates.
A Delta agricultural district, the South Delta Water Agency, is among those critics who say CalFed is committing prematurely to higher pumping rates.
In a Dec. 7 letter about wide-ranging negotiations among CalFed participants, the district's lawyer complained that CalFed has defanged environmental regulators who might otherwise order reductions in pumping.
"There is purposefully no one effort to identify the effects (of state and federal pumps) on fisheries and require appropriate mitigation which may include decreased exports," wrote the South Delta agency's attorney, John Herrick.
"The CalFed process of working toward consensus has co-opted the fishery agencies into being supporters of ever-increasing exports, a subject on which they should be neutral," Herrick added.
Mike Taugher covers natural resources. Reach him at 925-943-8257 or firstname.lastname@example.org.