By Douglas Fischer, STAFF WRITER,
Inside Bay Area
Thursday, October 6, 2005
The Sacramento-San Joaquin River Delta is crashing.
At just about every level in the food web ‹ big fish, little fish, zooplankton, phytoplankton ‹ the ecosystem's wildlife populations are dropping, despite three wet years in a row and hundreds of millions of dollars spent on recovery and restoration efforts.
New findings released Wednesday at a scientific conference in Oakland simply reinforce what scientists have feared: "There's plenty to be concerned about," said Ted Sommer, a biologist in the California Department of Water Resources' Interagency Ecological Program.
The problems come from many angles and affect a region that serves as a key wildlife sanctuary, a fertile farmbelt and a crucial water source for 22 million Californians and a huge chunk of the state's agriculture industry.
Researchers conducting ongoing surveys long have seen great swings in population levels. But until now, big drops have always followed droughts.
These recent drops in fish populations such as delta smelt and striped bass come as the state has enjoyed three consecutive wet years. More puzzling, fish populations in San Francisco Bay have seen no clear decline.
The finger-pointing has centered on three culprits:
-New toxins in the environment such as pyrethoid pesticides, a supposedly safe alternative to older, longer-lasting pesticides. Use has increased 300 percent in the past three years, according to the Department of Water Resources.
-Increased development pressures in the Delta, coupled with changes in how water is exported to Southern California.
-Flourishing non-native invasive species, particularly several species of zooplankton low in the food web that offer fewer nutrients for fish yet crowd out important food sources.
And there is no sign this will turn around soon, experts say, despite nearly $2.5 billion spent so far on efforts to restore the delta.
Water managers acknowledge the problem but caution against
overreacting. There are somepositives. Salmon runs, for instance, are more robust than any time in the past 20 to
40 years, noted Gerald Johns, deputy director of water and planning and management for the Water Resources Department.
That's a result of various environmental gains made through the California Federal Bay-Delta Program, a $9 billion effort to restore the Sacramento-San Joaquin Delta as well as ensure a reliable supply of water for farmers and municipal water users, he said.
"It's way too early to jump to conclusions. ... This is more like 'CSI Delta,'" Johns added.
Others at the Seventh Biennial State of the San Francisco Estuary Conference on Wednesday said the need for action is very clear.
"We've got a problem, especially when you take a long-term look over the next 50 to 100 years," said Jeff Mount, a University of California, Davis geology professor and director of the school's Watershed Center.
Mount was a member of the Reclamation Board, an obscure state agency charged with overseeing flood control that had drawn ire for efforts to check growth in flood-prone areas until Gov. Arnold Schwarzenegger fired all six members last week.
The Delta, Mount said Wednesday, serves as a giant sewer for agricultural runoff, urban effluent and excess power plant heat. The landscape has been completely changed, with massive water works, deeply sunken farmland and increasing urbanization. All that has an effect, he said.
"Changes happen very fast. We're not grappling with or handling this very rapid change," he added. "We will have a collapse of the Delta."
Since 1993, 94,000 new homes, apartments and condos have been built in and around the Delta, said former Rio Vista Mayor Marci Coglianese, a member of the federal Bay-Delta Public Advisory Committee. That's akin to building in the estuary a new Hayward and Fremont ‹ with all the roads, shopping centers, soccer fields, schools and utilities that come with such homes.
San Joaquin County has seen some of the most explosive growth, with Stockton proposing 30,000 more homes in flood-prone areas and Lathrop attempting to build 8,500 homes on a Delta island that flooded in 1997.
Meanwhile, toxic algae blooms are up 10-fold in the past few years. And the fish are disappearing: Delta smelt populations in the past three years are a quarter of the average from the previous five, according to the state. Striped bass is almost nonexistent.
And a change in how water is exported south aimed at protecting fish populations may have unintentionally caused further harm.
Before, more water was pumped south in the spring, when it was plentiful. But the massive turbines also sucked in fish at a particularly vulnerable stage, so water managers switched some exports to summer. Now scientists suspect such a schedule sends too much of the fishes' food supply south.
Yet with no clear culprit, water managers urge caution.
"This is a pretty strong signal," Johns said. But "the worst thing we could do is do something because it makes us feel good."
Contact Douglas Fischer at dfischer@angnewspapers.com