The state’s proposal to restore habitat in the Delta and build two massive water diversion tunnels on the Sacramento River “falls short” in its scientific rigor, according to a new report by a group of scientists.
The tunnels are just one component of the Bay Delta Conservation Plan, a $25 billion project proposed by the California Department of Water Resources. The project, intended to reform water management in the Sacramento-San Joaquin Delta, has been in the works for eight years. It is now undergoing public review, with a decision on approval expected by the end of this year.
As part of that process, legislation in 2009 required the draft environmental impact study for the project to be reviewed by the Delta Independent Science Board, a 10-member panel of technical experts appointed by the Delta Stewardship Council. The council is a state agency, separate from DWR, whose seven members are appointed by the governor and Legislature. It has limited powers of review over the Bay Delta Conservation Plan and other matters in the Delta.
In a 133-page report released Monday, the Independent Science Board commends the BDCP planners for compiling and analyzing mountains of complex information on the Delta, the largest estuary on the West Coast of the Americas. But it also faults the analysis in a number of crucial areas, including interaction among wildlife species, effects of climate change, effects on San Francisco Bay, poor analysis of uncertainties, and poor organization that undermines public understanding.
Never miss a local story.
Jay Lund, the science panel’s chair-elect and a professor of civil and environmental engineering at UC Davis, said another issue is the way the proposal analyzes the effectiveness of 100,000 acres of habitat restoration proposed in the Delta.
“One of the bigger concerns in my mind, and for the science panel, is that they’re assuming the restoration is going to work, and work right away,” said Lund.
The panel found that assumption to be faulty. Yet a lot hinges on it in the overall plan.
For instance, the plan strives to meet so-called “co-equal” goals to improve water reliability and to restore wildlife species, including native fish such as endangered salmon and Delta smelt. It intends the habitat restoration to offset some of the harmful effects of the proposed water diversion tunnels. Those goals will not be successful if the habitat restoration doesn’t work.
Nancy Vogel, a spokeswoman at the California Department of Water Resources, said officials appreciate the science panel’s work but have not yet had a chance to review the entire report.
“This type of rigorous, independent scientific review will ultimately help improve outcomes for BDCP,” Vogel said via email.
The Delta is a vital water supply for much of California, providing fresh water to 25 million people and more than 3 million acres of farmland. All that water is diverted today by state and federal pump and canal systems in the south Delta, near Tracy. Yet that water demand has helped pushed the estuary to the brink of ecological collapse. Numerous native species are thought to be on the verge of extinction, and water quality problems are an ongoing concern.
The Bay Delta Conservation Plan aims to re-engineer the estuary by moving the diversion point upstream. It calls for two tunnels, 40 feet in diameter, fed by three giant new water intakes on the Sacramento River near Courtland. This would alter the present flow of fresh water, but is claimed to be less harmful to native fish than the present system.
The tunnels and pumps would be paid for by water agencies from San Jose to San Diego that benefit from the project. They, in turn, will pass the cost along to ratepayers. The habitat restoration is proposed to be funded by state and federal taxpayers.
The science panel’s advice has no regulatory effect on the project. The Delta Stewardship Council will use the report to formulate its own comments about the Bay Delta Conservation Plan, which also will have no regulatory effect. But the science review is likely to spark fierce debate over whether the controversial project should proceed.
“They are a collection of leading scientists from around the nation who are really up on the kinds of issues that this (project) would touch on,” said Keith Coolidge, the council’s manager of external affairs. “I think their opinion will carry great weight with the council and, I hope, with the public.”
The council will discuss the report at its May 29 meeting in Sacramento.