Spreck Rosekrans: Dam distraction won't help save Delta

It's the end of a dry year in which a federal court ruled that exports from the Sacramento-San Joaquin Bay Delta, which provide 15 percent of the state's total water supply, must be reduced to prevent the extinction of bellwether endangered fish. The supposed solution is a proposal to spend billions of taxpayer dollars for new surface storage to address both water supply needs and the Delta's environmental woes.

The proposal to build new reservoirs is less than half-baked. Despite vigorous efforts, there is no common understanding of how the reservoirs would be operated, who would pay for the local cost-share portions or how the reservoirs would provide environmental benefits.

The dam debate is a distraction. Our political leaders need to focus on what we must do today, and tomorrow, to save the West Coast's largest estuary and hub of our water supply system. This once-bountiful system is in deep trouble. Increased diversions of freshwater have contributed to a severe decline in the estuary's fisheries that goes beyond the near-extinction of Delta smelt. A collapse of the Delta's fragile and long- neglected levees could devastate the environment and water supply for many Californians, flooding homes and nearby communities.

Much of the rhetorical war Californians see playing out in television advertising and in the Legislature has focused on whether to go forward with taxpayer-funded bonds for three proposed dams: Temperance Flat Reservoir on the San Joaquin River, Sites Reservoir – off-stream but near the Sacramento River – and an expansion of Los Vaqueros Reservoir in Contra Costa County.

The dams proposal does not stand up on its own merit, so the sponsors added it to a bond package that includes worthwhile and important projects.

Many of the more than 1,000 dams built throughout California during the past century have enabled our population and economy to grow, even though many have caused severe environmental harm. However, since the completion of New Melones Reservoir on the Stanislaus River in 1980, large dams have collected the majority of flows from all large streams in the Central Valley. Building additional storage there would yield only limited incremental water supply at exorbitant costs.

Significant investments in new water storage, totaling more than 6 million acre-feet, have occurred in the last 15 years. Two large off-stream reservoirs, Diamond Valley and Los Vaqueros, recently have been built, providing an additional 900,000 acre-feet in storage capacity. The customers who benefit from the two reservoirs paid the full tab for construction.

Water agencies more often find groundwater development to be preferable to new surface storage. Infrastructure can be installed at less cost so previously depleted aquifers can be replenished in wet years to store supplies for use in dry years. While most of the more than 5 million acre-feet of new groundwater storage has been developed in the Central Valley, contractual arrangements and an extensive conveyance system allow for providing additional supply to communities in both Northern and Southern California.

Progressive and fiscally conservative water supply agencies continue to pursue alternatives that include water conservation, recycling and purchasing supplies on the open market. These approaches not only have worked well, they have saved ratepayers billions of dollars. These alternatives represent everything that California strives to be: innovative, efficient and willing to protect the natural resources that underpin its successful economy.

California leaders should walk away from the attempts to use the Delta's crisis as justification for building the three proposed dams. They should focus now on the most urgent priorities: protecting the Delta's ecosystem and weak levees from potential collapse. Those actions are what will benefit our environment, our economy and future generations of Californians.

About the writer:

• Spreck Rosekrans is a senior analyst for the Land, Water & Wildlife Program at Environmental Defense and a member of the Delta Vision Stakeholder Coordination Group.