'Full-blown' salt ponds restoration progresses

By Paul Rogers
KNIGHT RIDDER
Sunday, March 19, 2006

Efforts to restore thousands of acres of former industrial salt ponds ringing San Francisco Bay to tidal marshes for birds and fish are taking a significant step forward.

Working with a floating steam shovel, federal construction crews have spent the past three weeks tearing out sections of earthen levees along three former Cargill salt ponds in the bay between Alviso and Fremont.

When the levees are gone, silt in bay waters is expected to naturally fill in the three-foot-deep ponds, leading to bulrushes and other plants in a few years, followed by fish, ducks and shorebirds -- the first such restoration of ponds that were part of a Cargill sale to the public three years ago. Previous restorations of other ponds involved only installing tidal gates that could be opened to let in bay waters, not actually breaching the levees.

"We're punching holes in the levee. It is a full-blown restoration," said Clyde Morris, manager of the wildlife refuge.

The three ponds, known as "island ponds" because of their remote location, sit on Coyote Slough near the ghost town of Drawbridge. They total 478 acres.

The work is scheduled to be commemorated Monday with a visit by Sen. Dianne Feinstein to the Alviso education center at the Don Edwards San Francisco Bay National Wildlife Refuge.

In 2003, Cargill, based in Newark, sold 16,500 acres of its salt ponds for $100 million to the state Department of Fish and Game and the U.S. Fish and Wildlife Service.

Biologists and environmentalists have hoped for decades to restore the ponds, which cover much of the shoreline from Hayward to Alviso to Redwood City, to marshes where fish such as steelhead, and birds such as sandpipers, pelicans and egrets, could grow in number.

Some of the ponds have been used since the 1800s to evaporate salt for roads, food and medicine. The restoration effort, still in its early stages and expected to take 30 years or more, ranks as the largest wetlands restoration ever on the West Coast, rivaled only by efforts to restore the Florida Everglades and Mississippi River Delta in Louisiana.

The latest work is part of a three-step plan.

In the first phase, crews installed tidal gates on 3,600 acres of former salt ponds between Mountain View and Alviso in July 2004. The gates allowed bay waters to mix with the ponds, diluting their salinity and halting them from making salt.

The second phase involved similar gates that were installed on 2,500 other acres last April from Alviso Slough to Coyote Slough.

The third phase is the current work on three ponds known as A19, A20 and A21. Together, they are about half the size of Golden Gate Park. Because they are at least a mile from the shore, removing the levees will not increase flood risk, said Morris.

After officials opened the other ponds to tidal action, the number of birds wintering in South Bay marshes skyrocketed. Cormorants, pintail ducks, white pelicans and other species are flocking to the new habitat to eat the food that has now spread to the ponds.

The latest work will go a step further and allow silt in the water to actually fill the three ponds.

"It is a sign of progress," said David Lewis, executive director of Save the Bay, an environmental group in Oakland. "The earlier phases created benefits for fish and wildlife," he added. "There are fish in those ponds now. They aren't stagnant isolated ponds. And that has brought birds back."

Meanwhile, state and federal agencies have held dozens of public meetings. They have come up with three alternatives for restoring all 16,500 acres, each with varying amounts of tidal marsh. A draft environmental impact statement is due out by the end of this year, with wider construction work set to begin in 2008, depending on funding.

Since 1850, San Francisco Bay has shrunk by one-third because of diking, dredging and filling for development. Although those changes ended with tough environmental laws by the 1970s, the bay had lost 80 percent of its tidal wetlands -- the key areas that serve as nurseries for young fish, filters to clean bay waters and shelter for birds, ducks and other wildlife.

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