California water officials are proposing a dramatic redesign of two massive water diversion tunnels planned for the Sacramento-San Joaquin Delta, a concession to Delta residents who have complained the project would upend their lives.
In plans to be made public today, the California Department of Water Resources proposes moving the 40-foot-diameter tunnels farther east, away from the towns of Courtland and Walnut Grove.
It also is shrinking a proposed water storage reservoir, called an intermediate forebay. The initial design called for a footprint of 750 acres and located the reservoir next to Stone Lakes National Wildlife Refuge. Now it would be 40 acres and located 10 miles farther south, near Twin Cities Road.
Another significant change involves the handling of so-called "tunnel muck," the mix of dirt and drilling chemicals removed by the tunneling machines. The new design calls for fewer muck disposal areas on private land. Instead, DWR would use state-owned land near Interstate 5 in Sacramento County bought long ago for the Peripheral Canal, an earlier iteration of the massive Delta replumbing effort that voters defeated in 1982.
"I hope this indicates that we are serious about doing our best to reduce impacts to Delta residents," said DWR Director Mark Cowin.
The new design, however, comes with new concerns. The big one is that the tunnels now pass under Staten Island, owned by The Nature Conservancy and protected by conservation easements to preserve wildlife habitat.
Three large vertical shafts are proposed on Staten Island to "launch" and service the tunneling machines. Each includes a surface work area as big as 90 acres.
Two large muck disposal areas are also proposed on the island, the largest on its southeast corner, an important refuge for greater sandhill cranes, a threatened species under state law.
"It's very, very troubling and may even be a disaster for sandhill cranes," said Mike Savino, president of Save Our Sandhill Cranes, a Sacramento group that advocates for the birds. "I hope and pray there's an alternative, or that the law doesn't allow it."
The tunnels are part of the Bay Delta Conservation Plan, an effort by the state to resolve decades of conflict over the Delta's freshwater supply. That water serves 25 million Californians and 3 million acres of farmland, and also supports the largest estuary on the west coast of the Americas.
The new Sacramento River intakes and tunnels are intended to kill fewer fish than existing diversion pumps near Tracy, and protect the freshwater supply flowing south from floods and earthquakes.
The plan is estimated to cost $25 billion, including 100,000 acres of habitat restoration. The tunnels and intakes would account for $15 billion of that total, to be paid for by water ratepayers who benefit from the project. This includes urban areas in Silicon Valley, Los Angeles and San Diego, and farmers in the San Joaquin Valley.
The proposed changes aren't expected to alter the project's timetable, state water officials said, though they held out the possibility that its cost might be reduced.
A formal draft of the plan is to be released by Oct. 1. The goal is to obtain approval as a habitat conservation plan under state and federal endangered species acts.
Residents still wary
Other design changes to be announced today include:
Highway 160 detours around the north and middle intakes will follow a broader path along an old railroad embankment, impacting fewer homes and local roads.
Buildings at the three intakes will be shrunk from 60 feet high to 30 feet, about as high as a two-story house.
The new tunnel route and muck disposal plan means the project will eliminate fewer homes: 19 instead of 37.
Sacramento County farmer Daniel Wilson stood to lose both his home and his agricultural packing shed to the previous design. Under the new plan, both are preserved.
"I'm very pleased the tunnel is no longer burying my house in muck," Wilson said. "The new route is better from the standpoint that it doesn't destroy my livelihood."
But like many Delta residents, Wilson still vows to oppose the project because of other fundamental changes it poses, including altered Sacramento River flows and water quality, and disruption of roads, traffic and scenery.
"It's better conceptually, but it's still going to have a massive impact on the Delta," Wilson said. "This change is probably a product of them finally starting to pay at least some lip service to Delta interests."
The revisions make Staten Island a new focus of concern.
The 9,100-acre island lies in San Joaquin County, between two forks of the Mokelumne River. California taxpayers spent $32 million from two bond measures in 2001 to preserve the island as wildlife habitat.
The island is owned and farmed by The Nature Conservancy, a nonprofit group. A permanent conservation easement covers the entire island, limiting activities to those that "preserve agricultural land, protect wildlife habitat, and protect this floodplain area from inappropriate and incompatible development."
DWR holds title to the conservation easement – and monitors the conservancy's compliance with it – because it disbursed some of the bond funds to buy the island in 2001.
Legal issues loom
It is an open legal question whether the easement will prevent tunnel construction.
Cowin said he could not comment on the legal issues, which have not yet been analyzed. But he said DWR believes the tunnels will help the island.
"We think using the material that we dig out of the tunnels to further enhance the terrain and habitat values would be an ultimate plus for Staten Island," Cowin said. "We think the long-term benefits could definitely outweigh the short-term impacts."
The Nature Conservancy is in an unusual position on the issue. In 2009, it became the only environmental group to declare its support for the Bay Delta Conservation Plan. That support was conditioned upon having a new and independent government agency in charge of operating any new water conveyance, which still is not part of the plan.
Dawit Zaweke, Central Valley regional director for the conservancy, said his group has not taken a position on the new tunnel alignment. He said it needs to gather more information about potential environmental impacts and what kinds of restoration might occur.
"I don't think anything on this scale has ever been done in California, so it's really hard to have an opinion just off the cuff," Zaweke said.
Sandhill cranes are thought to be the oldest known bird species, with a lineage traced back 10 million years through fossil records. The subspecies that winters in the Central Valley is not unique, but is part of a migratory group that does not mix with cranes east of the Sierra Nevada.
Staten Island is considered essential to cranes because it is relatively isolated. The birds are known to be sensitive to noise, lights and other human activity. They are also "philopatric," or loyal to particular places.
Individual cranes will return to the same place year after year, said Mike Eaton, the former director of Delta projects at The Nature Conservancy who negotiated the Staten Island easement more than a decade ago.
"What I learned from The Nature Conservancy about conservation easements is that they are sacrosanct, not to be altered or retreated from for any reason," said Eaton, who now lives in Galt and is active with Save Our Sandhill Cranes. "That the organization is even opening the door to consideration of this level of impact on Staten Island is alarming."
Contact The Bee's Matt Weiser at (916) 321-1264. Follow him on Twitter @matt_weiser.