An aerial view of the Middle River in the Sacramento-San Joaquin River Delta on Mar. 8, 2019. Photo by Ken James, California Department of Water Resources.


California’s water agency today released a long-awaited environmental report outlining the details and impacts of a controversial proposal to replumb the Sacramento-San Joaquin Delta and pump more water south.

In the report, state officials said the tunnel project could harm endangered and threatened species, including the Delta smelt, winter-run chinook salmon and steelhead trout. To offset the “potentially significant impacts” on the rare fish, the Department of Water Resources says thousands of acres of other wetlands would have to be restored — which critics say is a slow and inefficient way to provide new habitat.

The draft environmental impact report is a major step in planning a tunnel that would fundamentally reshape California’s massive water management system.

The report outlines the proposed path of a 45-mile tunnel that would pipe water from the Sacramento River, bypassing the Delta, and funnel it into Bethany Reservoir, the “first stop” on a state aqueduct that funnels water south.

The goal of the project, which has been planned in various forms since the 1960s, is to shore up water supplies against environmental catastrophes such as earthquakes and the weather whiplash and sea level rise of climate change, according to California Natural Resources Secretary Wade Crowfoot.

Water agencies that can eventually sign on to receive the tunnel project’s water stretch from the Bay Area and Central Coast to the Central Valley and Southern California.

“It is a conundrum to be able to manage the Delta in a way that protects the environment, respects the communities that live there, and provides for the water supplies of a large portion of the state,” Crowfoot said.

The state’s companion explainer for the report, also released today, says changes in flow at and downstream of the tunnel’s intakes “have the potential to decrease migration rates, alter migration routing, reduce availability of rearing habitat, and increase exposure to predation for winter-run Chinook salmon, Central Valley spring-run Chinook salmon, and Central Valley steelhead.”

“It is a conundrum to be able to manage the Delta in a way that protects the environment, respects the communities… and provides for the water supplies of a large portion of the state.”
— California Resources Secretary Wade Crowfoot

Carrie Buckman, environmental program manager for the state’s Delta Conveyance Office, said the department’s analysis found that 4% fewer juvenile winter-run chinook would survive during their peak times in the Delta in below-normal water years.

The summary also notes “potentially significant impacts to delta smelt and longfin smelt” because changes in Delta flow “could affect the species directly or indirectly through changes in factors such as food availability.”

Environmentalists said the project would endanger salmon and other fish that already are in poor shape.

“We know that the status quo is really bad for fish and wildlife, but their own (environmental impact) document shows that the Delta tunnel will make things even worse,” said Doug Obegi, senior attorney at the Natural Resources Defense Council. “You could have a delta tunnel that was environmentally protective, at least in theory, but none of the ones that were proposed or analyzed in here even seem to pass that basic test.”

Buckman said approximately 1,500-3,500 acres of wetlands would be restored to offset the environmental damage.

“The restored habitat would be designed to look and function like tidal wetland habitats currently in the Delta, such as those on Liberty Island,” she said in an email. She added that habitat restoration deadlines will be tied to the project schedule and include provisions requiring restoration ahead of the impacts.

Water experts and environmentalists question, however, whether restoring other wetlands would protect salmon and other fish.

“The state has a bad track record of getting habitat mitigation completed,” said Greg Gartrell, a consultant and retired water manager from the Contra Costa Water District. “They’re very slow, and they’re very meticulous. But they get in their own way.”

A priority of Gov. Gavin Newsom, the effort has also drawn opposition from environmental groups and Delta residents, who worry that drawing freshwater away from the Delta coupled with years of construction will leave the region salty, stagnant and barren.

“I fear that the Delta would eventually just become basically ghost towns,” Kathy Bunton, a Delta resident who owns Delta Kayak Adventures, told CalMatters last month. “It’s just heartbreaking.”

The 3,000 page draft lays out the potential operations of the tunnel routes and their environmental consequences. Alternate routes that were also considered would connect to an existing pumping plant in the south Delta.

“This project is critical to ensuring Californians have access to high-quality, affordable and reliable water supplies amidst the growing impacts of climate change,” Jennifer Pierre, general manager of the State Water Contractors, an association of public water agencies, said in a statement.

The draft “clearly shows that the project has been downsized, refined and redesigned to avoid and reduce local impacts and address environmental concerns,” she said.

The long-awaited tunnel project has been at this point before: Another environmental impact report was finalized in 2016. Yet that project, a pair of tunnels, stumbled because of the high costs and eventually died when Newsom withdrew the administration’s support.

Among other impacts of the tunnel are the removal of 71 structures, including 15 residences; the conversion of more than 2,300 acres of farmland considered to be of “statewide importance”; disruption to cultural and historic sites and resources; and construction noise.

Planning, building tunnel could take until 2040

The price tag hasn’t yet been updated but the cost would be in the billions. In 2020, one of the alternate paths was estimated to cost just under $16 billion. The state plans to issue bonds to fund the final design and construction process. Water agencies receiving the water will be required to pay the state back.

Plans to replumb the Delta have been decades in the making, changing shape over time from a canal to twin tunnels to, eventually, a single tunnel that Newsom promoted when he took office.

If eventually approved, the project would take decades more to complete. Californians will have 90 days to comment on the draft environmental impact report, one of the first steps in a permitting process that could last years. Construction, which is not expected to start before 2028, could take another 12 to 13 years to complete.

Crowfoot said the state is moving as quickly as it can. But he said the state must be cautious because it’s likely it will face lawsuits.

“The governor is committed to getting this project essentially in a place where it’s getting built by the end of this administration,” Crowfoot said. “It’s got any number of potential environmental litigants. We have to do what’s required under the law.”

The State Water Project supplies 27 million people and 750,000 acres of farmland — transporting water through the Delta south with pumps so powerful, they can make rivers run backward.

“This project is critical to ensuring Californians have access to high-quality, affordable and reliable water supplies amidst…climate change.”
— Jennifer Pierre, general manager of the State Water Contractors

Piping water from north of the Delta during wet spells while continuing to pump from the south would allow state water managers to send 540,000 more acre-feet of water south during an average year, or 316,000 in a dry year, compared to existing conditions, according to the documents released today. It’s enough water to supply between 1.1 and 1.9 million households for a year.

Buckman stressed that these numbers are under 2020 conditions, and “do not capture anticipated supply shortages” in the future, when supplies are expected to decline because of climate change and sea level rise.

This year, due to prolonged drought, water providers relying on the State Water Project are receiving 5% of their total 4.1 million acre-foot allocation — less than 220,000 acre-feet.

“With significant water shortages on the horizon, it is mind boggling that the Delta Conveyance Project is the first priority of the Department of Water Resources and the Newsom administration,” Barbara Barrigan-Parrilla, executive director of the advocacy group Restore the Delta.

The analysis also “identified the potential for small increase in salinity in the western Delta,” Buckman said in an email, that “would not exceed water quality objectives.”

Gartrell expects more disputes over the potential risks and benefits of the proposal to play out now that the report’s been released — a continuation of what he has called “the epicenter of the California water wars for almost 60 years.”

“It’s something that a lot of people will dig into and give them things to argue about,” he said. “As if they needed it.”

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