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California's $20B water tunnel: Benefits outweigh costs, officials say

  • California's $20B water tunnel: Benefits outweigh costs, officials say

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California's ambitious plan to build a giant water tunnel is set to cost over $20 billion, according to Governor Gavin Newsom's administration, reports AP News. The project aims to capture more water during heavy rains and store it to mitigate the effects of prolonged droughts exacerbated by climate change.

This water tunnel initiative, which has been in various stages of planning for decades, represents the latest effort to address California's chronic water shortages. Governor Newsom’s proposal scales down from the two-tunnel plan advanced by his predecessor, Jerry Brown, to a single, giant tunnel. This structure is designed to draw water from the Sacramento River during significant storm events and channel it southward for storage.

The project’s updated cost estimate of $20.1 billion marks a substantial increase from the $16 billion estimate made in 2020. Officials attribute this rise largely to inflation, which has surged in the post-pandemic period. Funding for the project would come from 29 local public water agencies, which derive their revenue from customer payments.

A new analysis by the Berkeley Research Group, funded by the state, suggests the tunnel could yield $38 billion in benefits, primarily through enhanced water security and protection from natural disasters like earthquakes. "The benefits clearly justify the costs," asserted David Sunding, emeritus professor at the University of California, Berkeley, who led the analysis.

However, the project remains mired in controversy. Environmental advocates warn that constructing the tunnel could devastate the fragile ecosystem of the Sacramento-San Joaquin River Delta, the West Coast's largest estuary, home to endangered salmon and other species. The analysis highlights several environmental concerns, including loss of agricultural land, decreased water quality in the Delta, and negative impacts on air quality, transportation, and noise levels.

The project aims to capture more water during heavy rains and store it to mitigate the effects of prolonged droughts exacerbated by climate change

Barbara Barrigan-Parilla, executive director of Restore the Delta, criticized the project, urging the state to pursue sustainable water solutions instead. "Instead of foisting the costs of this boondoggle project onto Californians, the state should invest in sustainable water solutions that promise to restore the Delta ecosystem, not destroy it," she said.

State officials have responded by allocating $200 million for grants to support local projects in areas affected by the tunnel's construction. Despite these efforts, political opposition remains strong, particularly from Central Valley farming communities who view the tunnel as a scheme by Southern California to appropriate their water resources.

"This new analysis acknowledges what we’ve known all along: the Delta Tunnel is meant to benefit Beverly Hills and leave Delta communities out to dry," said U.S. Representative Josh Harder, a Democrat representing Central Valley districts including Stockton, Lodi, and Galt. "I’m sick and tired of politicians in Sacramento ignoring our Valley voices and I will do everything in my power to stop them from stealing our water."

The proposed tunnel, part of the larger State Water Project, is a critical component of California’s water infrastructure. This system, which includes reservoirs, dams, and canals, supplies water to 27 million people and irrigates 750,000 acres of farmland.

Climate change poses a significant threat to this water supply. The recent drought, which spanned three of the driest years on record, severely depleted reservoirs statewide, leading to mandatory water rationing and even the shutdown of some hydroelectric power plants. Projections indicate that by 2070, deliveries from the State Water Project will decline by 22% due to climate change.

The proposed tunnel, which would span 45 miles and measure 36 feet in diameter, is designed to carry more than 161 million gallons of water per hour. State officials argue that this infrastructure will enable California to capture and store water more effectively during "atmospheric rivers" — powerful storm systems that can deliver substantial rainfall over short periods.

According to the recent analysis, the tunnel could increase water deliveries by about 17%, nearly offsetting the expected reductions due to climate change. "There is a very real cost to do nothing. It is vastly more efficient and economical to avoid declining supplies," said Karla Nemeth, director of the California Department of Water Resources. "Water shortages, mandatory restrictions, land fallowing, and job loss all impact our state and local economies."

As the debate over the tunnel continues, the project encapsulates the broader challenges California faces in balancing environmental preservation, water security, and economic stability in an era of climate uncertainty.

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