CA Completes Review for Water Tunnel


Last week, California Governor Gavin Newsom’s administration announced that it had completed an environmental review for the Delta Conveyance Project, an underground tunnel meant to capture water during thunderstorms in response to the state’s long-running issue with droughts.

Despite pushback from some environmental groups, Newsom’s administration states that it believes the tunnel could be another way to get water from Northern California, where most of the state’s water is, to Southern California.

This final report is the last step of the state's regulatory process—though reports state that this does not necessarily mean that construction is imminent.

Project Details

According to the Associated Press, the tunnel is expected to be around 45 miles long and 36 feet wide, large enough to carry over 161 million gallons of water per hour.

Last Friday (Dec. 8), the California Department of Water Resources unveiled its final environmental impact report (EIR) for the project, the last step of a complex and lengthy state regulatory process.

However, the report adds that this doesn’t mean that the start of construction on the project is close, as it still must pass a federal environmental review, as well as receive state and federal permits. This process is expected to last until 2026.

The administration states that the tunnel is a much-needed upgrade to the state’s aging infrastructure, potentially protecting the water supply from earthquakes and capturing more water from atmospheric rivers, or rainstorms, that scientists say have occurred more often from climate change.

Officials have yet to state how much the building costs will be, though a previous estimate on a different version of the tunnel was for $16 billion. State officials now plan to release a new cost estimate next year.

Newsom says that climate change is threatening California’s access to clean drinking water, urging that the state’s supply could drop 10% by 2040.

The state recently went three years without significant, sustained rain, causing drops in reservoirs to dangerously low levels and forcing millions of people to ration their supplies. The drought ended suddenly last winter when California was hit by a number of storms that flooded the rivers and filled lake beds that had been dry for years.

State officials stated that if this tunnel had existed during the storms, the state could have captured and stored enough water for 2.3 million people to use for a whole year.

A release from the California Department of Water Resources stated that the Delta Conveyance Project would modernize the state’s water infrastructure to:

  • Capture and move more water during wet seasons to better endure dry seasons;
  • Minimize future losses from climate-driven weather extremes;
  • Protect against earthquakes disrupting water supplies;
  • Continue meeting regulatory water quality and fishery requirements, and add new operating rules for further fishery protections; and
  • Includes a Community Benefits Program to ensure local communities get the means and resources to achieve tangible and lasting benefits.

“Climate change is threatening our access to clean drinking water, diminishing future supplies for millions of Californians—doing nothing is not an option. After the three driest years on record, we didn’t have the infrastructure to fully take advantage of an exceptionally wet year, which will become more and more critical as our weather whiplashes between extremes,” said Newsom.

“This project is essential to updating our water system for millions of Californians. This new approach, redesigned following community and environmental input, is how we can build a California of the future.”

The proposed project reportedly includes a Community Benefits Program, aiming to locate and implement local projects that can provide lasting local benefits.

“Modernized infrastructure in the Delta is a missing link to the state’s most affordable and reliable source of water,” said Karla Nemeth, Director of the California Department of Water Resources.

“Improving water use efficiency and increasing local water supplies is an important compliment to the State Water Project to ensure that a climate proof water supply remains affordable now and into the future.”

The environmental review reportedly included a 142-day public comment period. During that time, DWR reportedly received more than 700 letters and 7,000 individual comments. Outreach began in 2020 and has since then included a multitude of webinars, workshops, briefings, multi-language informational materials, email updates, videos, animations, tabling at local events and a comprehensive Delta survey.

The release states that this final EIR responds to all substantive comments.

“We worked hard to address local concerns and made considerable improvements to minimize terrestrial species effects, wetland impacts, noise, air quality impacts, traffic, power needs, boating and waterway effects, land disturbance, and overall project footprint,” said Carrie Buckman, the project’s Environmental Program Manager.

The release states that this Environmental Impact Report evaluates and discloses to public agency decision makers and the public the potential environmental impacts, and shows feasible mitigation measures to avoid, minimize, or offset potential impacts.

According to officials, the newest report is significant, as it siginals the Newsom administration’s commitment to completing the project in spite of some opposition from communities in the Sacramento and San Joaquin River Delta region.

Environmental groups, Native American tribes and other opponents have voiced concerns that the project could take more water out of the river than is needed, potentially hurting endangered species of fish.

The Sierra Club said in a statement that the tunnel’s construction and operation would “cause mass environmental destruction for Delta communities and ecosystems.” 

Jon Rosenfield, science director for San Francisco Baykeeper, said California already diverts more than half of the water flowing through Central Valley rivers for farms and big cities, which threaten native species of fish.

Fast-Tracking the Project

In May, Governor Newsom proposed plans for new permitting and project review reforms to help streamline and implement infrastructure projects. One project under the plans included the Delta Conveyance Project.

The proposals were expected to help streamline project approval and completion to “maximize California’s share of federal infrastructure dollars and expedite the implementation of projects that meet the state’s ambitious economic, climate, and social goals.”

Other projects that were to be potentially streamlined included:

  • Hundreds of solar, wind, and battery storage projects;
  • Transit and regional rail construction;
  • Clean transportation, including maintenance and bridge projects;
  • Water storage projects funded by Proposition 1;
  • Semiconductor fabrication plants; and
  • Wildlife crossings along the I-15 corridor.

Tagged categories: Environmental Control; Environmental Controls; Environmental Controls; Environmental Protection; Government; Health & Safety; Health and safety; Infrastructure; Infrastructure; NA; non-potable water; North America; Ongoing projects; potable water; Program/Project Management; Safety; Stormwater; Tunnel; Water/Wastewater

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