In the face of heavy opposition from environmental groups, Governor Gavin Newsom and his administration are pushing forward with a controversial plan to build a 45-mile water tunnel beneath the Sacramento-San Joaquin River Delta. The project, known as the Delta Conveyance Project, aims to modernize the state's aging water system.

State officials released their final environmental analysis of the proposed delta tunnel project on Friday, marking the beginning of the process to seek permits for construction. The tunnel, which would use large pumps to transfer water from the Sacramento River to cities and farmlands in the south, is seen as crucial for addressing the challenges posed by climate change and improving water infrastructure.

Governor Newsom and state water managers argue that the tunnel would help California adapt to worsening cycles of drought caused by climate change and capture more water during wet periods. They also highlight the importance of addressing the risks of infrastructure damage due to earthquakes and flooding.

"Climate change is threatening our access to clean drinking water, diminishing future supplies for millions of Californians," stated Governor Newsom. "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."

Environmental groups have strongly condemned the project, expressing concerns about the potential damage to the delta's fragile ecosystem and the threat it poses to endangered fish species. Opponents argue that the funds allocated for the tunnel could be better utilized for groundwater recharge efforts, water recycling, and stormwater capture.

The debate surrounding the project has been ongoing for decades. Former Governor Jerry Brown initially proposed a two-tunnel project called WaterFix, while Governor Newsom supports a redesigned plan with a single tunnel known as the Delta Conveyance Project.

The proposed project involves the construction of a 36-foot wide concrete tunnel, running approximately 140 to 170 feet underground, and connecting to a new pumping plant that would send water into the California Aqueduct.

California officials assert that the tunnel's two proposed intakes on the Sacramento River would enhance the system's capacity to capture and transport water during periods of heavy rainfall. They argue that the existing infrastructure fails to fully utilize stormwater during wet periods, resulting in missed opportunities.

Proponents of the tunnel project argue that it would improve California's ability to withstand worsening droughts and manage the increasingly unpredictable swings between wet and dry periods.

"We really don't have time to waste in terms of getting all projects moving forward that can secure California in this new hydrologic scenario," emphasized Karla Nemeth, director of the state Department of Water Resources.

Officials estimate that during the intense storms in January, the tunnel could have captured and moved an additional 228,000 acre-feet of water, enough to supply around 2.3 million people for a year.

Advocates for the project underline the need to preserve the backbone of California's water system. They caution that without an update, the current infrastructure remains vulnerable to the effects of climate change and potential damage from a major earthquake, which could disrupt water deliveries to 27 million Californians.

However, California tribes and environmental groups have raised concerns about civil rights violations and mismanagement of water by state officials. An investigation by the Environmental Protection Agency (EPA) has been initiated in response.

Critics, including environmentalists, argue that the state's approach to the project fails to consider the risks posed by accelerating climate change impacts on water supply and sea-level rise in the Sacramento and San Joaquin River watersheds. They claim that the state has neglected to explore alternative options apart from constructing the tunnel.

Barbara Barrigan-Parilla, executive director of the group Restore the Delta, criticized the project, stating that big pipe engineering solutions are no longer suitable for California's climate-changed reality. She emphasized the need to invest in projects that reduce reliance on water exports from the delta, such as underground water storage, stormwater collection, and wastewater recycling.

The contentious issue of the delta water tunnel continues to divide water suppliers and environmental groups in California.