The History
At the heart of this decades-long conflict is a vision for the state’s water future focused on communities and healthy ecosystems, versus an expensive tunnel project driven by state officials and powerful water agencies.
A History of the Delta Tunnel Project
Northern California’s precipitation is critical to sustaining the region’s watersheds, fisheries, and communities. But for decades, much of that water has been redirected to the drier southern part of the state to support agriculture and urban growth—an effort made possible by large-scale federal and state water projects.
In the 1960s, Governor Pat Brown championed two major initiatives to transfer water from the north to Southern California. His son, Governor Jerry Brown, attempted a similar project in the 1980s—the Peripheral Canal—which was ultimately rejected by voters in 1982. The idea resurfaced in 2009 under Governor Arnold Schwarzenegger, and again under Jerry Brown when he returned to office in 2011. Over time, the proposal evolved from an above-ground canal to an underground dual-tunnel system known as the "twin tunnels." In 2018, years of advocacy from Delta residents and environmental groups helped put a stop to the twin tunnels.
But the project didn’t end there. When Governor Gavin Newsom took office in 2019, he introduced a scaled-down version: a single tunnel, now known as the Delta Conveyance Project.
From BDCP to WaterFix and EcoRestore
Originally called the Bay Delta Conservation Plan (BDCP), the proposal launched in 2009 aimed to both construct the tunnels and restore 100,000 acres of habitat over 50 years. However, the U.S. Fish and Wildlife Service declined to issue permits, citing insufficient evidence that the habitat restoration would benefit endangered species like salmon, sturgeon, and delta smelt.
In response, the Brown administration split the project in two: the WaterFix tunnel proposal and the EcoRestore habitat plan. EcoRestore reduced the scale of restoration to 30,000 acres over five years, at a cost of $300 million, funded through state bonds and other sources. WaterFix focused solely on the water infrastructure component.
Today’s Plan: The Delta Conveyance Project
Today’s version, the Delta Conveyance Project, is estimated to cost $20 billion. The state claims it remains cost-effective, but it still faces serious hurdles: multiple state and federal permits are pending, and legal challenges from environmental and community groups—like Delta Legacy Communities—continue to mount.
If approved, construction could begin by 2029 and take more than a decade. The project’s massive intakes near the town of Hood would span thousands of feet along the riverbank and replace farmland with fuel stations, parking lots, access roads, and industrial facilities such as grout-mixing stations and sludge-drying fields.
Controversy and Local Concerns
Proponents argue the tunnel will modernize the state’s water infrastructure and protect the environment through regulated pumping and existing water quality safeguards. But many Delta residents remain skeptical.
Harvey Correia, a local farmer in the Delta, already battles saltwater intrusion from the San Francisco Bay. He and others fear the tunnel will make things worse, accelerating environmental degradation and threatening the region’s farming economy.
From the failed Peripheral Canal of 1965 to today’s single-tunnel vision, the state’s efforts to divert Delta water have taken many forms. What remains unchanged is the fierce debate over how—and whether—to reengineer one of California’s most vital and vulnerable ecosystems.
