Opinion: Delta mega-tunnel is not the answer to state’s water challenges

Real water resilience requires managing our existing water resources more responsibly and thoughtfully.

Climate change is rapidly affecting California’s environment. From drought to catastrophic floods and landslides occurring from unprecedented atmospheric rivers, to sea-level rise and reduced snowpack, there are many water challenges facing the state.

The solution to these problems is not a $16 billion mega-tunnel paid for by ratepayers that won’t be completed until 2040 at the earliest. We need solutions now — solutions that won’t cause further damage to already overburdened ecosystems and communities.

The Department of Water Resources’ claim that the Delta tunnel could have moved an additional 228,000 acre-feet of water into San Luis Reservoir during the month of January if it had been operational this year is misleading. The Delta  tunnel would not have added any additional supply or contributed to long-term water resilience because there isn’t enough storage space to hold the “additional” water south of the Delta for the next dry year.

Given the hydrological forecasting under climate change, the tunnel would also not be able to move additional water during the extreme dry periods, when Californians need it most, without causing detrimental impacts to wildlife, ecosystems, and communities in the Sacramento-San Joaquin River Delta.

Contrary to the proponents’ arguments, the current system was able to capture and move water this year. The state and federal water projects both provided participating agencies with 100% of their assigned allocations and additional water was made available to those who could use it. In Santa Clara County, all of our aquifers are now full, providing a buffer for future drought years.

The proponents of the tunnel state that it will benefit Northern California, which is untrue. It may provide some benefits for south-of-Delta water users such as Santa Clara County, but any benefits are unlikely to measure up to the cost. Despite years of work on this project, no comprehensive cost/benefit study has been completed.

The costs of the project include environmental costs. The freshwater flowing into the Delta has been overdrawn for decades, resulting in loss of habitat, fish and wildlife. Lack of freshwater flows and high temperatures in the Sacramento River have caused historic die-offs of winter-run Chinook salmon, forcing the closure of the salmon fishery this year, creating devastating economic impacts to the fishing industry, and cultural impacts to tribal nations across the state.

Because of climate change, the Delta is also suffering from increased algal blooms that put Delta communities at risk of air and water pollution. Delta communities and farms are also at risk of salinity intrusion from the San Francisco Bay as sea levels rise, threatening their water supplies. By diverting freshwater away from the Delta ecosystem, the tunnel will make the problem of salinity intrusion even worse.

Real water resilience requires managing our existing water resources more responsibly and thoughtfully. Additional surface storage projects and the Delta tunnel project would be irresponsible and expensive; it would not provide new water for California when we need it most. The state can meet its water demands now and in the future by focusing its investments on truly climate-resilient infrastructure: recycling, conservation, water efficiency, storm-water capture and better ground water management for urban and agricultural users.

Molly Culton is a senior conservation organizer for the Sierra Club California. Katja Irvin is chair of the Sierra Club Loma Prieta Chapter Water Committee.