Water exporters misrepresent the risk of earthquakes to generate support for the peripheral tunnels. Powerful interests control California's water resources and the message about the state's water. Since the devastation of Hurricane Katrina, these powerful interests have stoked fear of flooding and earthquakes to make a case for transforming a unique, beautiful, productive Delta region into a permanent way station for water going somewhere else.
But the peripheral tunnels will not protect California's water supply from an earthquake. Earthquake risk is just as great or greater to the existing canals, dams and local pipes than it is to Delta levees. The existing water project canals, which would continue to be part of the water export system and the San Luis Dam, lie along the Coast Ranges and Central Valley thrust fault and are likely more at risk than the Delta levees. The water distribution system in the southern part of the state is much more vulnerable to earthquakes than Delta levees.
Does it make sense to spend upward of $50 billion to reinforce the first 35 miles of the 400-mile water export system when earthquake threat is equal or higher in other parts of the system? The astronomical cost of the peripheral tunnels threatens investment in a more resilient and disaster-resistant system.
The Hayward Fault, usually cited as the greatest threat to the Delta, is 28 miles from the closest part of the Delta, whereas homes, schools, hospitals and the football stadium of one world-famous university lie right along that fault. The majority of the Delta levees are already fine; others can be upgraded to be robust under any conceivable earthquake, and none of them has ever failed in an earthquake. The U.S. Geological Service recently issued a formal apology for exaggerating earthquake hazards in the Delta.
Fattening the levees is a more effective solution. Rather than making a huge investment in tunnels, let's instead make the levees in the Delta more resilient and prepare California communities to be less reliant on imported water. The cost of upgrading critical Delta levees ranges from about $2 billion to $4 billion. The state claims to be worried about an earthquake in the Delta. But, inexplicably, it is focused on building tunnels to "protect" the water exported rather than on shoring up the Delta's earthquake defenses. The tunnels do not protect critical Delta infrastructure or lives from an earthquake, and even with the tunnels, significant exports would still be conveyed through the Delta channels.
Developing regional self-reliance is the best way to provide a more reliable water supply. This requires investment in water conservation, maximizing wastewater reuse and groundwater recharge, while capturing storm water and rainwater, gray water, and fixing leaky local pipes. Cleaning up aquifers and providing jobs for local water makes economic sense. And, if the governor is concerned about jobs as well as earthquakes, it should be noted that such investments typically create 15 to 20 jobs per million dollars of expenditure, as opposed to the five jobs per million dollars of investment that is touted for the peripheral tunnels.
The best way to restore the Delta and ensure a reliable water supply to other regions is to improve levees to even higher standards; add habitat to those wide, upgraded levees; restore flows in and through the Delta; screen the existing pumps properly; and promote regional self-sufficiency for water development in other parts of the state. Doing so is much more cost-effective than building the peripheral tunnels.
Robert Pyke, a consulting geotechnical engineer from Walnut Creek, was a contributor to the Delta Protection Commission's Economic Sustainability Plan. Barbara Barrigan-Parrilla is executive director of Restore the Delta. They wrote this article for this newspaper.