Patricia McBroom, in her blog, The California Spigot, has published an article (August 10) on new thinking about how to safeguard levees in the Sacramento River delta from earthquakes. State planners widely believe that delta levees cannot be built to withstand an earthquake without prohibitive cost. However, McBroom finds an argument otherwise in the most recent draft of the Economic Sustainability Plan for the delta. As she recounts in the article, in the recently released second draft of the plan, earthquake engineer Robert Pyke describes a fat levee with a low probability of breaching and a low cost, compared to other alternatives. In McBroom’s opinion, if Pyke is right, the calculus driving decisions about water infrastructure in California, notably the “need” for a peripheral canal, needs to change.
From the article:
“These levees are the poor stepchild – the one critical feature in California that is still being neglected (for seismic upgrades)” said Pyke, noting that Cal Trans and public utilities in the East Bay and San Francisco have spent billions to upgrade their infrastructure. But levee repair is lagging, even though voters have twice voted for money to fix them.
Many would argue that the delay can be traced to the state’s preoccupation with building a multi-billion dollar “isolated conveyance” (aka, peripheral canal). If the levees can be retrofitted for earthquakes, one good reason for building the canal would be lost, and wealthy interests in the state want the conveyance – actually a tunnel under the delta.
To read the whole article, click here.