What about sea level rise?

One of the arguments for building tunnels under the Delta to move Sacramento River water directly to the export pumps in the South Delta is that tunnels will protect export supplies from sea level rise.  Here are some things to bear in mind on this subject.

First, estimates of possible sea level rise in California vary tremendously.  There is little doubt that sea levels are rising, but the degree and rate of rise are somewhat speculative.  Delta engineers note that levees can be raised incrementally if necessary to keep up with gradually rising water levels.  This will have to be done anyway to protect people and property in the Delta, including infrastructure of statewide importance like highways, railroads, and water and gas pipelines.

Second, sea levels high enough to affect water transfers will likely also affect the proposed water intakes in the northern part of the Delta.  And long before this becomes an issue, large portions of the San Francisco Bay Area will be inundated.  The answer here is not to build expensive tunnels that we may not be able to use anyway (“stranded assets”) but to rethink how we manage water in California, focusing on ways to optimize regional self-sufficiency.