Delta levee projects must now prepare for rising sea level

Levee projects in the Sacramento-San Joaquin Delta will have to account for rising sea levels under a new federal policy aimed at shoring up the region’s main line of defense against climate change.

It’s the first comprehensive policy by the U.S. Army Corps of Engineers to require that projects under its jurisdiction be designed with higher sea levels in mind.

Many low-lying areas on the edges of the Delta would be under water given the higher seawater levels predicted by the end of this century. Fragile Delta levees also could be overtopped, especially when high tides and storm surges are added into the mix.

“Regardless of what you think the reason is, sea level is rising worldwide and it will continue to rise in the future,” said Kevin Knuuti, chief of the engineering division at the Army Corps’ Sacramento District and lead author of the new policy. “I think the bigger victory is really increasing awareness. We recognize we have a better job to do with that, and that’s why we have come out with this policy.”

One of the oldest sea level monitors on the West Coast, at the Golden Gate Bridge, has recorded a sea level increase of about 2 centimeters per decade during the 1900s. This rate is expected to continue due to human consumption of fossil fuels, which scientists believe is gradually warming the Earth’s climate.

Failure to consider this increase in new levees and coastal structures