Army Corps weighing options for protecting vital Bay area infrastructure from sea level rise

By Nick SimeoneOctober 10, 2015

San Francisco sea level rise
Global climate change, which experts warn is causing oceans to warm and triggering extreme weather, could push California sea levels up by as much as three feet over the next 50 years, according to NOAA estimates, leading to an increased risk of coas... (Photo Credit: U.S. Army) VIEW ORIGINAL

Predicted rises in sea levels triggered by climate change threaten millions of people and could inflict billions of dollars in property losses and economic damage, particularly in the Bay Area where the U.S. Army Corps of Engineers is considering options for protecting densely populated areas of the coastline including critical infrastructure such as the region's major airport and much of Silicon valley.

Global climate change, which experts warn is causing oceans to warm and triggering extreme weather, could push California sea levels up by as much as three feet over the next 50 years, according to NOAA estimates, leading to an increased risk of coastal flooding. The California Climate Change Center estimates that sea levels have already risen eight inches along the coast over the past century.

So concerned is San Francisco International Airport, a major port virtually surrounded by the Bay, that airport officials have asked the Corps to help it produce a plan to reduce flood risk above and beyond current measures in place which include earth berms and concrete dikes.

One idea being mentioned is increasing the elevation of the entire flood risk reduction system to reduce the chances that key airport facilities, including runways handling hundreds of flights per day will be submerged in the event of tidal flooding. A preliminary report produced by the Corps in July concludes the airport is at significant risk of flood-related damage which it says "could lead to transportation delays throughout the country", with "flood damages predicted for the 50 year period likely to be substantial."

"There is a bit of urgency at SFO because proposed capital improvements may not be permissible until tidal flooding risks are better addressed and account for sea level rise," said Tom Kendall, the chief of planning for the Corps' San Francisco district.

The airport is not the only site in the Bay Area where the Corps is focused on climate preparedness and resilience. In September, district leaders proposed a nearly $175 million plan to help protect the heart of Silicon Valley from catastrophic flooding, "One of the nation's most vital economic areas is at risk," said Lt. Col. John Morrow, commander of the San Francisco District as he presented the results of the South San Francisco Bay Shoreline Interim Feasibility Study to Corps leadership in Washington. In making the case for a federal interest in the project, Morrow said the magnitude of the threat is compounded by the important role the region plays in the world economy. "We need to act now," Morrow said. The threat "has put one of the nation's most vital economic areas at risk."

In addition to these projects, the Corps' San Francisco District is active in a range of flood risk reduction and habitat restorations projects throughout the Bay Area, a region that includes areas which lie at or below sea level and are at risk of flooding not only because of rising sea levels but also by a threatened El Nino weather pattern predicted to impact California later this year. Forecasters warn the pattern is likely to bring heavy rain and elevated water levels to the Bay and with it the threat of devastating flooding to areas along the shoreline, areas that have experienced billions of dollars in damage during previous El Nino events.