It’s no secret San Francisco is due for a major earthquake that will rival the devastating magnitude-7.8 temblor of 1906.
There’s a one in three chance the Hayward fault alone will produce a magnitude-6.7 or larger quake in the next three decades.
The City is preparing for such an event by requiring at an unprecedented level various seismic upgrades and evaluations of residential, commercial and educational buildings. Rebuilding major infrastructure of the Bay Bridge and Doyle Drive to meet seismic safety standards are other major efforts to prepare San Francisco for “the big one.”
But it remains unknown exactly what will happen in a major quake to the four miles of northern waterfront stretching from Fisherman’s Wharf to AT&T Park. That area constitutes the Northern Waterfront Seawall – some of the most valuable land in the world and a gate for thousands of people who enter and leave The City each day.
“In major earthquakes around the world we’ve seen major damage along the waterfronts,” said Steven Reel, a project manager for the Port of San Francisco. “The waterfront [in San Francisco] is built on filled land that’s historically not performed very well.”
That’s why the Port commissioned a $425,000 consultant-led study earlier this year to explore how the Northern Waterfront Seawall – composed of more than 40 different combinations of rock dike, bulkhead wall and bulkhead wharf – would fare in an earthquake.
The study is expected to be complete early next year, though an informational update was presented at a Port Commission meeting Tuesday, less than a week before the 26th anniversary of the Loma Prieta earthquake on Saturday.
“The results of this study will help inform what we can do to improve things but also tie in together with the response to sea level rise and may set the framework for the overall [waterfront] planning,” Reel said.
But what’s unique about the effort is that for the first time the Port is examining the resiliency of the waterfront during an earthquake combined with impending sea level rise and climate change — both factors that are also expected to impact the waterfront in the coming decades.
“The earthquake vulnerabilities and mitigation measures, if there are any that are recommended, will really tie into the response to sea level rise,” Reel said.
San Francisco Bay waters are projected to rise as much as 6 feet by 2100, and as much as $5 billion may be needed within the next two decades to rebuild the wall that has been San Francisco’s waterfront for the past century, the San Francisco Examiner previously reported.
Tackling such needs along with the results of the earthquake vulnerability study will allow the Port to plan better for waterfront needs in the coming years, said Reel.
“Before 2050 there’s a very good chance we’re going to have one or more major earthquakes. That’s going to be something The City hasn’t seen since 1906,” he noted. “If we find that that type of earthquake is going to cause significant damage to the waterfront and that it is very costly to mitigate that kind of damage, it’s going to tie in with [our] response to sea level rise.”