From the cockpit of a Cessna airplane flying over the Monterey Bay in early February, you could almost see the future.
The wide sandy beaches disappeared underneath the waves, which were crashing against the dunes and worsening the erosion of our coastline. The Elkhorn Slough swelled and breached some of the brims meant to guide its course. The Union Pacific Railroad tracks were for stretches submerged.
The flight that provided a vantage point for these images took place during one of the highest tides of the year, known as a king tide. It was an aerial tour for the Weekly and KRML radio organized by the nonprofits Surfrider Foundation and LightHawk, two groups that hope to raise awareness about the challenge of sea-level rise.
“King tides can provide a sneak peek into what sea-level rise could look like, and which coastal areas are likely to be most impacted,” the groups explained.
The warming of the planet due to the emission of greenhouse gases is causing the ice caps to melt and the oceans to swell. Within a few decades, ocean water will threaten the most vulnerable stretches of coast in Monterey County and elsewhere. The coastal connection between the Peninsula and Santa Cruz could be severed.
“We need to start acting by that time because we will start to lose vast acres of habitat to saltwater intrusion or agricultural land will flood – and you will start to lose access to Highway 1 because parts of it will be regularly flooded,” says Heather Adamson, the director of planning for the Association of Monterey Bay Area Governments.
Adamson is spearheading a “climate resiliency” study for the Highway 1 corridor near Elkhorn Slough. The work is being done by AMBAG with the help of Caltrans, the Nature Conservancy, the Center for the Blue Economy at the Middlebury Institute of International Studies and others. Bringing together transportation planners, economists and conservationists for this kind of study is somewhat rare, Adamson says, and it’s why Caltrans awarded the effort a $360,000 adaptation planning grant.
The study has come up with several possible responses to the threat of sea-level rise. The highway could be elevated on piles and fill; it could be elevated and widened with an additional lane in each direction; or it could be rerouted inland as part of a managed retreat from the fast-receding coastline.
The estimated cost of these options ranges from $570 million to $750 million, but the spending can be phased in over many years.
“Even with the big price tag, it would cost us more to do nothing,” Adamson says, explaining that the study analyzed a “No Action” scenario. “Doing nothing turns out to be a horrible option,” she adds. “The longer we wait, the worse it will get and the more it is going to cost.”
Until June 11, the public can review the draft of study and submit comments to Adamson by emailing her at firstname.lastname@example.org. The board of AMBAG is expected to vote on the approval of the study in August. After that, Adamson hopes that transportation funding authorities will incorporate ideas from the study into their own plans.