Now Playing

Maps of Sea-Level Rise, Ranked from Kinda Scary to OMFG

How much of the Bay Area could be inundated by 2100? See the slideshow below.


An interactive map by Climate Central breaks down the dollar value of all the coastal property within three feet of the local high-tide line.

(1 of 4)

And here's all the coastal property within six feet of the local high-tide line.

(2 of 4)

Eight feet.

(3 of 4)

Ten feet.

(4 of 4)

On the heels of last month’s terrifying study by former NASA climatologist James Hansen, which predicted that sea levels could rise as much as ten feet in the next 50 years, comes an equally alarming new report by the San Francisco Public Press looking at the large sums of money now being pumped into development on land that could be hit by floodwaters within 100 years. The Bay Area's developers, it appears, are building as fast at they can on land that is in great danger of being subaquatic in the not-too-distant future.

According to the report, the region's builders are on track to invest more than $21 billion in offices and residences on land that could be inundated by century’s end. The Public Press’s roundup of flood-prone developments focuses on major projects planned for areas whose elevation falls within eight feet of current high-tide levels. And it reads like a who’s-who of the Bay Area’s most buzzy projects, from the roughly $1 billion proposed Warriors arena in Mission Bay to Facebook’s recently completed Frank Gehry-designed West Campus, estimated at $185 million.

Unlike the Hansen study, which has not yet been peer reviewed, the Press relies on models that predict occasional flooding as high as eight feet if a severe storm occurs, though they explain that even in the current “most likely” scenario of a three-foot rise, thousands of acres of shoreline would be underwater. SPUR sustainable policy director Laura Tam, who was not involved in the Public Press report, explains via email that three feet is the "generally accepted, based-on-science, planning-level expectation" for the Bay Area for the average high tide in 2100. "Of course, it is just a ballpark,” she writes. The higher estimate of eight feet would come to pass if sea levels rise more—say, 55 inches—and then we're hit with an uncommonly big storm, sending storm floodwaters over and above the high-tide levels. “Eight feet is more equivalent to a 100- or 200-year storm," writes Tam, "or an even larger storm sooner than that (a 500- or 1000-year storm, perhaps). That would be a rare, severe event.” Still, even that more modest—if any flood can really be called modest—estimate of three feet would threaten swaths of Mission Bay and Hunters Point, the sites of two of the city’s most substantial growth spurts.

Why do we keep building on the water when the water’s going to inundate us all? Ever since we began filling in the bay and locking in our dependence on icecap-melting greenhouse gases, development and sea-level rise have been on a collision course. And in sprawly Silicon Valley, where smart urban planning would normally call for concentrating new development near existing transit and services, adding density would send the booming tech class straight into the surf, as this scary map by the nonprofit GreenInfo makes all too clear.

Some of the developments that made the Public Press's list do take precautions—Gehry built Facebook’s new building on stilts for a reason—but others sound willfully myopic, in the report's telling. The Warriors arena’s environmental report downplays the risk of sea-level rise not on the basis of science but “lack of regulatory clarity,” as the Press has it. So when floodwaters encounter red tape, they’ll just get discouraged and turn around?

Debates over waterfront development usually zero in on rooflines, but maybe everyone's focusing on the wrong end of the building. If we don't get the right kind of wall on the waterfront—think expensive seawalls or levees—will there be any beachfront land left for the Art Agnoses of tomorrow to fight over? Come 2100, will we be rooting for the Golden State Warriors water polo team?

With the help of nonprofit news organization Climate Central's holy-crap-inducing map of sea-level rise, we grabbed a few telling screenshots of the land affected by surges of three, six, eight, and ten feet. In each scenario, Climate Central maps the value of the property that falls within each respective elevation—and we wish we didn't have to clarify that those dollar values in the key are per acre, not absolute totals. Play with the whole depressing thing here. Oh, and this map of changing sea levels is pretty bracing, too.

Have feedback? Email us at

Email Lamar Anderson at
Follow us on Twitter @sanfranmag
Follow Lamar Anderson on Twitter @srslynow