Belvedere's century-old seawall is crumbling, adding to Bay Area concerns with rising sea levels

In Belvedere, a seawall has kept the water at bay for more than a century.

But the problem is after all that pounding, the seawall along Beach Road is crumbling. The broken guard rail is the most obvious sign, though the real trouble is underneath.

"It is being undermined by wave action over many, many years. It is becoming more of an emergency where we could get to a tipping point where [the seawall] could eventually fall over into the water," said Belvedere city manager Craig Middleton.

If the city lets it go, the fear is flooding during the rainy season, so the plans are to fix it for about half a million dollars.

"The whole place is susceptible to sea rise," he said. 

That seawall may be the most pressing problem. But modifying the one about a mile away on San Rafael Avenue will be a much bigger and a much more expensive challenge.

The San Rafael Avenue seawall is not in danger of collapsing. However, city leaders say they will eventually have to raise it and the Beach road wall another two feet to protect against sea-level rise. That could cost many millions of dollars.

Earlier this week a United Nations report on climate change predicts dire consequences from sea rise. 

Belvedere is far from alone in having to address its seawalls. San Francisco is asking voters to pass an almost half a billion-dollar bond measure next month to strengthen the Embarcadero sea wall.

Racing against rising sea levels is a Bay Area-wide problem.

"For people like me in management positions in the Bay Area, we are talking to each other and getting educated quickly on what we can do," said Middleton.