Local levee upgrades: A massive job

The aim of the missive was to alert the reader that predicted sea level rise could one day become, if not an existential threat to low-lying coastal acreage here, something pretty close to it.

It was a disturbing attention-grabber and that was the point. There’s potential aquatic trouble on the distant horizon, maybe not so distant if some of the more apocalyptic analyses are correct.

A new county agency, the Flood and Sea Level Rise Resiliency District (or OneShoreline), which got its start in 2020, is in the initial stages of addressing what appears to be a long-term problem.

If the data, provided by scientists at the National Oceanic and Atmospheric Administration, along with other experts in the field, is reasonably accurate, miles of county shoreline, both east and west, could be in jeopardy.

OneShoreline officials are using key NOAA climate change findings, many of them generated by computers, to warn that steps must be taken to address this worrisome prediction: Over the next 75 years, ocean and Bay waters will rise at least 1 inch every two years (more than 3 feet).

That follows the previous 125 years when the documented increase was said to be 1 inch every 15 years.

If that stunning projection is close to being accurate, a great deal needs to be done to buttress levees, seawalls, rip-rap and other forms of shore protection.

It won’t come cheaply. San Francisco International Airport authorities are in the early stages of preparing to protect and strengthen SFO’s eight miles of vulnerable shoreline (including creeks/storm drains).

The publicly listed cost estimate for that work is just shy of $600 million. SFO is not part of the OneShoreline purview but it’s interconnected nonetheless.

Property owners in Foster City and the Shoreview area of San Mateo, under pressure from the Federal Emergency Management Agency, are taxing themselves tens of millions of dollars to improve levee protection on those shorelines — and to keep their flood insurance relatively low.

Their peers in Redwood Shores could be next in line for such work for the same FEMA reason. A beach portion of the Coyote Point recreational complex in San Mateo continues to be upgraded. The county recently received state cash to begin a process to raise the levees in Millbrae and Burlingame.

This is just the beginning. There’s a long way to go. According to Dave Pine, chair of the OneShoreline Board of Directors and a member of the county’s Board of Supervisors, projects to counter climate change along the shore could take decades to finish.

And, even then, they might not be enough to ward off the worst aspects of what could be coming. “This will take generations,” he predicted.

To that end, OneShoreline and the county are examining the need for an ultralong-term parcel tax to help to finance the myriad construction efforts under discussion.

That “Under Water?” warning flyer appeared to be the opening salvo to alert voters to the purported dangers ahead. Pine advised that a tax on the county’s 213,000 properties would not be one-size-fits-all.

The aim would be to tax properties on a square-footage basis. He also stated that taxpayers in Shoreview and Foster City and others already shelling out money for levee improvements would not be exempt from a new tax.

“They would benefit from infrastructure protections outside their jurisdictions so they would be subject to a countywide parcel tax,” he offered.

Plus, he said, over time, places like Shoreview and Foster City, will probably require fresh levee improvements. A countywide tax would aid them later, he said.

Pine explained that the county will also rely on federal, state and private sources to pay for the levee/seawall work (for which there is no overall cost estimate).

Financial details are still being analyzed, he said. County officials would have final say on any tax.

OneShoreline’s board still meets via Zoom. Consult its website, https://oneshoreline.org, for updates, agendas and minutes.

Email John Horgan at johnhorganmedia@gmail.com.