Imagine it’s 2035 and you’re driving into San Francisco on the Golden Gate Bridge. You look out toward the ocean and see ships waiting in a line while a giant metal apparatus closes off the mouth of the Bay, stopping the incoming high tide from flooding the low-lying urban waterfront.
A tidal gate might not be the only solution for dealing with the sea-level increases certain to affect the entire Bay Area, but the nonprofit group San Francisco Planning and Urban Research Association suggests such infrastructure as one in a slew of fixes for the environmental perils likely to result from climate change.
SPUR is releasing a report today titled “Climate change hits home,” which details ways local governments can prepare for the problems likely to occur no matter what steps are taken to lower carbon emissions.
“We need to prepare for some of the effects that are inevitable,” said Will Travis, executive director of the San Francisco Bay Area Conservation and Development Commission, which contributed research that was used in the report. “When we realized our region was riddled with earthquake faults, we didn’t move away, we figured out how to make buildings resistant to earthquakes.”
The report notes that higher temperatures and heat waves could catch local emergency responders off guard when dealing with The City’s lack of air-conditioned residences. Water supplies in reservoirs might be reduced because of a quicker Sierra snowmelt, coupled with less snow and rainstorms that are less frequent, though more intense.
The report identified rising sea levels as the Bay Area’s biggest worry. By 2100, a 55-inch increase in the sea level would increase flood risk throughout the Bay Area — including downtown San Francisco, Silicon Valley and the San Francisco and Oakland airports.
Laura Tam, SPUR’s sustainable development policy director, said the question is not whether sea levels will rise, but rather how much they rise.
“Sea-level rise is a doozy for local governments because there is no precedent for governing it,” she said.
In other words, it’s not a question of if, but rather how much.
Tam said SPUR intends to send the report to local agencies such as the Metropolitan Transportation Commission and private energy providers to consider the future flood risks when planning infrastructure and new development.
Tam said, for example, the Bay Area currently has 22 wastewater treatment plants in the low-lying zones.
Travis said the report’s main message shouldn’t be considered political.
“It’s really an economic imperative,” Travis said. “We can’t turn our back on this problem.”
SPUR’s report suggests several methods of coping with rising Bay waters:
- Tidal barriers: manage tidal flows in and out of San Francisco Bay
- Coastal armoring: protection with levees or seawalls
- Floating development: structures float on the surface or may be floated occasionally during a flood
- Elevated development: raises the height of land or developments
- Floodable development: structures built near retention ponds or water storage devices
- Wetland restoration: absorbs water and sequesters carbon
- Managed retreat: planned abandonment of threatened areas