"The more we look now, the more creative solutions we can come up with," said Councilwoman Nancy Gardner, who has pushed for research into the issue. "I don't expect us to necessarily be taking action immediately, but I think it's important to have a plan in place."
With higher seas of one foot, most of the Balboa Peninsula, Balboa Island and other areas would be about a foot underwater, according to a 2008 city-commissioned report.
City staff members said they need to examine the 13 miles of concrete walls that line the islands and peninsula. These bulkheads and seawalls protect bayfront homes from water surges, but many of them are already overcome by the extreme high tides like the ones last week.
Estimates vary in how much the water will rise; a study by the Scripps Institution of Oceanography and other researchers shows increases of 16 inches by 2050, and as much as 4.5 feet by 2100. The city cites a range of "1 to 3 feet" by 2100.
Most of the sea walls were built in the 1930s, and they typically last between 50 and 100 years, then-city engineer Lloyd Dalton told the Daily Pilot in 2007. Some are cracked and let in water during less-extreme high tides.
Spot repairs aren't enough to fix the problem, so the city has to develop a comprehensive plan, Gardner said. The main complication is that many of the sea walls are privately owned and maintained, and the city would need the homeowners' cooperation to build higher walls.
At a recent council meeting, Gardner suggested the building code be updated with standards for bulkheads and other protections.
Already, the Municipal Operations Department is adding 1.5 feet of concrete to any city-maintained bulkhead it replaces or refurbishes.
But for a comprehensive reinforcement, there's the question of funding: Should the entire city pay for refurbishing bulkheads, or should most of the cost be borne by homeowners?