Coastal flooding is getting more common, even on sunny days

Coastal flooding from high tides is getting more common in most parts of the United States, as climate change causes sea levels to rise.

Millions of people are affected by so-called sunny day flooding each year, according to a new report by the National Oceanic and Atmospheric Administration (NOAA). On average, the U.S. now experiences five extra days of high-tide flooding each year compared to the year 2000.

“Over the past year we’ve seen record coastal flooding,” says Nicole LeBoeuf, the director of the NOAA National Ocean Service.

In the last year, St. Petersburg, Fla., Atlantic City, N.J., Charleston, S.C. and more than 30 other places tied or broke their records for the number of high-tide flood days. Galveston, Texas, which consistently sees some of the most severe and frequent high-tide flooding of any city in the U.S., experienced 23 days of high-tide flooding last year.

The costs of high-tide flooding are enormous. Even a few inches of water can make neighborhoods inaccessible to some residents, including those who use wheelchairs or rely on strollers to transport young children. And standing water can also snarl commutes, block emergency vehicles and cause secondary flooding if sewers back up into buildings or overflow into natural bodies of water.