Coastal communities saw record-setting high-tide flooding in past year: NOAA

Coastal communities in the U.S. saw record-setting high-tide flooding in the past year and this trend will likely continue unless flood defenses are improved upon, the National Oceanic and Atmospheric Administration (NOAA) said Wednesday.

The agency looked at high-tide flooding patterns from May 2020 to April 2021 based off its 97 tide gauges found along the U.S. coast. High-tide flooding, which occurs when tides reach 1.75 to 2 feet above the daily average high tide and start spilling onto streets or bubbling up from storm drains, has become increasingly common as sea levels rise, it found.

The report found that coastal communities experience two times as many high-tide flooding days than they did 20 years ago. At last 80 percent of the locations where NOAA collected data experienced an acceleration in the number of these flooding days.

“As sea level rise continues, damaging floods that decades ago happened only during a storm now happen more regularly, such as during a full-moon tide or with a change in prevailing winds or currents,” the agency said in a press release.

Areas of particular concern for NOAA include Florida, Georgia, Mississippi, South Carolina and Texas. NOAA noted some coastal cities saw 10 times the amount of flooding days they would normally be expected to see 20 years ago.

“High-tide flooding disrupts people’s lives when they can’t get to and from work or have to repeatedly deal with a flooded basement,” Nicole LeBoeuf, the director of NOAA’s National Ocean Service, said. “NOAA is committed to working with coastal communities to provide the information and tools they need to tackle the problem of high-tide flooding, both now and in the coming years as sea levels continue to rise.”

Projections indicate that by 2030, these towns will see an average of seven to 15 high-tide flooding days. That number is projected to rise to 25 to 75 days by 2050.