Federal agencies’ dependence on the NOAA Atlas 14 model presents myriad threats, such as undercounting how many homes face severe flood risk and misjudging how often rain will inundate and damage infrastructure. | Noah Berger/AP PhotoThe federal government is relying on an outdated weather model that is putting hundreds of billions of dollars in infrastructure spending at risk, according to a study by climate research firm First Street Foundation.
First Street Foundation developed its own methodology to assess rainfall that found 17.7 million properties face significant flood risk — 12.6 million more than the Federal Emergency Management Agency has identified as falling within the 100-year floodplain, where homeowners are required to purchase flood insurance. Of that total, precipitation was the primary flooding risk facing 8.
“It’s also going to cost a bunch more money because we’re not building it to the right standard,” Eby said. “Literally every state does this.” That “over-smoothing” means some rain events are excluded, and the full-day measurements mean the Atlas 14 model can miss the short-burst downpours that lead to flash floods and are characteristic of a climate-influenced atmosphere, First Street Foundation argued. It also recommended shifting monitoring to shorter timeframes, such as one to six hours.
“Any designs based on outdated weather data and that does not address the unique traits of the region it serves will be a concern, as it can lead to infrastructure or structural projects that are not equipped to withstand current and future climate threats,” he wrote.