The impending threat of sea level rise driven by global heating is rapidly becoming a reality for millions of Americans, as hundreds of homes, schools, and government buildings face frequent and repeated flooding by 2050. According to a new study by the Union of Concerned Scientists (UCS), almost 1,100 critical infrastructure assets that sustain coastal communities will be at risk of monthly flooding by 2050, with 934 of them facing the risk every other week. This could make some coastal neighborhoods unlivable within two to three decades.
The impact of coastal flooding will not be equal, as more than half the critical assets facing frequent flooding by 2050 are located in communities already disadvantaged by historic and current structural racism, discrimination, and pollution. These disadvantaged communities have higher proportions of Black, Latino, and Native American residents, and public and affordable housing represents the single most at-risk infrastructure in these communities. The routine flooding of critical infrastructure could lead to some of the most vulnerable and underserved children being forced to travel further for school and medical appointments, as well as the contamination of local water supplies by the flooding of polluted soil.
The analysis by the UCS researchers identified critical infrastructure along the entire contiguous US, as well as Guam, Puerto Rico, and the US Virgin Islands, which face risk of routine flooding. The study found that California, Florida, Louisiana, Maryland, Massachusetts, and New Jersey have the most critical infrastructure that needs to be made more flood resilient – or relocated to safer ground. Without urgent action to reinforce critical infrastructure, the number of schools, apartment blocks, energy facilities, and government buildings at risk of disruptive flooding is expected to rise by at least sevenfold by 2100.
Rising Seas Threaten Coastal U.S.The report, Looming Deadlines for Coastal Resilience, comes at a critical juncture for the climate emergency amid spiraling fossil fuel production and deadly heat, floods, and drought striking communities across the world with increased frequency and intensity. The world’s oceans are rising, and every year seawater reaches farther inland, posing an ever-increasing threat to homes, businesses, and critical infrastructure. By 2030, the number of critical buildings and facilities at risk of routine and repeat flooding along US coastlines is expected to grow by 20% compared to 2020 conditions.
In Charleston, South Carolina, more than 20 high-tide floods were recorded in 2023, sending seawater into the streets and submerging low-lying areas. By 2050, at least 23 essential pieces of infrastructure in Charleston are expected to flood at least twice annually, assuming a medium sea level rise scenario. This includes 17 public housing buildings, which would exacerbate the state’s affordable housing crisis.
The full impact of coastal flooding is likely to be significantly worse, as drinking water facilities, bus and metro stations, and retirement and care facilities for older adults were not included in the UCS study. The analysis looks at flooding driven solely by sea level rise and tidal heights, but does not include other climate-related drivers such as storm surge and heavy rainfall, which can increase the risk of disruptive flooding.