Looming Deadlines for Coastal Resilience

Findings

2020 and 2030: Concerning Numbers of Essential Assets, Buildings, and Services at Risk

Our 2020 results show that roughly 900 critical infrastructure assets nationally are already at risk of disruptive flooding twice per year or more. Public and affordable housing represents the largest category of assets at risk; industrial contamination sites, energy infrastructure, and public safety and health facilities are also highly exposed. In some instances, this potential flooding is being prevented by coastal defenses, such as seawalls, raised buildings, and other flood control measures, that are not well captured in our underlying data. Our current patchwork of coastal defenses and risk mitigation measures, however, is unlikely to completely stave off the more frequent, more extensive inundation to come (Hermans et al. 2023).

With the medium scenario, our data between 2020 and 2030 show a sharp increase in the amount of infrastructure exposed to two or more disruptive flooding events annually, from 904 assets nationally in 2020 to 1,085 assets nationally in 2030, or a 20 percent increase (see Table 2). This near-term increase in exposure is largely the result of past global carbon emissions, with only minor differences seen across the range of sea level rise scenarios through the end of this decade.

Of the critical infrastructure assets at risk in 2030 under the medium scenario, 717 would be inundated approximately monthly, a 17 percent increase from 2020 conditions. The communities with at-risk infrastructure in 2030 are currently home to nearly 2.2 million people—roughly Houston’s population (Census Reporter Profile 2022). Atlantic City, New Jersey, is among the hardest-hit communities in this time frame, with 44 public and affordable housing facilities at risk of flooding twice annually by 2030. Communities in southern Louisiana are also expected to be heavily affected by this time. In the town of Raceland, in Lafourche Parish, 16 public housing buildings, an electrical substation, and a sheriff’s office are all in danger of flooding twice annually by the end of this decade.

Of note, communities designated as disadvantaged contain nearly twice twice as many at-risk assets per capita as nondisadvantaged communities. Throughout this report, we define disadvantaged communities as those census tracts designated so by the Climate and Economic Justice Screening Tool (CEJST) developed by the White House Council on Environmental Quality (CEQ 2022). The tool’s methodology identifies communities as disadvantaged based on the combination of burdens they face in a number of different categories, including health, housing, and climate change. (See #10 of Assumptions, Limitations, and Caveats and the more detailed Methodology document at www.ucsusa.org/resources/looming-deadlines-coastal-resilience.)

Although we use the CEQ’s terminology in our study, we note that this wording—disadvantaged—emphasizes the harms experienced by these communities rather than the systemic nature of injustice or the communities’ strengths and assets (Horgan et al. 2024; Sotolongo 2023; Tuck 2009). In addition, an important limitation of the tool’s methodology is that it does not consider race, which likely means the tool overlooks some communities that have experienced past and ongoing racism and are undoubtedly disadvantaged as a result. Race data are made available, however, through the CEJST, and we included these in our analysis to examine the racial makeup of communities that the tool identifies as disadvantaged.

Roughly one-third (35 percent) of communities in coastal counties are considered disadvantaged, but they are home to 53 percent of the infrastructure at risk by 2030 under the medium scenario. Additionally, communities in which five or more infrastructure assets are at risk are home to a disproportionately higher percentage of Black residents compared to the national average. Nationally, about 12 percent of people in the United States identify as Black or African American, but in communities with high exposure, Black residents make up, on average, 21 percent of the population.

This greater potential to be affected by flooding is poised to exacerbate existing, unaddressed inequities caused by environmental racism and toxic pollution. These inequities become particularly acute regarding increases in the number of critical infrastructure sites that will be inundated twice per year between 2020 and 2030 in disadvantaged and nondisadvantaged communities. During this decade, our results show a 10 percent increase in public and affordable housing exposed to disruptive flooding twice per year in nondisadvantaged communities but a 40 percent increase in disadvantaged communities. These results may reflect a higher concentration of public housing in disadvantaged communities than in nondisadvantaged communities. During the same period and with the same inundation frequency, the numbers of brownfields and K-12 schools exposed to flooding also increase more rapidly in disadvantaged communities than in those that are nondisadvantaged.