(TLP:CLEAR) Research Report Examines the Growing Risk of Coastal Flooding

Summary: A recent study from the research organization Climate Central found that the likelihood of coastal flooding is increasing due to the changing climate. As flooding events become more frequent, critical infrastructure owners and operators should ensure their facilities are resilient to this growing hazard.

Analyst Note: The report, “Coastal Flood Risk Across the U.S.,” states that coastal floods in the U.S. occur three times more often than they did 30 years ago — and both the frequency and intensity of coastal flooding are projected to increase due to the changing climate. By 2050, floods are projected to occur ten times more often than they do today. This is because rising sea levels push tides and storm surges higher and further inland, driving this accelerated flood risk.

Additionally, previous research from Climate Central found that the changing climate is affecting three key drivers of inland flooding:

1. Intense rainfall is increasing. Warmer air holds more moisture; specifically, 4% more water vapor for every 1°F of warming. This relationship supercharges the water cycle, bringing heavier rainfall extremes. 
2. Droughts are lengthening, and soil is drier. With more heat comes more evaporation and transpiration of water from soils, leading to drought in some areas such as the southwestern U.S.
3. Mountain snowpack is decreasing and melting earlier. 

Highlighting the threat to critical infrastructure, a AP report from 2023 determined that about one-third of wastewater facilities in the U.S. would be at risk of flooding if an extreme precipitation event hit their area today. Many drinking water utilities will likely face similar vulnerabilities as flood risks continue to grow.

Original Source: https://www.climatecentral.org/report/coastal-flood-risk-across-US  

Additional Reading:

• Climate Change and Inland Flooding
• Over Half of U.S. Population Twice as Likely to Experience 1-in-100 Year Flood, New Research Finds

Mitigation Recommendations:

• EPA – Flood Resilience: A Basic Guide for Water and Wastewater Utilities
• EPA – Flood Resilience Checklist
• FEMA – Floods

Related WaterISAC PIRs: 16 & 17