Report: Expect Regular Coastal Floods Within 15 Years

Climate change and rising seas will mean higher flood risks for cities. But when exactly will impactful flooding become a regular occurrence? New analysis by the Union of Concerned Scientists says that time is fast approaching.

1 minute read

October 17, 2014, 11:00 AM PDT

By Philip Rojc @PhilipRojc


Planners working on resilience against flooding take heed. A report, released this month by the Union of Concerned Scientists, says tidal flooding may soon affect urban areas, especially on the Atlantic and Gulf coasts. Forecasts of hurricane and storm risks are plentiful in the wake of Sandy and Katrina, but research into higher tides is harder to come by.

Melanie Fitzpatrick, one of the researchers who compiled the report, remarked, “The shock for us was that tidal flooding could become the new normal in the next 15 years; we didn’t think it would be so soon.”

The team used sea-level data from the recent National Climate Assessment and from Climate Central to determine that “in the absence of flood-deflecting marshes, seawalls or levees, two-thirds of the 52 communities studied can expect a tripling in the frequency of high-tide flooding during the next 15 years.”

The researchers conclude that tidal “nuisance flooding,” though not as dramatic as a major storm, is a real and apparent resilience challenge. They advocate communication between affected cities to coordinate best responses. The article includes an interactive map that displays the report’s flooding predictions for U.S. cities based on a number of parameters.

Wednesday, October 8, 2014 in Climate Central

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I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching. Mary G., Urban Planner

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