Flooded roadway.

If a new study led by the University of Bristol is to be believed, 41 million Americans are at risk from flooding rivers, according to phys.org. That's more than three times than the current estimate of 13 million people.

The Bristol study is based on a new high-resolution model that maps flood risk across the entire continental U.S., whereas the existing regulatory flood maps produced by the Federal Emergency Management Agency (FEMA) cover about 60% of the continental U.S.

The increase in numbers of those at risk is a result of the expanded coverage of the map combined with its ability to estimate flooding on small streams — something that wasn't adequately captured in previous flood-risk models, according to the study's researchers.

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Shawn Moynihan

Shawn Moynihan is Editor-in-Chief of National Underwriter Property & Casualty. A St. John’s University alum, Moynihan has earned 11 Jesse H. Neal Awards, the Pulitzers of the business press; seven Azbee Awards, from the American Society of Business Press Editors; two Folio Awards; and a SABEW award, from the Society of American Business Editors & Writers. Prior to joining ALM, he served as Managing Editor/Online Editor of journalism institution Editor & Publisher, the trade bible of the newspaper industry. Moynihan also has held editorial positions with AOL, Metro New York, and Newhouse Newspapers. He can be reached at [email protected].