Ten U.S. Cities Where Flooding Is Much More Common

A house in Port Deposit, Maryland, is reflected in the floodwater in the home's backyard that surround a bird house, on Sept. 9, 2011. Photographer: Kim Hairston/Baltimore Sun/MCT via Getty Images

Those who dismiss global warming projections might at least note that change has already become a nuisance.

Sea-level rise is making many U.S. cities more susceptible to regular flooding, potentially putting roads, rails, drains and tunnels at risk, according to a new report released today by the National Oceanic and Atmospheric Administration.

The report details the rise in low-grade or “nuisance flooding” in the last 50 years. These are persistent floods, which cause inconvenience rather than injury or death, and may gradually impose costs on local governments to fix or replace infrastructure.

Sea level is higher today than it was in the late 1950s and early 1960s. What that means practically is flooding that once came only during big storms can now come during high tide.

The most significant rise in nuisance flooding is concentrated on the East Coast, with Annapolis, Maryland seeing a 925 percent increase in low-grade flooding over 50 years, to an annual average of 39.3 days. Nearby Baltimore has had a 922 percent increase. The study documents an increased frequency in rising waters, not estimate costs associated with them. With minor floods nine times higher in some places, you can do the math.

The nation’s capital came in eighth on the list of cities with the biggest increases in flood days between the periods 1957-1963 and 2007-2013:

  1. Annapolis, Maryland, 925 percent
  2. Baltimore, Maryland, 922 percent
  3. Atlantic City, New Jersey, 682 percent
  4. Philadelphia, Pennsylvania, 650 percent
  5. Sandy Hook, New Jersey, 626 percent
  6. Port Isabel, Texas, 547 percent
  7. Charleston, South Carolina, 409 percent
  8. Washington, DC, 373 percent
  9. San Francisco, California, 364 percent
  10. Norfolk, Virginia, 325 percent

Enjoy climate change while it's still a nuisance.

More by Eric Roston (@eroston on Twitter):

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