Storms 20 Times More Likely to Top New York City’s Seawall Than in Mid-1800s

Thanks to sea level rise, New York City’s seawall could be overrun by storm surges every four to five years, says a new paper in Geophysical Research Letters.

The original estimate back in the mid-1800s was that breaches would only occur every 100 to 400 years. 

The paper also found that the more powerful “ten-year storms” — ones with a ten percent chance of hitting in a given year — have increased their flooding potential.  With the added lift from sea level rise, their storm tides can now reach almost six-and-a-half feet, versus 5.6 feet in the mid-1800s.  That’s admittedly a far cry from the record-setting 14.06-foot surge Hurricane Sandy brought to New York City, flooding Battery Park in the process.  But Manhattan’s seawall is only 5.74 feet high.

Storms Are 20 Times More Likely to Top New York City’s Seawall Than in the Mid-1800s