Lambertville faces dual threats from floods — localized flash floods caused by heavy rains, and the rising of the Delaware River due to higher water volumes generated upriver. High water velocities, clogging of storm drains, stream bank erosion, and even stream bank failure have all been by-products of flooding. Flooding also can occur when heavy rainfalls collect on the hills and rush into our neighborhoods, as was most recently evidenced during Tropical Storm Irene in 2011.

Lambertville is vulnerable to direct flooding from the rising on the Delaware River and back-flooding local tributaries. Major floods on the Delaware River impacting Lambertville occurred historically in October 1903, March 1936, and August 1955 (record flood), and then most recently in September 2004, April 2005, and June 2006. Heavy rains feeding into the Alexauken, Ely, and Swan creeks can create immediate, localized flash floods.

The City of Lambertville keeps Elevation Certificates on file for some buildings within the floodplain. Contact the Construction Office at (609) 397-0803 or for more information on your local flood hazard.

Floodplain maps and other information regarding local flood hazards and flood protection measures can also be found at the Lambertville Free and Public Library, 6 Lily Street. Ask the librarian for help in determining your location on Google Earth with the National Flood Hazard Layer.