Show All Answers
Some areas also have a Limit of Moderate Wave Action (LiMWA) shown on the FIRM. The LiMWA is the location where the 1% annual chance wave height equals 1.5 feet. FEMA began showing the LiMWA on Flood Insurance Rate Maps to communicate the higher risk that exists in the area because the 1.5-foot breaking wave in the LiMWA zone can potentially cause foundation failure.
Paper copies of the FIRMs for Portsmouth may be viewed in the Department of Planning on the 4th floor of City Hall. For specific flood zone information, please contact Floodplain Management at 757-393-8522.