Delaware Floodplain Management State Minimum Standards

Under 7 Del.C. Chapter 41, the General Assembly authorized DNREC to develop guidance and minimum statewide standards for floodplain management and drainage. Every Delaware county and most municipalities participate in the National Flood Insurance Program (NFIP) and must adopt floodplain ordinances meeting 44 CFR Part 60 requirements plus DNREC model standards. Substantial Improvement is defined as reconstruction or improvement equal to or exceeding 50% of pre-construction market value, triggering full compliance with current flood elevation requirements. New residential structures in Special Flood Hazard Areas must elevate the lowest floor to or above the Base Flood Elevation; many Delaware coastal communities additionally require freeboard above BFE.

Building below required elevation, failing to obtain floodplain development permits, or lying on elevation certificates can void NFIP coverage, trigger community NFIP suspension, and result in civil penalties and required structural retrofits.