A community that participates in the National Flood Insurance Program must adopt and enforce a floodplain management ordinance that meets or exceeds the minimum National Flood Insurance Program requirements.

The ordinance must contain construction requirements for new construction or substantial improvement of buildings located in a Special Flood Hazard Area. In addition to other requirements, the ordinance must require that new or substantially improved buildings be elevated so the lowest floor is at or above the base flood elevation or floodproofed to a level equal to or above the base flood elevation (some communities have more restrictive ordinances that require elevation or floodproofing to greater levels).

Work required for compliance with the floodplain ordinance is eligible provided the ordinance meets the eligibility criteria for codes and standards and the substantial improvements are disaster-related repairs. If the cost to repair a facility in accordance with the floodplain ordinance is greater than the cost to replace the facility in accordance with the ordinance, the eligible cost is capped at the replacement cost.