Floodplain Management Requirements

67. What is the role of the community in floodplain management?
When the community chooses to join the NFIP, it must adopt and enforce minimum floodplain management standards for participation. FEMA works closely with State and local officials to identify flood hazard areas and flood risks. The floodplain management requirements within the SFHA are designed to prevent new development from increasing the flood threat and to protect new and existing buildings from anticipated flood events.

When a community chooses to join the NFIP, it must require permits for all development in the SFHA and ensure that construction materials and methods used will minimize future flood damage. Permit files must contain documentation to substantiate how buildings were actually constructed. In return, the Federal Government makes flood insurance available for almost every building and its contents within the community.

Communities must ensure that their adopted floodplain management ordinance and enforcement procedures meet program requirements. Local regulations must be updated when additional data are provided by FEMA or when Federal or State standards are revised.

68. Do State governments assist in implementing the NFIP?
At the request of the Administrator of FIMA, each Governor has designated an agency of State or territorial government to coordinate that State's or territory's NFIP activities. These agencies often assist communities in developing and adopting necessary floodplain management measures.

Some States require more stringent measures than those of the NFIP. For contact information, see the list of State Coordinating Agencies in the back of this booklet.

69. Do Federal requirements take precedence over State requirements?
The regulatory requirements set forth by FEMA are the minimum measures acceptable for NFIP participation. More stringent requirements adopted by the local community or State take precedence over the minimum regulatory requirements established for flood insurance availability.

70. What is meant by "floodplain management measures"?
"Floodplain management measures" refers to an overall community program of corrective and preventive measures for reducing future flood damage. These measures take a variety of forms and generally include zoning, subdivision, or building requirements, and special-purpose floodplain ordinances.

71. Do the floodplain management measures required by the NFIP affect existing buildings?
The minimum Federal requirements affect existing buildings only when an existing building is substantially damaged or improved. There may also be situations where a building has been constructed in accordance with a local floodplain management ordinance, and the owner subsequently alters it in violation of the local building code, without a permit. Such unapproved modifications to an existing building may not meet the minimum Federal requirements.

72. What constitutes "substantial improvement" or "substantial damage"?
"Substantial improvement" means any rehabilitation, addition, or other improvement of a building when the cost of the improvement equals or exceeds 50 percent of the market value of the building before start of construction of the improvement. The term includes buildings that have incurred "substantial damage." "Substantial damage" means damage of any origin sustained by a building when the cost of restoring the building to its pre-damaged condition would equal or exceed 50 percent of the market value of the building before the damage occurred. Substantial damage is determined regardless of the actual repair work performed.

Substantial improvement or damage does not, however, include any project for improvement of a building to correct existing violations of State or local health, sanitary, or safety code specifications identified by local code enforcement officials as the minimum specifications necessary to assure safe living conditions. Also excluded from the substantial improvement requirement are alterations to historic buildings as defined by the NFIP.

73. Do the floodplain management requirements apply to construction taking place outside the SFHAs within the community?
The local floodplain management regulations required by the NFIP apply only in SFHAs. However, communities may regulate development in areas of moderate flood hazard.

74. Can modifications be made to the basic floodplain management requirements?
In developing their floodplain management ordinances, participating communities must meet at least the minimum regulatory standards issued by FEMA. NFIP standards and policies are reviewed periodically and revised whenever appropriate.

75. Does elevating a structure on posts or pilings remove a building from the Special Flood Hazard Area (SFHA)?
Elevating a structure on posts or pilings does not remove a building from the SFHA. If the ground around the supporting posts or pilings is within the floodplain, the building is still at risk. The structure is considered to be within the floodplain, and flood insurance will be required as a condition of receipt of Federal or Federally related financing for the structure. The reason for this, even in cases where the flood velocity is minimal, is that the hydrostatic effects of flooding can lead to the failure of the structure's posts or pilings foundation. The effects of ground saturation can lead to decreased load bearing capacity of the soil supporting the posts or pilings, which can lead to partial or full collapse of the structure. Even small areas of ponding will be subject to the hydrodynamic effects of flooding; no pond or lake is completely free of water movement or wave action. This movement of water can erode the ground around the posts or pilings and may eventually cause collapse of the structure.