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What Should I Consider if I Choose to Develop in a Floodplain?

Development in the floodplain may result in adverse effects to the floodplain that can lead to the degradation and loss of natural functions and habitat. This degradation and loss can occur through clearing vegetation, placing fill, covering floodplains with impervious surfaces, rerouting stormwater, increasing pollution sources, and channelizing rivers. In particular, these development actions could have direct and indirect detrimental effects on the quantity and quality of floodplain habitats used by fish and other wildlife. If appropriate avoidance, minimization, or mitigation measures are not implemented, the negative effects of development in floodplain habitat include:

  • Reduced habitat complexity;
  • Reduced prey availability;
  • Modified hydrology;
  • Reduced bank stability;
  • Increased erosion;
  • Increased pollution;
  • Increased water temperature; and
  • Increased risk of downstream wildlife displacement, among others.

Because of the multiple benefits naturally functioning floodplains accrue to communities and the nation, FEMA encourages communities to limit development in floodplains to the degree possible. In addition, as communities implement their floodplain management programs and make development and land use decisions, they must comply with the Endangered Species Act (ESA).

Requirements for Community Floodplain Development

When considering development in the floodplain, communities and developers should ensure they communicate and coordinate with the appropriate National Marine Fisheries Service (NMFS) or United States Fish and Wildlife Service (USFWS) regional or field office. Communities and developers should also take into consideration the following ESA requirements when making land-use decisions:

  • Section 9 of the ESA prohibits the taking of listed species. Take is defined as harassing, harming, pursuing, hunting, shooting, wounding, killing, trapping, capture, or collection of ESA species, or attempting to engage in any such conduct. Harm includes significant habitat modification or degradation that results in death or injury to ESA species by significantly impairing behavioral patterns such as breeding, feeding, or sheltering. Harass is defined as actions that create the likelihood of injury to ESA species to such an extent as to significantly disrupt normal behavior patterns which include, but are not limited to, breeding, feeding or sheltering (50 C.F.R. § 17.3).
  • Section 10(a)(1)(B) of the ESA allows non-federal parties to apply for an incidental take permit for activities that could result in the incidental taking of ESA-listed species. The application must include a habitat conservation plan that describes the proposed actions, determines the effects of those actions on ESA species and their habitats, and defines measures to minimize and mitigate adverse effects. We recommend contacting your local USFWS or NMFS office for assistance with the Habitat Conservation Program permitting process.

For a more complete understanding of all the requirements for development decisions with respect to the ESA, please refer to:

Federal Agency Requirements Under the ESA

Section 7(a)(1) of the ESA requires all federal agencies to utilize their authorities to further the purposes of the ESA by carrying out programs for the conservation of threatened and endangered species. Section 7(a)(2) of the ESA requires all federal agencies to consult with the Services to ensure that any action they fund, authorize, or carry out does not jeopardize the continued survival of any endangered or threatened species or adversely modify designated critical habitat.

FEMA Mapping Processes and ESA Compliance

FEMA requires documentation of ESA compliance before the agency will process a Conditional Letter of Map Revision (CLOMR) or Conditional LFEMA requires documentation of ESA compliance before the agency will process a Conditional Letter of Map Revision (CLOMR) or Conditional Letters of Map Revision Based on Fill (CLOMR-F) application. See the Required Endangered Species Act Compliance Documentation For Conditional Letter of Map Revision Requests webpage for more detailed information and links to guidance on these requirements.