State highway agencies and the FHWA are charged with the construction, operation, and maintenance of transportation facilities. These facilities may have impacts on wetland systems. To provide safe and efficient transportation facilities while protecting wetlands it is necessary to determine the functions a specific wetland may perform and what the impact of a facility on the wetland may be. Until now there has not been any one method for assessing all of the potential functional values of a wetland. A new assessment method developed by the FHWA considers the functions of groundwater recharge and discharge, flood storage and desynchronization, shoreline anchoring, food chain support, fish and wildlife habitat, and recreation. The FHWA method is a flexible qualitative screening process that uses the U.S. Fish and Wildlife Service (FWS) wetland classification system. The method uses three types of analyses: the threshold analysis evaluates a wetland's relative functional values, the comparative analysis compares the relative values of two or more wetlands, and the mitigative analysis compares the relative costs and benefits of mitigative features. The FHWA method, completed in March 1983, is available to state highway agencies and others concerned with impacts on wetland systems. Instructions on the use of the method are provided through a training course developed for highway agencies by FHWA.

Media Info

  • Media Type: Print
  • Features: Figures; References; Tables;
  • Pagination: pp 17-23
  • Monograph Title: Wetlands and roadside management
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00394936
  • Record Type: Publication
  • ISBN: 0309037514
  • Files: TRIS, TRB
  • Created Date: Nov 30 1985 12:00AM