What is a Wetland?Wetland Delineation / Mitigation

“Those areas that are inundated or saturated by surface or ground water at a frequency and duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil

conditions. Wetlands generally include swamps, marshes, bogs, and similar areas.”

A wetland delineation consists of collection and evaluation of data in accordance with U.S. Army Corps of Engineers’ (Corps) 1987 Wetland Delineation Manual and Regional Supplement to the Corps of Engineers Wetland Delineation Manual.  The process of identifying and locating wetlands is based on determining if an area meets the three criteria including: (1) hydrophytic vegetation, (2) hydric soils, and (3) wetland hydrology.  These parameters are further defined as:

  • Hydrophytic Vegetation: the community of macrophytes (aquatic plants) that occurs in areas where inundation or soil saturation is either permanent or of sufficient frequency and duration to exert a controlling influence on the plant species.
  • Hydric Soils: a soil that formed under conditions of saturation, flooding, or ponding long enough during the growing season to develop anaerobic conditions in the upper part.
  • Wetland Hydrology: hydrology characteristics causing saturation, flooding, or ponding long enough during the growing season to develop anaerobic conditions.  This can be identified by observation of surface water or saturated soils, evidence of recent inundation (water marks, drift deposits), evidence of current or recent soil saturation, or other (gauge data).

Why is it Important to Identify Wetlands?

Wetland Delineation / MitigationSection 404 of the Clean Water Act requires that anyone interested in depositing dredged or fill material into "waters of the United States, including wetlands," must receive authorization for such activities. The US Army Corps of Engineers has been assigned responsibility for administering the Section 404 permitting process.

Activities in wetlands for which permits may be required include, but are not limited to:

  • Placement of fill materialWetland Delineation / Mitigation
  • Ditching activities when the excavated material is sidecast
  • Levee and dike construction
  • Mechanized land clearing
  • Land leveling
  • Road construction
  • Dam construction

The final determination of whether an area is a wetland and whether the activity requires a permit must be made by the appropriate Army Corps of Engineers District Office.  Our professionals have extensive experience in producing wetland reports for the Corps of Engineers and other governmental agency review. The large majority of these reports have been used to complete permit application submittals to the Corps of Engineers or other regulatory agencies.