WETLAND MITIGATION EFFECTIVENESS - DEVELOPMENT OF COST-EFFECTIVE METHODS AND PROCEDURES FOR KANSAS

In the last decade, efforts to create and restore wetlands have expanded in response to both increased awareness of wetland benefits and changes in governmental policy. By some estimates half of the United States' original wetlands have been destroyed. Remaining wetlands are valuable for floodwater management, water quality and wildlife habitat as well as aesthetic and educational benefits to humans. Section 404 of the Clean Water Act (1987) requires mitigation of wetlands that will be destroyed, and is enforced by the U.S. Army Corps of Engineers. For any wetland to be developed, a dredge and fill permit must be obtained, and a wetland creation or enhancement must occur to compensate for the wetland to be impacted. In national regulations for wetland delineation, the U.S. Army Corps of Engineers defines wetlands as: "Those areas that are inundated or saturated by surface or groundwater 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." In both delineating and restoring or creating wetlands, it is essential to focus on three parameters: hydrology, wetland soils, and wetland vegetation. Monitoring of wetland mitigations is necessary to ensure that the wetlands' criteria are met and the wetland is functioning as planned. At the time of planning, mitigation goals should be set based on hydrological criteria, soil and vegetation. These criteria are best established when based on local wetland ecology and careful consideration of the impacted wetland. To ensure success, monitoring should be conducted from the time of construction until the mitigation goals and criteria are met. A detailed look at the vegetation of wetland mitigations can determine its ability to sustain wetland status into the future. Measurement of soil characteristics can help determine the site's ability to maintain hydrology and the vegetation necessary for continued wetland development. The hydrology of each mitigation site should be analyzed based on mitigation project objectives. This does not infer a complete design type analysis, but instead a reconnaissance study of the existing hydrologic conditions over time and under a variety of weather conditions to determine if the mitigation is able to support the planned, long term objectives of each mitigation project. The objective of this study was to examine wetland status, success rate, and the potential for continued development as wetlands of six Kansas Department of Transportation (KDOT) wetland mitigations. The wetlands were constructed to compensate for impacts caused by KDOT road projects in accordance with the Army Corps of Engineers 404 permit process. At each mitigation the vegetation, soils, and hydrology were studied to assess the site's current and future ability to function as a wetland. Each site was monitored for the presence of wetland parameters, and the results were analyzed in the context of long-term site goals and objectives.

Language

  • English

Media Info

  • Features: Appendices; References;
  • Pagination: 52 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00800199
  • Record Type: Publication
  • Report/Paper Numbers: K-TRAN: KU-96-2,, Final Report
  • Contract Numbers: C-894
  • Files: TRIS, STATEDOT
  • Created Date: Oct 13 2000 12:00AM