Results of Wetlands Mitigation Associated with Highway Projects (Completed 1995)

Performer(s): FHWA (HEPN-30)
Sponsor(s): FHWA

To order:

Paul Garrett. FHWA, Colorado Div. Office, 555 Zang St., Room 400, Lakewood, CO 80228;
Tel: 303-969-5772 x332; Fax: 303-969-6727; Email: Paul.garrett@fhwa.dot.gov.

Abstract

This research paper was presented at the U.S. Army Corps of Engineers’ Wetlands Symposium held in New Orleans, Louisiana, in April 1995. It analyzes data on wetland mitigation projects carried out for highway projects, collected as part of an FHWA research project, Evaluation of Wetland Mitigation Measures, FHWA-RD-90-083, dated May 1992. The paper evaluates the results of mitigation projects on a no-net-loss basis, considering ecological and socioeconomic functions and values ascribed to wetlands, through two functional assessment techniques, WET and the Hollands-Magee methodologies. Most projects did not meet no-net-loss criteria when functional equivalency was considered, although they may have resulted in an equal area of wetland being created or established. Some projects resulted in the conversion of one wetland type to another, resulting in a net loss of wetland area. Others resulted in a net gain of wetland area, with a replacement of one type of wetland for another (out-of-kind mitigation). Most decisions regarding selection of a mitigation alternative appear to have been based on the availability of an acceptable mitigation site, local wetland management priorities and objectives, or cost.

U.S. 65 Bypass, Pine Bluff, AR — Wetland and Floodplain Mitigation Plan (Completed 1997)

Performer(s): University of Arkansas
Sponsor(s): Arkansas State Highway and Transportation Dept. (AHTD); FHWA ; University of Arkansas

To order:

Bill Richardson. Arkansas State Highway and Transportation Dept., Environmental Div., P.O. Box 2261, Little Rock, AR 72203-2261;
Tel: 501-569-2281; Fax: 501-565-2009; Email: BLRD186@AHTD.State.ar.us.

Abstract

The proposed bypass, consisting of an 11.6-mile four-lane divided highway will be located on new location parallel to Bayou Bartholomew. Approximately 33 acres of wetlands will be filled and converted to highway embankment, and an additional 2 acres will be cleared and allowed to revert to wetlands. Approximately 175 acres of wetlands will be created or restored, and 200 acres of bottomland hardwoods will be purchased and preserved. Innovative mitigation measures resulted in a cost savings of $12 million in construction costs, and demonstrated that design in harmony with nature does not always cost; sometimes it pays. Research funds listed here were budgeted for 43 acres of Nevins Creek wetlands research and mitigation.