The Cochran Restoration Site is located near the town of Franklin in the western mountains of North Carolina. The entrenched streams suffered from significant bank stress, bank erosion, poor habitat and water quality. Past agriculture practices included the relocation of the channel to the edge of the valley and construction of ditches to drain the floodplain. Ditching and grading activities reduced jurisdictional wetland to less than 1 acre from a historical extent of over 4 acres. Soils investigations revealed buried hydric soils beneath approximately 12 inches of alluvial deposits.
The goal of the project was to restore ecological function to the existing stream and riparian wetlands by returning the Cochran Branch to a proper relationship with the floodplain. The stream was constructed as a type C4 stream throughout most of the project length with the upper reach constructed as a type B4 stream.
Cochran Branch has a drainage area of 1.25 square miles and was constructed with a bankfull width of 15 feet and a width/depth ratio of 17. Installation of brush, rock and wood structures were used to enhance channel stability and increase habitat diversity. Restoration efforts also involved re-composition of the stream bed using native on-site bed material. Restoration of the adjacent wetlands required removal of legacy sediments to expose the buried ‘A’ horizon and hydric soils. Additional restoration activities included eliminating the floodplain drainage ditches, removal of invasive species, and replanting the riparian area with native plant species appropriate for the valley and watershed conditions.
The Cochran Branch Site was developed as a full delivery mitigation site by Resource Environmental Solutions (RES) for the North Carolina Division of Mitigation Services. Wolf Creek Engineering provided design and construction oversight for the restoration of 1,800 feet of streams and 4.35 acres of wetlands. Construction was performed by North State Environmental, Inc. and was completed in 2015.
5 months after restoration
Aerial photos 5 months after restoration