In-stream Restoration Measures

Human-induced disturbances brought about by land use activities introduce changes to the ecological structure and function of stream corridors. Flood-control structures, channel modifications, forest management, road building, agricultural tillage, and urbanization can have dramatic effects on the geomorphic and hydrologic characteristics of stream corridors and the associated uplands. For example, streams are often straightened or moved for more efficient agricultural production or to accommodate increased runoff.

Stream corridors are also often modified to enhance conditions for single purposes, such as fish habitat, or to manage localized streambank erosion. Some of the potential effects caused by these changes are impaired upland or floodplain surface and subsurface flow; increased water temperature, turbidity, and pH; incised channels; lower ground water elevations; streambank failure; and loss of habitat for aquatic and terrestrial species. In-stream restoration techniques include pond and dam removal, rock vanes, double-wing deflectors, constructed riffles, boulder clusters, and sinuosity restoration.

Restoration Projects: Before & After

 

riffles before 

 

riffles after 

Big Bone Creek, Big Bone Lick State Park, Boone County, KY:  Before and after stabilization of stream exhibiting headcuts, incisions, a breached dam, and other impairments. Primary stabilization techniques was by dam removal and construction of rock riffles.

 

woodland hills before 

 

woodland hills after 

Moock Road Creek, Woodland Hills Condominium Complex, Campbell County, KY:  A migrating outside bend was threatening a road at the top of the bank on 100 feet of channel. Construction of two rock vanes diverts flow away from the bank, lessens bank steepness, and improves safety of the road.

 

seymour before 

 

seymour after 

Seymour Creek, Hamilton County, OH:  Before and one year after construction of five rock vanes to divert impinging flow away from the outside bend. Flow diverted away from toe of slope to center of channel, improving vegetation and water quality.