Stream Restoration Using a Natural Channel Design Approach

James W. Gracie
10301 Wetherburn Road, Ellicott City, Maryland 21042; Phone 410-418-8476 FAX 410-418-8479 Email: jgracie@holonet.net

In recent years there has been a growing interest in restoring the physical integrity of streams that have been damaged by impacts from land use changes. An approach that has been found to have merit is one using a design approach based upon natural, stable stream channels. This paper will summarize the necessary steps required to accomplish restoration using the natural channel design approach from identifying the potential versus the current state, estimating the design discharge, finding appropriate stream types to fit the valley morphology, and finally matching the dimensionless ratios of stable streams of the same type from equivalent hydrophysiographic regions. Examples of restoration projects including information on the response of aquatic life to the beneficial changes effected by restoration are given. Finally, some observations on the strengths, limitations and pitfalls inherent in this approach are given.