Literature Review of Rock Revetment and Channelization Impacts on Pacific Northwest Aquatic Resources

We collected peer-reviewed and grey literature related to rock (rip-rap) revetment and channelization impacts to aquatic organisms. In general, the literature reflected agreement that the impacts of channelization (with or without rock revetment) are severe and long-lasting, often reducing fish populations and habitat to levels significantly below those prior to construction. The effects of rip-rap alone on fish populations were less clear; although some studies show that rock revetments reduce and degrade natural bank features, other research outlines the use of rip-rap in stream restoration projects to provide constructed habitat features in channelized rivers. Recognizing the inherent impacts associated with these types of construction projects, and reviewing the accepted conventions for impact reduction, are very important for inclusion into future planning efforts.