Evaluation of stability threshold analysis as a cursory method of screening potential streambank stabilization techniques

A water quality issue that is of particular concern in human-modified streams is sediment pollution. In-stream areas of sediment production have been targeted and managed using stream channelization and, more recently, biotechnical streambank stabilization. The objective of this study was to evaluate the use of stability threshold analysis as a cursory method to develop a range of potential streambank stabilization techniques for eroding stream reaches. Stability threshold analysis compares permissible velocity and shear stress thresholds to velocity and shear stress values in stream reaches where stabilization is required. Geomorphological data were collected in four reaches of Cazenovia Creek, NY, where bank erosion has been occurring. Lowflow and bankfull flow velocity and shear stress values for each reach were compared with permissible thresholds for several biotechnical bank stabilization methods. Results indicate that stability threshold analysis provides a simple first step towards determining the appropriate type of bank stabilization to use in eroding reaches and that velocity and shear stress values for this study's sites fall within permissible thresholds for biotechnical streambank stabilization methods.