A central problem in the field of stream restoration is that of designing a stable channel thatsupports a healthy benthic population. Many stream restoration projects take place in urban orurbanizing watersheds. The relationship between changing watershed characteristics and localchannel conditions within that watershed is poorly understood. This study is made up of twomajor components that address aspects of this problem: first, a physical study of bedload flux inwatersheds representing rural, urban, and developing conditions and second, verification ofresults from the Computational Hydraulic Engineering Two-Dimensional Sediment Model(CCHE2D) on the reach scale and correlation of CCHE2D results with Rapid BioassessmentProtocol III (RBP III) scores. Study sites were selected in Knox County, Tennessee includingtwelve sites for the bedload study and a single site for the CCHE2D model verification. Thebedload flux portion of the study combines field collection of bedload via portable bedload trapsand an estimate of energy slope from peak stage recorders. Information derived from the fieldcollection will be combined with watershed data via geographic information system (GIS)analysis. Watershed metrics including percent impervious area, roadways adjacent to streams,and average watershed slope determined via GIS will be correlated with the measured bedloadcomposition for each research site. The CCHE2D model verification will combine the study ofbedload flux with a previous study correlating the surficial bed material composition withmacroinvertebrate biotic integrity scores (RPB III) for 76 reaches in East Tennessee. Thecombination of this information will provide a valuable tool in stream restoration design inallowing practitioners to have an empirical metric with which to design/predict channel substratecomposition as an indicator of physical habitat quality.
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