Physical Effects of Wet Weather Flows on Aquatic Habitats - Larry A. Roesner, Brian P. Bledsoe

This study explores the current state of knowledge with respect to the effects of wet weather flows from urban areas on the physical character of aquatic habitat. It identifies knowledge gaps with respect to our ability to define the cause-effect relationships, examines the comprehensiveness of the data used in support of the published literature in the subject area, and makes a qualitative determination of the usefulness of those data for further analysis to increase our knowledge in the subject area. Finally, it recommends further research studies that will increase our knowledge in the subject area, with emphasis on pilot-scale projects that can be used to develop practical protocols for preventing or mitigating the effects.Major findings and conclusions are: 1) we lack a solid conceptual framework for predicting the impact of large-scale watershed modifications and wet weather flows on ecological processes that influence stream communities; 2) there is a need for longer-term monitoring; 3) there is no widely accepted system for quantifying geomorphic instability and degradation of physical habitat; 4) there is a need for process-based stream classification; 5) specific links between urbanization characteristics and stream degradation are lacking; 6) there is a need for urban best management practice (BMP) assessment standards; and 7) developing a multi-scale understanding of habitat potential in human-dominated watersheds is needed. The report recommends a research progra
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