GEOPHYSICAL MONOGRAPH SERIES, VOL. 194, PP. 247-261, 2011
Quantitatively Evaluating Restoration Scenarios for Rivers With Recreational Flow Releases
Department of Geography, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
Department of Biology, Colgate University, Hamilton, New York, USA
Rivers worldwide have been drastically altered in terms of hydrology and morphology. To date, restoration has focused heavily
on channel design (i.e., channel morphology), despite the well-known importance of flow regime on controlling ecological processes.
In addition, there are few quantitative tools with which to directly and quantitatively compare alternative restoration scenarios.
Here we leverage the ecological dominant discharge approach to develop a simple method for quantitatively comparing the effect
of different restoration strategies on an ecological metric, in-stream hydraulic habitat (i.e., limiting depths and velocities
of flow for fish). We apply this approach to the case of a river ecosystem impacted by recreational flow releases. The analysis
shows that enhancing channel morphology will result in limited ecological gains and that greater habitat could be gained through
changes in the hydrologic regime. Greater quantitative tools are needed for directly comparing the potential ecological gains
of different restoration approaches, and these tools should be usable during the initial evaluation stages of a restoration
project; our approach provides a starting point in this direction.
Citation: Doyle, M. W., and