>> See the 2005 "Flows and recreation" guide, a full publication on this issue.
Instream flow—the amount of water in a river or stream—has a profound influence on the type and quality of river recreation opportunities. A substantial literature addresses the short and long-term flow requirements for fisheries, aquatic habitat, riparian communities, geomorphic features, or other biophysical attributes (Hill et al. 1991, Richter et al. 1997, Tharme 2002), all of which can affect recreation (Whittaker et al. 1993). A smaller but developing literature on flows for recreation more commonly focuses on “immediate” rather than long-term effects (Brown et al. 1991, Whittaker et al. 1993, Whittaker and Shelby 2002, Whittaker et al. 2006). Most of this work addresses whitewater boating, although some studies have examined flow effects on general recreation (Narayanan 1986, Duffield et al. 1994), swimming (Whittaker and Shelby 2001), availability of beaches (Shelby et al. 1992), in-channel “slot canyon” hiking (Shelby et al. 1997), or general river aesthetics (Whittaker and Shelby 2002).
Most flow-recreation studies in relicensing settings use on-site assessments by panels of experienced users (e.g. boaters or anglers), particularly when flows can be experimentally controlled. However, there are many other ways to examine these issues depending upon the river’s characteristics.
The following report provides a complete evaluation of the scientific approaches to evaluate the effect of hydroelectric dams on recreation opportunities.
