Restoration of the Owens River Gorge Ecosystem

In 1991, Los Angeles Department of Water and Power in cooperation with Mono County, California, initiated a multi-year effort to restore the Owens River Gorge. Restoration is focused on developing riparian and aquatic habitat complexity using incremental increases in pulse and base flows. We use pulse flows low enough to prevent erosion of landforms and loss of channel sediments but sufficient to provide seed transport, germination, and hyporheic zone recharge. Monitoring vegetative response shows a large and consistent increase in riparian vegetation each year. Brown trout are responding rapidly to the restoration effort. From zero fish in 1993, brown trout increased by 50 percent between 1995 and 1996. Current trout catch rates of between 7.1 and 5.8 fish/hour demonstrate the success. The key to ecosystem recovery in the Gorge is a multiple-flow regime that allows nature to build and maintain riparian habitat and channel form.