Stillwater Sciences is supporting the Sacramento Municipal Utility District in its relicensing of the Upper American River Project, a large, multi-reservoir, multi-powerhouse hydroelectric project. Stillwater Sciences completed the Aquatics and Geomorphology sections of the Initial Information Package, which documents existing data sources and provides a baseline description of environmental conditions. Study plans were developed for fisheries, stream and reservoir habitat, instream flows, geomorphology, aquatic macroinvertebrates, entrainment, migration barriers, and amphibians. Field studies have been completed for fisheries, including electrofishing and snorkel surveys in the streams, and seining and gill netting of the reservoirs. Project bypass reaches have been habitat-mapped, either from the ground or using low-level aerial videography. Reservoir fish habitat studies have been completed, and the data used with a GIS to assess fish habitat changes in response to fluctuating reservoir elevations. Instream flow studies have been conducted at 11 study sites, and weighted usable area versus flow relationships developed, in addition to a time series analysis. Geomorphology studies to date include Rosgen Level 1 channel classification of over 50 miles of stream, and Rosgen Level 2 and 3 assessments of 16 study sites. Specifically, these geomorphology studies have included characterizing bed surface particle size (by means of Wolman pebble counts) and fine sediment accumulation (by means of V* measurements). Sediment transport issues are being addressed at four of these study sites. Aquatic macroinvertebrates have been sampled at over 30 sites using the California Stream Bioassessment Procedure. Visual Encounter Surveys for amphibians and aquatic reptiles have been completed at several potential study sites in each reach based on a number of physical habitat parameters including extent of riparian vegetation, channel gradient, and substrate. Amphibian and reptile species of concern include California red-legged frog, foothill yellow-legged frog, mountain yellow-legged frog, Yosemite toad, and western pond turtle. Aquatic and other studies are conducted under the guidance and approval of a multi-agency technical work group and major stakeholders as part of a collaborative alternative licensing process.

Key issues that Stillwater is addressing include minimum flows in the bypass reaches, fish population and ecosystem health, and sediment transport needs. Field studies were completed in 2004, and technical report and NEPA document preparation will continue into 2005.