This line shapefile features stream cross section data from the Russian River mainstem and describes 1999 contours, project limits, tree dripline, DEM breaklines, thalweg and unpaved roads for the Middle Reach. The original source data from which this GIS file was created was contributed to the RRGIS by the Sonoma County Water Agency (SCWA). The Sonoma County Water Agency gathers stream cross section data for the Russian River mainstem on a yearly basis. Comprehensive stream cross sectional information was contributed to the RRGIS for the years 1993 through 2001. Additional cross section data describing conditions as far back as 1990 was at times included in certain files. The contriubted data were in a variety of file formats including .txt , .xls and .dwg. During an advisory meeting with fisheries biologists, it was determined that converting the SCWA cross section data into a GIS formatted file was a high priority for local salmonid recovery planning efforts. This layer can be used for watershed analysis and planning in the Russian River region of California.