1984, 1985, 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, and 2002. California Geological Survey. This line shapefile depicts channel classifications, including Rosgen classes and other descriptors of stream channel and valley characteristics, w... California Geological Survey.