Biologists rated each Calwater (California Watershed Map) Hydrologic Sub-area (HSA) based on occupancy and habitat quanitity and quality information found in the Steelhead distribution shapefile (CCV_Steelhead_Draft_2004). These biological ratings were compared against economic values given to each HSA. Based on whether selected criteria were met, an HSA was determined to be included or excluded from Critical Habitat. All stream segments were then coded to reflect their HSA's designation. The only exceptions to this occured when a stream segment was valued as a migration corridor (the segment would be included as Critical Habitat even if the HSA was excluded) or if there were other overriding biological considerations.
Those segments coded as Critical Habitat were then extracted from the distribution shapfile and placed in the resulting 'CCV_Steelhead_Proposed_Critical_habitat' file. Public comments were received following draft publication of the Critical Habitat Proposed Rule in December 2004. These comments were incorporated into the data set and the final critical habitat file 'CCV_Steelhead_CH_06_2005' was created.