This polyline shapefile depicts data compiled within the nine county San Francisco Bay Area Region, California using the following methods: 1) Using National Hydrography Dataset (NHD) stream data for the entire Bay Area Watershed; we ran zonal statistics using stream segments (unique Reach ID field) as the zone and the 30m DEM elevation as the value raster; 2) Next we took the difference between the maximum and minimum elevations, divided by the length of the stream segment and then multiplied by 100 to get percent slope; and 3) Finally symbolized the data by slope categories - Valley Floors, Foothills and Headwaters - according to what work that the Napa Resource Conservation District has done in Napa County, Fish Ranges by Channel Slope for the Napa River Basin (Koehler 2007). The NHD and the 30m DEM do not match up perfectly. It was not in the scope of the project to do a detailed analysis of stream slope, but rather provide a regional look at how the major stream segments break down into three classes based on the scale of San Francisco Bay Area Upland Habitat Goals Project. This dataset was used during the Fish and Riparian Focus Team to get a better understanding of the slope classes throughout the entire region. This dataset was developed/compiled for use in the San Francisco Bay Area Upland Habitat Goals Project, a Project used to identify a Conservation Lands Network (CLN) for biodiversity preservation to inform conservation investments and lasting cooperative conservation partnerships. The Conservation Lands Network GIS Database is the primary output of the Project. The data depicts the spatially explicit CLN that is recommended for the nine county San Francisco Bay Area Region, California. This layer is presented in the WGS84 coordinate system for web display purposes. Downloadable data are provided in native coordinate system or projection.
