California Redwoods Region - Number of Road and Stream Crossings (by Watershed)

This dataset represents the estimated number of road and stream crossings per watershed compiled by the Conservation Biology Institute for the report "A GIS-based model for assessing conservation focal areas for the redwood ecosystem." For more details, see the full report at http://consbio.org/products/reports/a-gis-based-model-for-assessing-conservation-focal-areas-for-the-redwood-ecoregion. We are certain that not all existing roads and streams were accounted for on the U.S. Geological Survey 7.5 minute quadrangle products we had access to (both electronic and paper form). Dates on these quadrangles covered approximately a 30year time span (late 1960s to late 1990s) and some were still in their provisional state. In spite of this serious shortcoming, we still feel that we have captured enough of the data to make this initial assessment. Hopefully, the deficiencies that do exist are distributed somewhat uniformly across the region -- we have no way of knowing at this point. Another issue pertains to road/stream arrangement in more highly developed areas. For some of the more developed watersheds, a low road/stream intersection score does not necessarily reflect potential level of disturbance as we intended. In these areas, some of the minor watercourses have been altered significantly, sometimes in dramatic ways (e.g., burying stream segments under development projects) adding a level of complexity not originally expected. There are a handful of watersheds that were affected in this way in the redwoods. There were so few affected that we did not demote these watersheds in the model, but that could be done in future applications for this or other locations.