Stream Centerlines for the Shasta River, CA

To accomplish the objectives laid out in the Summary, several products were developed:

Stream Centerline with Route Index
This product consists of line geometries that were digitized from a combination of data sources. The principle source was an intensity raster produced from LiDAR data collected by Watershed Sciences, Inc., in Feb. 2008. The secondary source was a vector contour set from the contractor-delivered elevation model, which was used to determine the lowest elevations associated with the mapped channel boundary. The river centerline adhered to these two inputs to maintain internal consistency with the LiDAR point cloud.Two center lines were developed; one describes the main stem Shasta River while the other includes the priority reach requested by the Nature Conservancy partners on Big Springs Creek, a tributary to the Shasta River from the east.

Relative Elevation Surface Model
This surface model is a derived elevation model that detrends the river valley by the local water surface elevation. Elevation values on this surface are feet above the modeled WSE, perpendicular to the predominant direction of the river.Four different data elements for this surface are presented. The 100 ft wide stream corridor is presented as an absolute elevation model, the detrended version of the surface, and an analysis layer, which expresses the distance to the assumed hyporheic surface.

Willow Planting Suitability Model
Based on an initial analysis conducted in cooperation with the Nature Conservancy, our assumption is that willow survivorship is maximized when planting occurs within 2.5 ft. of the surrounding water surface elevation (WSE). Thus, the Relative Elevation Surface Model can be used to categorize any given location along the riparian corridor as being suitable, marginal, or unsuitable for willow plantings based on this 2.5 ft. Threshold. However, because the LiDAR-derived elevation model contains a 0.5 ft. Margin of error, the threshold has been adjusted to 2.0 ft. That said, the three categories we used in this analysis are as follows:Recommended: < 2.0 ft. above WSEMarginal: 2.0 ft. - 2.5 ft. above WSEAvoid: > 2.5 ft. above WSE

Vegetation Inventory
The vegetation inventory consists of a geodatabase of vegetation elements (trees) for the tile set. These geometries are created from the classed LiDAR data, and reflect limitations of the classing methods.Due to unstable processing, this tile set is currently missing a number of tiles. These will be updated as soon as the method can be revisited.

Solar Loading Model
Temperature is a limiting factor for ecological health and fish populations on the Shasta River. An inventory of existing vegetation supports modeling the shading contribution of each tree.These vegetation objects include information about density and height from LiDAR return data. These objects also incorporate information summarized on raster grids (canopy height model). Summary of vegetation and canopy as both a continuous surface and discrete objects supports a variety of analyses for landscape prioritization.