Download 3. Watershed delineation using BASINS 4.0

3.2 Automatic Watershed Delineation using NED and NHD
1. Open the original BASINS 4.0 project. Check the NHD, Cataloging Unit Boundary
and National Elevation layers.
2. Follow steps 2-14 from Section 3.0, substituting the NED dataset for the DEMG
when you select the Base Elevation Data (Figure 3.15).
Fig. 3.15 Automated delineation using the NED grid file.
3. When the two delineations are compared (DEMG and NED), the difference is not
very significant at the large scale (Fig. 3.16). The Brier Creek watershed was divided
into 41 catchments using the DEMG information, and into 39 catchments using the
NED dataset. There are some differences in the values of the various catchment
parameters (e.g. average slope) based on the quality of the datasets.
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