1. GIS in Watershed Analysis

2. Why watershed Analysis with GIS? Concepts Important datasets Analysis Tools

3. Regional stressors

4. Impacts of Human Activities Stream alterationsAgriculture MiningTimber

5. Watershed based frameworks Integrative approach Legislative roots in the 1972 Clean Water Act –Goal to clean up and protect US water bodies from point and nonpoint sources Designated uses – evaluated as part of the Clean Water Act 2012

6. Watershed cataloging units USGS Regions (2 digit)

7. Watershed cataloging units USGS Sub-regions (4 digit)

8. Watershed cataloging units USGS Sub-basins (8 digit)

9. http://datagateway.nrcs.usda.gov/ NRCS WBD Watershed Boundary Dataset (WBD) HUC 8, 10, 12 and beyond

10. Issues More local watersheds needed One to one relationship between land cover runoff and receiving stream segment Track runoff from land to stream

11. 11 Example of scale differences DNR Stocked streams Tier 2.5 - Reproducing trout streams Impaired streams Watershed boundaries

12. Previous method Delineate watershed boundaries using the topography to guide us

13. Manual method

14. 14 subwatersheds

15. Segment-level watersheds Benefits: –Hydrologically based –Not based on drainage area cutoffs –Not based on management areas –Stream segment by segment –Fully compatible with 1:100K and 1:24K NHD –Networked, based on NHD

16. Existing issue Nesting of watersheds Pass through issues

17. Watershed modeling Segment level watersheds can be used in watershed modeling Also compiled flow tables for each watershed Watershed Schematic: Simplified segment-level watersheds and associated flow table Outlet

18. Geospatial Technologies and Water Resources GTs in watershed management: 1.Elevation surface is key 2.Delineate watersheds 3.Track flow from a point 4.Find intermittent stream paths 5.Calculate drainage areas A valuable tool for water resources management

19. GIS use in the hydro cycle

20. Elevation surface or grid The starting point for all hydrological modeling in GIS USGS Digital elevation model 30m or 10m elevation cells, or 3m for WV Each cell or grid represents a value for the elevation

26. Summary points Watersheds are the key unit of analysis for examining water quality issues Scale issues require us to delineate smaller watersheds for local issues GIS can aid in watershed management by 1.Using elevation grids 2.Delineate watersheds 3.Track flow from a point 4.Find intermittent stream paths 5.Calculate drainage areas

27. Limitations Static snapshot of data Older Elevation grids Only modeling surface interactions

28. Questions / comments?