Delineation of the Texas Hill Country Watersheds with Named Streams Team Members: Justin McInnis: Project Manager Matt Anding: Assistant Project Manager Brent Bernstein: GIS Analyst Chris Colman: GIS Analyst

Hill Country Water Resources Clean and adequate water supplies are critical. Water quality is very sensitive to disturbances caused by development.

Hill Country Water Resources Endangered species are also present and must be protected. Texas Blind Salamander (Photograph courtesy of Joe N. Fries, U.S. Fish and Wildlife Service)

Hill Country Water Resources Water quality protection regulations are most effective when based on watershed boundaries, rather than county lines. We will help the Hill Country Alliance in their quest to educate the public regarding these water bodies and watersheds.

Objective Find the names of as many streams possible in the region Delineate watersheds for these streams.

Data 29 Shapefiles of the 29 Sub basins that make up the Hill Country Alliance. This data came from the National Hydrography Dataset which is an extension of the USGS website. These Sub basins are delineated by the streams and rivers that flow in a given area. They were downloaded in High Resolution. Used for stream names

Data Shapefile showing the 17 counties of the Hill Country Alliance. Source: HCA Digital Elevation Model of the Texas Hill Country. Used for the Analysis of the delineation of the Watersheds.

Methodology Data Collection for Stream Names Initial data download from USGS NHD dataset. USGS 7.5’ topographical maps and gazetteers were used to find more stream names. No additional stream names were found. Only NHD data will be given to HCA. It is more data than they previously had.

Methodology Analysis Delineation of Hill Country Watersheds Arc Hydro extensions Use digital elevation models with flow directions Major and Minor Watersheds Defined using the DEM

Fill Sink reconditioned DEM – Filled in any “holes” Flow Direction and Stream Order Methodology

Catchment Polygons created – Delineates each stream’s catchment of water Adjoint Catchment Process attempted – Dissolves polygon lines/ creates watersheds – Did not work

Catchment polygon lines had to be manually merged to produce final product. Methodology

Watersheds for Hays and Kendall Counties were then named.

Final Deliverables Delineation of watersheds for 17 Counties in the Hill Country. Naming of as many streams as possible in the Hill Country area. Naming of watersheds in Hays and Kendall Counties