Kristina Schneider

kajs@mail.utexas.edu

    For my master’s thesis research I will be focusing on finding a way to use the ArcGIS Hydro Data Model to better integrate data from the National Hydrography Dataset to support TMDL studies. The ArcGIS Hydro Data Model is a GeoDatabase model that the Environmental Systems Research Institute (ESRI) has been developing with the Center for Research in Water Resources (CRWR) at the University of Texas. I will be performing my research at CRWR.  The ArcGIS Hydro Data Model is an essential data model, meaning it does not attempt to describe and model every possible hydrologic occurrence but it captures the concepts that are essential to a hydrographic and hydrologic data model.  It can be used with various datasets and the data model can be modified to fit the needs of each input dataset.

    The National Hydrography Dataset (NHD) is a national set of standardized data for hydrography (the mapping of rivers) developed by the EPA and the United States Geological Survey (USGS). It catalogs the hydrographic features found on USGS topographic maps at 1:100,000 scale and is at the same time also a data model. TMDL is a program developed by the EPA for improving the water quality of the nation’s water bodies. TMDL is the total maximum daily load of a pollutant that should be in a water body. The sources of TMDLs are often non-point source pollutants, which are hard to characterize. The TMDL program hopes to find a way to determine the TMDLs for a water body and then assign these loads using discharge permits to polluters along the water body.  This has already been done in many states but as with any large national program it is an ongoing process.