GIS TOOLS INTEGRATING SOURCE WATER PROTECTION WITH CLEAN WATER ACT WATERSHED MANAGEMENT PROGRAMS 42nd America Water Resources Association Conference Session 26: GIS & Modeling Tools for Water Resources Management November 6-9, 2006 Baltimore, MD Authors: William Cooter, RTI International (presenter) James Rineer, RTI International Kevin Pickren, RTI International Sunil Rao, RTI International Scott Guthrie, RTI International Michael Bacon, RTI International Roger Anzzolin, US EPA, Office of Ground Water and Drinking Water

Acknowledgements The work described in this presentation was funded by the U.S. Environmental Protection Agency under Contract 68-C-02-110 with Research Triangle Institute (RTI). RTI gratefully acknowledges this support. Disclaimer: Although the research described has been funded wholly or in part by the U.S. Environmental Protection Agency Contract 68-C-02-110 to Research Triangle Institute, it has not been subject to the Agency's review and therefore does not necessarily reflect the views of the Agency, and no official endorsement should be inferred. Mention of trade names or commercial products does not constitute endorsement or recommendation for use. Disclaimer: In the interest of protecting certain types of information, and in accordance with EPA protocol, the GIS data displayed in the following images were rendered for display purposes only and do not accurately represent actual data from EPA’s spatial databases.

Presentation Outline Overview of the Drinking Water Mapping Application (DWMA) and National Hydrography Dataset (NHD) Area of Investigation approaches to create large area or corridor services using the NHD and the NHDPlus and other vector, raster or remote sensing data Cross-program initiatives linking source water protection goals with management goals of EPA, other federal agency programs, and state programs (e.g., TMDLs, Forest Service programs, and Underground Storage Tanks)

What is the DWMA? A secure, web-based geospatial application for internal use by the US EPA Office of Ground Water and Drinking Water (OGWDW) and other interested EPA staff. Querying and mapping for both surface water and ground water for issues related to source water protection

What is the DWMA? continued Uses information (e.g., intakes) georeferenced to the National Hydrography Dataset (NHD) Performs NHD-based upstream/downstream and proximity analyses Uses Area of Investigation (AOI) data mining tools to process both vector data (e.g., for regulated facilities) and raster data

DWMA Source Protection Areas: Current Approaches Surface water analytical Source Protection Areas (SPAs) Polygon Areas of Investigation (AOIs) constructed around the reaches that fall within 15 miles of a drinking water intake. Convex hulls created in Oracle Spatial. Not a watershed, but a reasonable approximation. Uses the current version of the NHD

Analytical Groundwater Source Protection Areas Wells handled differently, since they extend vertically. Source protection Area defined as simply a 1 mile radius buffer around each of approximately 200,000 wellheads.

SPAs provide Area of Investigation frameworks for analyzing patterns for vector data (e.g., point risks form dischargers or waste sites) and raster data (e.g., land cover information from the NLCD) Percent Impervious Cover indicators can be estimated for each SPA Indicators determined for around 200,000 SPAs related to both surface intakes and wellheads

NHDPlus: Provides Enhancements to the Standard National Hydrography Dataset Improves the utility of the NHD in applications Includes facilities to model water flow and time of travel through the NHD network Provides a set of catchments polygons for each NHD flowpath Can tie datasets or GIS layers related to landscape features (e.g., the National Land Cover Dataset) to the NHD stream network

NHD Catchments can be Aggregated to Match the HUC8/HUC10/HUC12 Polygons in the Watershed Boundary Dataset (WBD) NHD catchments apply the “New England Method” from the USGS New England SPARROW initiative Involves burning NHD flowpath information into the National Elevation Dataset (NED) Provides compatibility between NHD flowpaths (also catchments) and information from Digital Elevation Models (DEMs)

Current SPAs as “hulls” will be upgraded using the NHDPlus Catchments to provide more accurate watershed templates for geospatial analyses

Examples of Area of Investigation Approaches using the NHDPlus Area of investigation frameworks can be generalized to coverage a wide range of target areas: Administrative units (e.g., city boundaries) Highway corridors Natural disaster zones

NHDPlus Upstream/downstream Watershed Envelopes for Administrative Units Urban Boundaries (Salem, Oregon, shown in figure) Federal Lands (e.g., National Forests) National Parks Military Bases Tribal Lands

Highway Corridors

Natural Disaster Zones

Cross-program applications of DWMA features and functionality: some examples Source water protection and TMDLs Waste sites and public lands management Underground Storage Tanks

Source Water Protection and 303(d)/TMDL Crosswalk

Wastesites + TMDLs + Federal Lands + SPAs Bunker Hill “Box” in northern Idaho on the South Fork Coeur D’Alene River

Upstream/Downstream Flowpaths and Catchments from the NHDPlus

Federal Lands in Proximity to the Day’s-Time-of- Travel AOI Watershed for the Bunker Hill NPL Site

Underground Storage Tanks & Source Water Protection Crosswalk

GIS TOOLS INTEGRATING SOURCE WATER PROTECTION WITH CLEAN WATER ACT WATERSHED MANAGEMENT PROGRAMS 42nd America Water Resources Association Conference Session 26: GIS & Modeling Tools for Water Resources Management November 6-9, 2006 Baltimore, MD Contact Information Roger Anzzolin US EPA, OGWDW, Washington, DC anzzolin.roger@epa.gov William Cooter RTI International, RTP, NC sid@rti.org