An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to www.epa.gov. This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »

WATERS Tools

Waters watershed assessment tracking environmental results system
  • Ask WATERS
    Ask WATERS answers multi-program questions that draw on information from the databases linked through WATERS. This tool generates cross-program calculations, examines spatial relationships between programs, and performs nationwide analyses. Ask WATERS includes both a Simple and Expert Query Tool. The Simple Query Tool provides built queries of frequently asked questions that a user may run for a State, Region, or the Nation. The Expert Query Tool is a web-based application that allows a user to create their own queries to display or extract data concerning impaired and assessed waters and associated, approved Total Maximum Daily Loads.
  • How’s My Waterway
    How's My Waterway was designed to provide the general public with information about the condition of their local waters based on data that states, federal, tribal, local agencies and others have provided to EPA. Water quality information is displayed on 3 scales in How’s My Waterway; community, state and national.
  • NHDPlus Tools
    NHDPlus Tools is a collection of ArcGIS extensions provided to assist in the understanding and use of NHDPlus data and in the development of NHDPlus applications and tools.
  • Nitrogen and Phosphorus Pollution Data Access Tool (NPDAT)
    The EPA Nitrogen and Phosphorus Pollution Data Access Tool (NPDAT) is a Web-based tool intended to help states develop effective strategies for reducing nitrogen and phosphorus pollution. The NPDAT consists of an introductory website, geospatial viewer, and data download tables.
  • HEM Tool
    The Hydrography Event Management (HEM) Tool is now available to create NHD events for various EPA programs. Click to learn more about the HEM Tool.
  • Viewing WATERS Data using Google Earth (WATERS KMZ)
  • WATERSKMZ is a compressed Keyhole Markup Language (KML) file that provides users with easy access to geospatial WATERS data and services using Google Earth.
  • WATERS Web Services
    The WATERS web services are database and web based services providing user application friendly interfaces to complex analyses. These services make extensive use of the NHD and indexed program data in the RAD, and also integrate other WATERS program data in selected services. Designed as modular units, the services are being developed within a common architecture and each service will become available as it is completed and tested.
  • WATERS GeoViewer
    WATERS GeoViewer is a web mapping application which allows users to view data and execute web services provided by the US EPA Office of Water’s Watershed Assessment, Tracking & Environmental Results System (WATERS).