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WATERS (Watershed Assessment, Tracking & Environmental Results System)

The Watershed Assessment, Tracking & Environmental Results System (WATERS) unites water quality information previously available only from several independent and unconnected databases. 

Basic Information

Watershed Assessment, Tracking and Environmental Results

The data architecture of WATERS integrates information from various EPA water programs by linking it to the national surface water network. For EPA, the surface water network is based on the NHDPlus dataset which incorporates the best features of the National Hydrography Dataset (NHD) Exit, the National Elevation Dataset (NED) Exit, and the Watershed Boundary Dataset (WBD) Exit. The integration of water program data using NHDPlus improves communication and efficiency which empowers EPA to meet its goals under the Clean Water Act.

Using WATERS, environmental professionals and interested citizens can access comprehensive information about the quality of the nation's surface water. Available information includes but is not limited to:

  • designated use(s) of a waterbody;
  • water quality monitoring results;
  • assessments of water quality;
  • causes and sources of impaired waters;
  • public beach closures; and
  • location of dischargers.

Get Data/Tool

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 Mapping Services

WATERS exposes several mapping services that provide access to numerous datasets.

Learn More