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Basic Information


The Watershed Assessment, Tracking & Environmental Results System (WATERS) was developed in partnership with states, territories and tribes to improve communication about the quality of the Nation's surface waters.

WATERS is built on a data architecture that integrates information from various EPA Office of 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), the National Elevation Dataset (NED), and the Watershed Boundary Dataset (WBD).  The integration of Water Program data using NHDPlus improves communication and efficiency which empowers EPA's Office of Water 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
  • location of dischargers

The following high-level picture illustrates how various program databases are linked together using the Reach Address Database (RAD) to support various applications and services.

Diagram display of how the RAD interacts with other databases, applications and services.

The process of linking program database information to the National Hydrography Plus dataset is explained on the Geography of WATERS webpage.  

Additional technical information about WATERS is available from the WATERS documentation webpages.


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