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WATERS Web Services


WATERS provides a suite of interoperable services that expose components that perform complex analysis and supporting strategic datasets, such as NHDPlus and the Reach Address Database.

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Web and Database Services

The WATERS Web and Database services provide open interfaces to complex analyses. These services make extensive use of NHDPlus and referenced program data in the Reach Address Database, and also integrate other WATERS program data. Designed as loosely coupled modular units, the services are developed in a common architecture.

The WATERS Database Services require users to be on the EPA network and to have a TSMSS ID and schema password. Database Services provide users with the advantage of deploying applications within EPA that can take advantage of direct database call functionality.

Service Name HTTP Service Database Service
Event Indexing Service
The Event Indexing Service allows users to dynamically index features against NHDPlus hydrology to create RAD-ready events.
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Point Indexing Service
Service providing point indexing via distance or NHDPlus flow direction raindrop indexing to NHDPlus features.
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Name Service
Advanced query function to find water feature names and provide general location information for NHDPlus features.
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Upstream/Downstream Search Service
The Upstream/Downstream Search service is designed to provide standard traversal and event discovery functions upon the NHDPlus stream network.
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Navigation Service
The Navigation service provides standard stream traversal on the NHDPlus stream network.
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Navigation Delineation Service
Service providing basin or other feature type delineation based upon navigation results.
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RAD Event Info Service
Service providing detailed information on Reach Address Database events.
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Lookup Services
Query services returning small non-spatial result sets of WATERS data.
Results Queue Service
Service for managing asynchronous processing of other WATERS services.
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Spatial Assignment Service
Service providing spatial interaction information for a given geometry using various layers within WATERS.
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Mapping Services

WATERS mapping services provide access to feature layers via ESRI and Open Geospatial Consortium Exitservice formats. Users can consume WATERS datasets using client applications such as ArcGIS Desktop, Bing Maps, Google Maps, Leaflet, Google Earth and/or ArcGIS Explorer. Developers can utilize these services to incorporate WATERS feature layers into their own mapping applications. Specific information about the mapping services are documented on the WATERS Mapping Services web page.

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Mailing List

WATERS provides an opt in/out mailing list which allows partners to stay informed about announcements related to WATERS. Announcements include but are not limited to new service offerings, changes to existing services, etc. If you would like to join the mailing list, please send an e-mail to or use the Contact Us web page.

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Terms of Use and Disclaimer

The user is responsible for reading and evaluating dataset limitations, restrictions, and intended use. For additional information, please see WATERS Terms of Use and Disclaimer.

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Web Services Decommissioned: January 31, 2014

  • Validate Lat/Long Service
  • Convert Lat/Long Service
  • Get Entities by Lat/Long Service
  • Get Entities By Huc Service
  • Get Entities Miles By Lat/Long Service
  • Get Program Waters Entities
  • Identify Service
  • Total Waters Service
  • Total Waters Geometry Service 

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