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Clean Watersheds Needs Survey (CWNS) – 2012 Report and Data

The CWNS estimates the capital investment necessary for publicly owned treatment works (POTW) to address the water quality objectives of the Clean Water Act (CWA). The 2012 CWNS is the sixteenth survey since the enactment of the CWA in 1972 which requires this Report under section 516(b)(1)(B) (33 U.S. Code §1375).

Report to Congress and Summary of Results

The total capital wastewater and stormwater treatment and collection needs for the nation are $271 billion as of January 1, 2012. This includes capital needs for publicly owned wastewater pipes and treatment facilities ($197.8 billion), combined sewer overflow (CSO) correction ($48.0 billion), stormwater management ($19.2 billion), and recycled water treatment and distribution ($6.1 billion).

View the following 2012 Clean Watersheds Needs Survey documents:

  • CWNS 2012 Report to Congress
  • Report to Congress Fact Sheet
  • CWNS 2012: Detailed Scope and Methods

View State Fact Sheets for summaries of needs, number of facilities, and population served, by state. 

Access to Detailed Data

EPA provides a concise printed version of the CWNS 2012 Report to Congress and additional online data visualization tools. These online tools allow users to view, analyze, download specific data, and print individual state and facility level data:

  • Data Dashboards - Display select multi-level CWNS data for chosen geographic areas in bar graphs and pie charts.
  • CWNS Mapping Tool - GIS-based interactive mapping tool to drill down to get state, congressional district, county and facility level CWNS data.
  • Facility/Project Fact Sheet – Shows CWNS data available for an individual wastewater treatment plant, collection system, stormwater management facility, decentralized wastewater management project, or nonpoint source pollution prevention project.
  • Summary Reports - Display selected CWNS data for geographic areas in bar graphs and pie charts.
  • Detailed Reports - Display selected CWNS data for chosen geographic areas. The output is displayed in tables which can be exported as csv files.
  • Technical Data Reports - Display data that was previously included in the appendices of the Report to Congress. These data tables are comparable to those found in Appendix I of the CWNS 2008 Report to Congress.
  • Data Download - Downloadable Microsoft Access database of all CWNS data elements for the nation or a selected state.

Related Resources

  • Data User's Dictionary - Provides definitions of data elements available in the CWNS summary reports, detailed reports, and Access database.
  • Reports Help - Provides information about how to create and use CWNS online reports.