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Clean Watersheds Needs Survey (CWNS) – 2004 Report and Data

The 2004 CWNS summarizes the results of EPA's fourteenth national survey on pollution control capital investment needed to meet environmental and human health objectives of the Clean Water Act. The information helps Congress, state legislatures, communities and others make informed investment decisions about clean water infrastructure and pollution control methods.

Report to Congress and Summary of Results

The 2004 CWNS estimates that nationwide capital investment needs for wastewater pollution control is $202.5 billion. This amount includes:

  • $134.4 billion for wastewater treatment and collection systems;
  • $54.8 billion for combined sewer overflow corrections; and
  • $9.0 billion for stormwater management.

Small communities have documented needs of approximately $17.0 billion.

The increase in overall national needs from the 2000 CWNS estimates is due to a combination of population growth, more protective water quality standards, and aging infrastructure.


CWNS 2004 Data Detail

  • 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.
  • Ask WATERS Expert Query Tool – Search and filter data within user selected tables (e.g. "Needs", "Flow"). Results are delivered in a tabular report and can be downloaded in CSV or HTML format.
  • CWNS 2004 Data File (ZIP)(1 pg, 20 MB)  - Download the Microsoft Access database to select data across multiple tables. The Microsoft Access database is contained within the downloadable ZIP file. Open the ZIP file to access the database.

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