CWNS Basics
The CWNS is a comprehensive assessment of the capital needs to meet the water quality goals set in the Clean
Water Act. Every four years, the states and EPA collect information about:
- Publicly owned wastewater collection and treatment facilities
- Stormwater and combined sewer overflows (CSOs) control facilities
- Nonpoint source (NPS) pollution control projects
- Decentralized wastewater management
- Estuary management projects
Information collected about these facilities and projects includes:
- Estimated needs, including costs and technical information, to address a water quality or
water-related public health problem
- Location and contact information for facilities and projects
- Facility populations served, flow, effluent, and unit process information
- NPS best management practices
This information is used by EPA to document national needs in a
Report to Congress. The Report provides Congress, as well as state legislatures, with
information to assist their budgeting efforts. The data are also used to:
- Help measure environmental progress
- Contribute to academic research
- Provide information to the public
- Help local and state governments implement water quality programs
Within EPA, the CWNS supports the
Office of Water's Sustainable Water Infrastructure (SI) Initiative.
Through the SI Initiative, EPA is working with the water industry to help identify best practices
that have helped many of the nation's utilities address a variety of management challenges
and extend the use of these practices to a greater number of utilities. The four priority
areas, or pillars, are: Better Management, Full Cost Pricing, Watershed Approach, and
Water Efficiency. The CWNS supports this initiative by:
- Encouraging advanced assest management by emphasizing 20-year needs, including
gathering basic pipe inventory and replacement schedule data
- Helping to assess the degree of adoption and implementation of various voluntary utility
management programs by facilities
- Collecting more current and complete treatment technology data
- Providing useful data to inform watershed approaches to water quality protection