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Clean Water State Revolving Fund (CWSRF): Decentralized Wastewater Treatment

Decentralized wastewater treatment is an onsite or clustered system used to collect, treat, and disperse or reclaim wastewater from a small community or service area (e.g., septic systems, cluster systems, lagoons).

CWSRF-eligible decentralized wastewater treatment projects include:

  • Upgrade (e.g., nutrient removal), repair, or replacement of existing systems;
  • Construction/installation of new systems; costs associated with the establishment of a responsible management entity (RME) (e.g., permitting fees, legal fees, etc.); and
  • Septage treatment works and pumper trucks to support the proper maintenance of decentralized systems.

Funding Decentralized Wastewater Treatment Systems with the Clean Water State Revolving Fund
This fact sheet demonstrates how the CWSRF provides assistance to eligible recipients for decentralized wastewater treatment system projects. It highlights successful decentralized wastewater treatment programs in Rhode Island and Alabama.

Decentralized Systems: Developing Partnerships to Broaden Opportunities Using the CWSRF
Many states maximized the effect of their CWSRF ARRA grant by partnering with other state agencies, local governments, and nonprofit organizations to manage a large number of projects to repair and replace failing onsite treatment systems which ensured cleaner water for their states.

Success Story

Decentralized Wastewater Treatment: Ohio’s Home Sewage Treatment System Program
Ohio’s CWSRF program provided over $3 million in ARRA funds to decentralized wastewater projects as part of its Home Sewage Treatment System program.

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