The 1996 amendments to the Safe Drinking Water Act (SWDA), established the Drinking Water State Revolving Fund (DWSRF). The SDWA also authorized EPA to set-aside up to 1.5% of the DWSRF for grants to improve the infrastructure of drinking water systems that serve tribes (SDWA §1452i). Starting in 2010, Congress increased the tribal set aside funds to 2%. Through this authority, EPA established the Drinking Water Infrastructure Grants Tribal Set-Aside (DWIG-TSA) Program. Community water systems and non-profit, non-community water systems that serve a tribal population are eligible to have projects funded, in whole or in part, with DWIG-TSA funds.

The 2016 Water Infrastructure Improvements for the Nation Act (WIIN Act) expanded the activities that are now eligible for DWIG-TSA funds, to include training and operator certification programs.

The 2021 Bipartisan Infrastructure Law provided a historic $15 billion in dedicated funding through the DWSRF and DWIG-TSA appropriation for lead service line identification and replacement and $4 billion in dedicated funding for addressing perfluoroalkyl and polyfluoroalkyl substances (PFAS) and other emerging contaminants.

For this opportunity, funds can be used only for planning and construction expenditures at community or non-profit non-community drinking water systems that serve tribes. Funds must be used to address the most significant threats to public health.

These funds cannot be used for compliance monitoring, operation, and maintenance of a system.

Examples of projects funded by the DWIG-TSA Base funding program are:

• Rehabilitation or development of sources of drinking water;
• Installation or upgrade of treatment facilities;
• Installation or upgrade of storage facilities;
• Installation or replacement of transmission or distribution pipes; or
• Replacement of aging water system infrastructure.
• Projects can also be funded to develop project engineering reports, engineering design work and project administration.