Section 1. Short title
This Act may be cited as the Financing Lead Out of Water Act of 2025, or the Flow Act.
(a) In general
Section 141(b)(6) of the Internal Revenue Code of 1986 is amended by adding at the end the following new subparagraph:
(i) In general
For purposes of this subsection, qualified lead service line replacement use shall not constitute private business use.
(ii) Definitions
For purposes of this subparagraph—
(I) Qualified lead service line replacement use
The term qualified lead service line replacement use means, with respect to any public water system, use of the proceeds of an issue to replace any privately-owned portion of a lead service line connected to such system to facilitate, achieve or maintain compliance with a national primary drinking water regulation for lead.
(II) Lead service line
The term lead service line has the meaning given such term in section 1459B(a)(4) of the Safe Drinking Water Act, as amended.
(III) National primary drinking water regulation for lead
The term national primary drinking water regulation for lead means a national primary drinking water regulation for lead promulgated under section 1412 of such Act.
(IV) Public water system
The term public water system has the meaning given such term in section 1401(4) of such Act.
(b) Effective date
The amendments made by this section shall apply to obligations issued after December 31, 2025.