PRIA Logo™
MontanaHB 66469th Legislature, Regular Session (2025)House

Repeal numeric nutrient standards

Sponsored By: Bill Mercer (Republican)

Signed by Governor

Environmental ProtectionState GovernmentWaterRule Making

Personalized for You

How does this bill affect your finances?

Personalize government policy and PRIA will tell you what this bill means for your household, plus every other piece of legislation we track. PRIA reads each provision against your financial profile to show you exactly what matters to your wallet.

Free to download

Bill Overview

Analyzed Economic Effects

3 provisions identified: 1 benefits, 0 costs, 2 mixed.

Numeric nutrient standards repealed, new rules

The law repeals DEQ-12A, Montana’s numeric nutrient standards. DEQ deletes all references to DEQ-12A in ARM 17.30.507, 17.30.516, 17.30.602, 17.30.619–17.30.629, 17.30.702, and 17.30.715. It also repeals ARM 17.30.660 and 17.30.1388 and removes the old transition statute, 75-5-321. DEQ now sets nutrient criteria by rule under Title 75, chapter 5, part 3. The law takes effect on passage and approval.

New pollution and mixing zone definitions

The law says groundwater contamination inside a permitted CO2 storage reservoir is not “pollution.” It also says certain contamination does not get a mixing zone. These changes alter permit and enforcement rules for the affected discharges.

Watershed advisory groups replace workgroup

The law removes the Nutrient Work Group from statute. DEQ no longer uses that group for advice on nutrient rules. Instead, watershed advisory groups advise DEQ on the impaired-waters list and TMDLs under 75-5-702 and 75-5-703.

Sponsors & Cosponsors

Sponsor

  • Bill Mercer

    Republican • House

Cosponsors

  • John Esp

    Republican • Senate

Roll Call Votes

All Roll Calls

Yes: 207 • No: 91

Senate vote • 4/15/2025

Do Concur

Yes: 34 • No: 16

Senate vote • 4/14/2025

Do Concur

Yes: 34 • No: 16

House vote • 3/7/2025

Do Pass

Yes: 69 • No: 30

House vote • 3/6/2025

Do Pass

Yes: 70 • No: 29

Actions Timeline

  1. Chapter Number Assigned

    5/5/2025House

  2. Signed by Governor

    5/1/2025House

  3. Transmitted to Governor

    4/24/2025House

  4. Signed by President

    4/24/2025Senate

  5. Signed by Speaker

    4/23/2025House

  6. Returned from Enrolling

    4/18/2025House

  7. Sent to Enrolling

    4/15/2025House

  8. 3rd Reading

    4/15/2025Senate

  9. 2nd Reading

    4/14/2025Senate

  10. Committee Report

    4/10/2025Senate

  11. Committee Executive Action

    4/9/2025Senate

  12. Hearing

    3/27/2025Senate

  13. Referred to Committee

    3/17/2025Senate

  14. 1st Reading

    3/14/2025Senate

  15. Transmitted to Senate

    3/7/2025House

  16. 3rd Reading

    3/7/2025House

  17. 2nd Reading

    3/6/2025House

  18. Committee Report

    3/1/2025House

  19. Committee Executive Action

    2/28/2025House

  20. Hearing

    2/24/2025House

  21. 1st Reading

    2/22/2025House

  22. Referred to Committee

    2/22/2025House

  23. Introduced

    2/22/2025House

Bill Text

  • Enrolled

    4/16/2025

    PDF

  • Introduced

    2/22/2025

    PDF

Related Bills

Back to State Legislation