# Montana HB 180: Revise sanitation in subdivision laws related to mixing zones

Montana HB 180, Revise sanitation in subdivision laws related to mixing zones, is a 69th Legislature, Regular Session (2025) House bill sponsored by Courtenay Sprunger (Republican); status signed, last action 2025-05-05 (Chapter Number Assigned) (as of 2026-10-19).

- Canonical: https://policyrisk.com/state-bill/MT-HB180-2025
- As of: 2026-10-19
- Plain-text twin of the page above; the HTML and this file carry the same facts.

## Facts
- Bill: Montana HB 180
- State: Montana
- Session: 69th Legislature, Regular Session (2025)
- Title: Revise sanitation in subdivision laws related to mixing zones
- Status: signed
- Chamber: House
- Introduced: 2025-01-13
- Last action: 2025-05-05, Chapter Number Assigned
- Sponsor: Courtenay Sprunger (Republican)
- Cosponsors: 1
- Subjects: Planning, Water, Counties, Environmental Protection, Local Government
- Touches household money: no
- Roll calls: 4 (297 yes, 0 no in all)
- Economic provisions PRIA read: 2

## Summary

No summary available.

## Bill overview: provisions PRIA read

- Uniform septic variance rules and appeals: benefit, low. Local health boards must use the same standards as the state Department of Environmental Quality when deciding sewage variances. If the board denies or conditions your variance, you can appeal to DEQ. This creates a single, clear process across counties.
- Stricter septic and well setback rules: mixed, medium. The law tightens where new septic drainfields and wells can go near property lines. For parcels created after March 30, 2011, local health boards must deny a septic system if its mixing zone would cross onto a neighbor’s land, unless a narrow state-law exception allows it. Where local boards permit…

## Sponsors and cosponsors

- Sponsor: Courtenay Sprunger (Republican), House
- Cosponsor: Forrest Mandeville (Republican), Senate

## Roll call votes

| Date | Chamber | Motion | Result | Yes | No | Other |
| --- | --- | --- | --- | --- | --- | --- |
| 2025-04-09 | Senate | Do Concur | pass | 49 | 0 |   |
| 2025-04-08 | Senate | Do Concur | pass | 49 | 0 |   |
| 2025-01-31 | House | Do Pass | pass | 99 | 0 |   |
| 2025-01-30 | House | Do Pass | pass | 100 | 0 |   |

## Actions (24)

- 2025-05-05: Chapter Number Assigned (House)
- 2025-05-01: Signed by Governor (House)
- 2025-04-22: Transmitted to Governor (House)
- 2025-04-22: Signed by President (Senate)
- 2025-04-18: Signed by Speaker (House)
- 2025-04-10: Returned from Enrolling (House)
- 2025-04-09: Sent to Enrolling (House)
- 2025-04-09: 3rd Reading (Senate)
- 2025-04-08: 2nd Reading (Senate)
- 2025-03-24: Committee Report (Senate)
- 2025-03-21: Committee Executive Action (Senate)
- 2025-03-05: Hearing (Senate)
- 2025-02-18: Referred to Committee (Senate)
- 2025-02-03: 1st Reading (Senate)
- 2025-01-31: Transmitted to Senate (House)
- 2025-01-31: 3rd Reading (House)
- 2025-01-30: 2nd Reading (House)
- 2025-01-24: Committee Report (House)
- 2025-01-23: Committee Executive Action (House)
- 2025-01-23: Committee Executive Action (House)
- 2025-01-14: Hearing (House)
- 2025-01-13: 1st Reading (House)
- 2025-01-13: Referred to Committee (House)
- 2025-01-13: Introduced (House)

## Bill text

- Enrolled, 2025-04-15: [PDF](https://docs.legmt.gov/download-ticket?ticketId=b22c6e80-e8de-4189-b2c0-eb004c5ad6c6)
- As Amended (Version 2), 2025-01-24: [PDF](https://docs.legmt.gov/download-ticket?ticketId=720c79ea-cce4-4b2c-ba2f-c1d2783fd53d)
- Introduced, 2025-01-13: [PDF](https://docs.legmt.gov/download-ticket?ticketId=fe9157c3-ebdb-491a-89b6-8f870e9d6ea5)

## Related bills

- SB 437: Revise definition of sex in Montana law (signed)
- HB 831: Increase elderly homeowner and renter income tax credit (vetoed)
- HB 628: Revise early literacy targeted intervention laws (vetoed)
- SB 410: Provide for Montana genomic security act (vetoed)
- SB 424: Revising the disabled veteran property tax assistance program (vetoed)
- SB 422: Generally revise laws relating to insurance coverage relating to cancer (vetoed)

## Sources
- [Enrolled (PDF)](https://docs.legmt.gov/download-ticket?ticketId=b22c6e80-e8de-4189-b2c0-eb004c5ad6c6)
- [As Amended (Version 2) (PDF)](https://docs.legmt.gov/download-ticket?ticketId=720c79ea-cce4-4b2c-ba2f-c1d2783fd53d)
- [Introduced (PDF)](https://docs.legmt.gov/download-ticket?ticketId=fe9157c3-ebdb-491a-89b6-8f870e9d6ea5)

## Related
- [SB 437: Revise definition of sex in Montana law](https://policyrisk.com/state-bill/MT-SB437-2025)
- [HB 831: Increase elderly homeowner and renter income tax credit](https://policyrisk.com/state-bill/MT-HB831-2025)
- [HB 628: Revise early literacy targeted intervention laws](https://policyrisk.com/state-bill/MT-HB628-2025)
- [SB 410: Provide for Montana genomic security act](https://policyrisk.com/state-bill/MT-SB410-2025)
- [SB 424: Revising the disabled veteran property tax assistance program](https://policyrisk.com/state-bill/MT-SB424-2025)
- [SB 422: Generally revise laws relating to insurance coverage relating to cancer](https://policyrisk.com/state-bill/MT-SB422-2025)
- [Montana bills](https://policyrisk.com/states/montana/bills)
- [Montana state hub](https://policyrisk.com/states/montana)
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Source: PRIA, https://policyrisk.com/state-bill/MT-HB180-2025 (as of 2026-10-19).