Lewistown WWTP
Lewistown, MT · Fergus County · Publicly Owned Treatment Works
- Average flow
- 2.38 MGD
- Design flow
- 2.5 MGD
- NPDES permit
- MT0020044
- Administratively continued
- Permit expires
- August 2017
- Population served
- 7,675
- CWNS 2022
Lewistown WWTP is a publicly owned wastewater treatment works in Lewistown, Fergus County, Montana treating an average of 2.38 million gallons per day against a permitted design capacity of 2.5 MGD, serving about 7,675 residents. Treatment on site includes clarifiers, uncovered lagoons, carrousels / oxidation ditches, biogas silos. It discharges under NPDES permit MT0020044 (administratively continued), which expires in August 2017, with 32 recorded violations in the last three years.
Treatment technology
Treatment structures identified at this facility. Exact unit counts are available in Klarifi.
Clarifiers
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Uncovered lagoons
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Carrousels / oxidation ditches
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Biogas silos
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Compliance snapshot (last 3 years)
- Total violations
- 32
- Effluent violations
- 23
Based on NPDES Discharge Monitoring Reports. Full violation history, parameters and discharge data available in the Klarifi platform.
Key contacts
2 verified contacts for Lewistown WWTP, with validated emails and direct phone numbers.
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Names, validated emails and direct phone numbers for decision-makers at Lewistown WWTP, plus the full compliance history and discharge data.
Nearby wastewater treatment plants in Montana
Hobson · 21 mi away
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Denton · 29 mi away
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Harlowton · 48 mi away
0.07 MGD
Geraldine · 53 mi away
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Lavina · 59 mi away
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Belt · 73 mi away
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Highwood · 73 mi away
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Fort Benton · 77 mi away
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Lewistown WWTP: frequently asked questions
Sources and methodology
Flow, permit and violation figures come from the EPA's ICIS-NPDES discharge monitoring records. Population served comes from the Clean Watersheds Needs Survey 2022. Treatment structures are identified by Klarifi's review of aerial imagery, and capital improvement projects are extracted from published municipal budget documents. Violations are counted over the last three years of monitoring reports.
Data refreshed September 11, 2026; facility record last updated March 15, 2025.