Lewistown WWTP
620 Metis Avenue, Lewistown, MT 59457 · Fergus County · Publicly Owned Treatment Works
- Average flow
- 1.82 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 1.82 million gallons per day against a permitted design capacity of 2.5 MGD, serving about 7,675 residents. It discharges under NPDES permit MT0020044 (administratively continued), which expires in August 2017, with 32 recorded violations in the last three years.
Treatment technology
4 treatment structures and unit processes identified at Lewistown WWTP.
Available with a free Klarifi account
See the full treatment train at Lewistown WWTP: structures, unit processes and planned upgrades, with exact unit counts.
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.
EPA enforcement history
Federal civil enforcement cases, compliance inspections and informal actions recorded for Lewistown WWTP in EPA's ICIS system.
- Formal actions
- 0
- none on record
- EPA inspections
- 1
- latest Jun 2004
No formal federal enforcement case is on record for this plant.
Full case history with a free Klarifi account
Every action against Lewistown WWTP with dates, milestones, violation types and EPA's complete case summaries, plus inspections and informal actions.
Key contacts
2 verified contacts for Lewistown WWTP, with validated emails and direct phone numbers.
Unlock 2 verified contacts
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
—
Denton · 29 mi away
—
Winifred · 34 mi away
—
Harlowton · 48 mi away
0.08 MGD
Winnett · 52 mi away
0.07 MGD
Geraldine · 53 mi away
—
Lavina · 59 mi away
18.51 MGD
Belt · 73 mi away
0.82 MGD
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 October 26, 2026; facility record last updated March 15, 2025.
Wastewater terms: POTW · MGD · NPDES permit · Inflow and infiltration · Biosolids · Filter press · all terms