Manhattan WWTF
Manhattan, MT · Gallatin County · Publicly Owned Treatment Works
- Average flow
- 0.32 MGD
- Design flow
- 0.37 MGD
- NPDES permit
- MT0021857
- Administratively continued
- Permit expires
- August 2015
- Population served
- 3,366
- CWNS 2022
Manhattan WWTF is a publicly owned wastewater treatment works in Manhattan, Gallatin County, Montana treating an average of 0.32 million gallons per day against a permitted design capacity of 0.37 MGD, serving about 3,366 residents. Treatment on site includes biological n removal. It discharges under NPDES permit MT0021857 (administratively continued), which expires in August 2015, with 20 recorded violations in the last three years.
Treatment technology
Treatment structures identified at this facility. Exact unit counts are available in Klarifi.
Biological N removal
unit processUnlock exact unit counts →
Compliance snapshot (last 3 years)
- Total violations
- 20
- Effluent violations
- 16
Based on NPDES Discharge Monitoring Reports. Full violation history, parameters and discharge data available in the Klarifi platform.
Key contacts
Decision-makers at Manhattan WWTF.
No verified contacts on file yet
Klarifi verifies plant and municipal decision-makers continuously. Start a free trial to browse contacts at nearby plants and flag this one for verification.
Nearby wastewater treatment plants in Montana
Belgrade · 9 mi away
0.15 MGD
Three Forks · 10 mi away
0.31 MGD
Belgrade · 10 mi away
0.5 MGD
Willow Creek · 16 mi away
—
Bozeman · 17 mi away
7.35 MGD
Bozeman · 19 mi away
0.19 MGD
Bozeman · 24 mi away
0.13 MGD
Townsend · 33 mi away
0.19 MGD
Manhattan WWTF: 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 November 13, 2025.