Philomath WWTP
Corvallis, OR · Benton County · Publicly Owned Treatment Works
- Average flow
- 0.43 MGD
- Design flow
- 0.83 MGD
- NPDES permit
- OR0032441
- Administratively continued
- Permit expires
- June 2017
- Population served
- 5,431
- CWNS 2022
Philomath WWTP is a publicly owned wastewater treatment works in Corvallis, Benton County, Oregon treating an average of 0.43 million gallons per day against a permitted design capacity of 0.83 MGD, serving about 5,431 residents. Treatment on site includes uncovered lagoons. It discharges under NPDES permit OR0032441 (administratively continued), which expires in June 2017, with 11 recorded violations in the last three years.
Treatment technology
Treatment structures identified at this facility. Exact unit counts are available in Klarifi.
Uncovered lagoons
Unlock
Unlock exact unit counts →
Compliance snapshot (last 3 years)
- Total violations
- 11
- Effluent violations
- 0
Based on NPDES Discharge Monitoring Reports. Full violation history, parameters and discharge data available in the Klarifi platform.
Key contacts
Decision-makers at Philomath WWTP.
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 Oregon
Tangent · 10 mi away
0.09 MGD
Corvallis · 13 mi away
0.1 MGD
Monroe · 13 mi away
0.0027 MGD
Halsey · 14 mi away
0.04 MGD
Monroe · 15 mi away
0.04 MGD
Albany · 16 mi away
4.59 MGD
Harrisburg · 18 mi away
—
Brownsville · 19 mi away
0.1 MGD
Philomath 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 October 1, 2025.