Clatskanie WWTP
190 NW 4th St, Clatskanie, OR 97016 · Columbia County · Publicly Owned Treatment Works
- Average flow
- 0.29 MGD
- Design flow
- 0.5 MGD
- NPDES permit
- OR0020231
- Administratively continued
- Permit expires
- June 2017
- Population served
- 1,780
- CWNS 2022
Clatskanie WWTP is a publicly owned wastewater treatment works in Clatskanie, Columbia County, Oregon treating an average of 0.29 million gallons per day against a permitted design capacity of 0.5 MGD, serving about 1,780 residents. It discharges under NPDES permit OR0020231 (administratively continued), which expires in June 2017, with 9 recorded violations in the last three years.
Treatment technology
One treatment structure or unit process identified at Clatskanie WWTP.
Available with a free Klarifi account
See the full treatment train at Clatskanie WWTP: structures, unit processes and planned upgrades, with exact unit counts.
Compliance snapshot (last 3 years)
- Total violations
- 9
- Effluent violations
- 9
Based on NPDES Discharge Monitoring Reports. Full violation history, parameters and discharge data available in the Klarifi platform.
Key contacts
Decision-makers at Clatskanie 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
Clatskanie · 8 mi away
0.04 MGD
Rainier · 13 mi away
0.39 MGD
Vernonia · 17 mi away
0.39 MGD
Astoria · 28 mi away
4.38 MGD
Scappoose · 30 mi away
1.02 MGD
Warrenton · 34 mi away
—
Seaside · 35 mi away
1.65 MGD
Cannon Beach · 39 mi away
0.59 MGD
Clatskanie 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 November 27, 2025.
Wastewater terms: POTW · MGD · NPDES permit · Inflow and infiltration · Sludge dewatering · Biological nutrient removal · all terms