Friday Harbor STP
375 Tucker Ave, Friday Harbor, WA 98250 · San Juan County · Publicly Owned Treatment Works
- Average flow
- 0.4 MGD
- Design flow
- —
- NPDES permit
- WAG994576
- Terminated
- Permit expires
- December 2026
- Population served
- 2,495
- CWNS 2022
Friday Harbor STP is a publicly owned wastewater treatment works in Friday Harbor, San Juan County, Washington treating an average of 0.4 million gallons per day, serving about 2,495 residents. It discharges under NPDES permit WAG994576 (terminated), which expires in December 2026, with 33 recorded violations in the last three years.
Treatment technology
Treatment structures and unit processes at Friday Harbor STP.
Treatment structure data not yet analyzed for this facility.
Compliance snapshot (last 3 years)
- Total violations
- 33
- Effluent violations
- 30
Based on NPDES Discharge Monitoring Reports. Full violation history, parameters and discharge data available in the Klarifi platform.
Key contacts
2 verified contacts for Friday Harbor STP, with validated emails and direct phone numbers.
Unlock 2 verified contacts
Names, validated emails and direct phone numbers for decision-makers at Friday Harbor STP, plus the full compliance history and discharge data.
Nearby wastewater treatment plants in Washington
Lopez Island · 5 mi away
0.02 MGD
Orcas · 6 mi away
0.0063 MGD
Bellingham · 26 mi away
0.18 MGD
Bellingham · 26 mi away
15.62 MGD
Mount Vernon · 27 mi away
0.28 MGD
Bellingham · 27 mi away
0.0032 MGD
Blaine · 28 mi away
1.17 MGD
Ferndale · 28 mi away
2.26 MGD
Friday Harbor STP: 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 September 11, 2026.
Wastewater terms: POTW · MGD · NPDES permit · Inflow and infiltration · Biological nutrient removal · Tertiary treatment · all terms