St Clair WWTP
300 Cedar Street, St Clair, MI 48079 · Saint Clair County · Publicly Owned Treatment Works
- Average flow
- 0.99 MGD
- Design flow
- —
- NPDES permit
- MI0020591
- Administratively continued
- Permit expires
- October 2026
- Population served
- 5,913
- CWNS 2022
St Clair WWTP is a publicly owned wastewater treatment works in St Clair, Saint Clair County, Michigan treating an average of 0.99 million gallons per day, serving about 5,913 residents. It discharges under NPDES permit MI0020591 (administratively continued), which expires in October 2026, with 0 recorded violations in the last three years.
Treatment technology
2 treatment structures and unit processes identified at St Clair WWTP.
Available with a free Klarifi account
See the full treatment train at St Clair WWTP: structures, unit processes and planned upgrades, with exact unit counts.
Compliance snapshot (last 3 years)
- Total violations
- 0
- Effluent violations
- 0
Based on NPDES Discharge Monitoring Reports. Full violation history, parameters and discharge data available in the Klarifi platform.
Key contacts
6 verified contacts for St Clair WWTP, with validated emails and direct phone numbers.
Unlock 6 verified contacts (3 more than shown)
Names, validated emails and direct phone numbers for decision-makers at St Clair WWTP, plus the full compliance history and discharge data.
Nearby wastewater treatment plants in Michigan
East China · 4 mi away
0.45 MGD
Marysville · 6 mi away
2.04 MGD
Marine City · 8 mi away
1.11 MGD
Port Huron · 11 mi away
7.93 MGD
Algonac · 14 mi away
1.66 MGD
Memphis · 15 mi away
—
New Baltimore · 16 mi away
1.05 MGD
Emmett · 18 mi away
0.68 MGD
St Clair 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 April 4, 2025.
Wastewater terms: POTW · MGD · NPDES permit · Inflow and infiltration · Oxidation ditch · Anaerobic digester · all terms