West St Tammany Regional STP
Madisonville, LA · St. Tammany County · Publicly Owned Treatment Works
- Average flow
- 0.43 MGD
- Design flow
- 1.25 MGD
- NPDES permit
- LA0120235
- Effective
- Permit expires
- September 2029
- Population served
- 6,435
- CWNS 2022
West St Tammany Regional STP is a publicly owned wastewater treatment works in Madisonville, St. Tammany County, Louisiana treating an average of 0.43 million gallons per day against a permitted design capacity of 1.25 MGD, serving about 6,435 residents. It discharges under NPDES permit LA0120235 (effective), which expires in September 2029, with 10 recorded violations in the last three years.
Treatment technology
Treatment structures identified at this facility. Exact unit counts are available in Klarifi.
Treatment structure data not yet analyzed for this facility.
Compliance snapshot (last 3 years)
- Total violations
- 10
- Effluent violations
- 10
Based on NPDES Discharge Monitoring Reports. Full violation history, parameters and discharge data available in the Klarifi platform.
Key contacts
3 verified contacts for West St Tammany Regional STP, with validated emails and direct phone numbers.
Unlock 3 verified contacts
Names, validated emails and direct phone numbers for decision-makers at West St Tammany Regional STP, plus the full compliance history and discharge data.
Nearby wastewater treatment plants in Louisiana
Covington · 2 mi away
0.06 MGD
Ponchatoula · 3 mi away
0.23 MGD
Madisonville · 4 mi away
0.06 MGD
Madisonville · 5 mi away
0.2 MGD
Covington · 6 mi away
0.13 MGD
Covington · 7 mi away
0.12 MGD
Mandeville · 8 mi away
0.37 MGD
Mandeville · 8 mi away
0.3 MGD
West St Tammany Regional 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 September 11, 2026; facility record last updated July 7, 2026.