ORONOCO WWTP
NPDES ID: MN0071421
E — SNC: Effluent violation (monthly average limit)
The facility discharged more of a pollutant than its permit allows, based on a monthly average.
This quarter: 1 effluent violation.
Violations
May 31, 2026
Nitrogen, total [as N]
10% over limit
Discharged 11 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Numeric Violation
March 31, 2026
Nitrogen, total [as N]
125% over limit
Discharged 22.5 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Numeric Violation
February 28, 2026
Nitrogen, total [as N]
177% over limit
Discharged 27.7 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Numeric Violation
pH
0% over limit
Discharged 5.4 SU against a permitted limit of 6 SU (MO MIN)
DMR, Limited - Numeric Violation
January 31, 2026
Nitrogen, total [as N]
197% over limit
Discharged 29.7 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Numeric Violation
December 31, 2025
Nitrogen, total [as N]
53% over limit
Discharged 15.3 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Numeric Violation
First flagged
April 14, 2026 (5 months ago)
Last confirmed
September 15, 2026 (4 days ago)