EAST HELENA WWTF
NPDES ID: MT0022560
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: 5 effluent violations.
Violations
May 31, 2026
BOD, 5-day, 20 deg. C
23% over limit
Discharged 36.92 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
April 30, 2026
Copper, total recoverable
37% over limit
Discharged 0.016 mg/L against a permitted limit of 0.0117 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
70% over limit
Discharged 50.93 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, total [as N]
33% over limit
Discharged 32.13411973 kg/d against a permitted limit of 24.1981998 kg/d (MO AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
47% over limit
Discharged 66.33 mg/L against a permitted limit of 45 mg/L (WKLY MAX)
DMR, Limited - Numeric Violation
March 31, 2026
Nitrogen, total [as N]
33% over limit
Discharged 32.21129973 kg/d against a permitted limit of 24.1981998 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Copper, total recoverable
45% over limit
Discharged 0.017 mg/L against a permitted limit of 0.0117 mg/L (MO AVG)
DMR, Limited - Numeric Violation
February 28, 2026
Nitrogen, total [as N]
27% over limit
Discharged 30.64045974 kg/d against a permitted limit of 24.1981998 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Copper, total recoverable
62% over limit
Discharged 0.019 mg/L against a permitted limit of 0.0117 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Copper, total recoverable
9% over limit
Discharged 0.019 mg/L against a permitted limit of 0.0175 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
January 31, 2026
Nitrogen, total [as N]
29% over limit
Discharged 31.30329974 kg/d against a permitted limit of 24.1981998 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Phosphorus, total [as P]
2% over limit
Discharged 5.20737996 kg/d against a permitted limit of 5.08479996 kg/d (MO AVG)
DMR, Limited - Numeric Violation
October 31, 2025
E. coli, MTEC-MF
543% over limit
Discharged 1620.59 MPN/100mL against a permitted limit of 252 MPN/100mL (MX 7D GM)
DMR, Limited - Numeric Violation
September 30, 2025
Phosphorus, total [as P]
171% over limit
Discharged 6.75551994 kg/d against a permitted limit of 2.49699998 kg/d (MO AVG)
DMR, Limited - Numeric Violation
August 31, 2025
Phosphorus, total [as P]
230% over limit
Discharged 8.24917993 kg/d against a permitted limit of 2.49699998 kg/d (MO AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
3% over limit
Discharged 31 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
July 31, 2025
Nitrogen, total [as N]
102% over limit
Discharged 48.87763959 kg/d against a permitted limit of 24.1981998 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Phosphorus, total [as P]
499% over limit
Discharged 14.95021987 kg/d against a permitted limit of 2.49699998 kg/d (MO AVG)
DMR, Limited - Numeric Violation
E. coli, MTEC-MF
822% over limit
Discharged 1161.44 MPN/100mL against a permitted limit of 126 MPN/100mL (MOAV GEO)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
13% over limit
Discharged 33.93 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
13% over limit
Discharged 51 mg/L against a permitted limit of 45 mg/L (WKLY MAX)
DMR, Limited - Numeric Violation
E. coli, MTEC-MF
1054% over limit
Discharged 2908.13 MPN/100mL against a permitted limit of 252 MPN/100mL (MX 7D GM)
DMR, Limited - Numeric Violation
June 30, 2025
E. coli, MTEC-MF
58% over limit
Discharged 199.03 MPN/100mL against a permitted limit of 126 MPN/100mL (MOAV GEO)
DMR, Limited - Numeric Violation
E. coli, MTEC-MF
860% over limit
Discharged 2419.6 MPN/100mL against a permitted limit of 252 MPN/100mL (MX 7D GM)
DMR, Limited - Numeric Violation
Phosphorus, total [as P]
95% over limit
Discharged 9.91989992 kg/d against a permitted limit of 5.08479996 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, total [as N]
67% over limit
Discharged 40.41961966 kg/d against a permitted limit of 24.1981998 kg/d (MO AVG)
DMR, Limited - Numeric Violation
May 31, 2025
Nitrogen, total [as N]
8% over limit
Discharged 26.05505978 kg/d against a permitted limit of 24.1981998 kg/d (MO AVG)
DMR, Limited - Numeric Violation
March 31, 2025
Copper, total recoverable
3% over limit
Discharged 0.018 mg/L against a permitted limit of 0.0175 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Copper, total recoverable
54% over limit
Discharged 0.018 mg/L against a permitted limit of 0.0117 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, total [as N]
48% over limit
Discharged 35.7161797 kg/d against a permitted limit of 24.1981998 kg/d (MO AVG)
DMR, Limited - Numeric Violation
February 28, 2025
Copper, total recoverable
20% over limit
Discharged 0.014 mg/L against a permitted limit of 0.0117 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Phosphorus, total [as P]
17% over limit
Discharged 5.94285995 kg/d against a permitted limit of 5.08479996 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, total [as N]
62% over limit
Discharged 39.32093967 kg/d against a permitted limit of 24.1981998 kg/d (MO AVG)
DMR, Limited - Numeric Violation
July 31, 2024
Phosphorus, total [as P]
11% over limit
Discharged 2.76939998 kg/d against a permitted limit of 2.49699998 kg/d (MO AVG)
DMR, Limited - Numeric Violation
First flagged
April 14, 2026 (3 months ago)
Last confirmed
July 13, 2026 (23 days ago)