WEST PORTSMOUTH WWTP
NPDES ID: OH0076309
S — SNC: Compliance schedule violation
The facility missed a deadline in its compliance schedule by more than 90 days.
This quarter: 7 effluent violations.
Violations
May 31, 2026
Nitrogen, ammonia total [as N]
21% over limit
Discharged 6.2 kg/d against a permitted limit of 5.11 kg/d (WKLY MAX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
260% over limit
Discharged 7.2 mg/L against a permitted limit of 2 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
15% over limit
Discharged 5.1 mg/L against a permitted limit of 6 mg/L (DAILY MN)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
233% over limit
Discharged 10 mg/L against a permitted limit of 3 mg/L (WKLY MAX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
26% over limit
Discharged 4.3 kg/d against a permitted limit of 3.41 kg/d (MO AVG)
DMR, Limited - Numeric Violation
April 30, 2026
Nitrogen, ammonia total [as N]
144% over limit
Discharged 6.1 mg/L against a permitted limit of 2.5 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
80% over limit
Discharged 8.1 mg/L against a permitted limit of 4.5 mg/L (WKLY MAX)
DMR, Limited - Numeric Violation
January 31, 2026
Copper, total recoverable
73% over limit
Discharged 0.019 mg/L against a permitted limit of 0.011 mg/L (MO AVG)
DMR, Limited - Numeric Violation
December 31, 2025
Nitrogen, ammonia total [as N]
29% over limit
Discharged 5.8 mg/L against a permitted limit of 4.5 mg/L (WKLY MAX)
DMR, Limited - Numeric Violation
October 31, 2025
Nitrogen, ammonia total [as N]
174% over limit
Discharged 14 kg/d against a permitted limit of 5.11 kg/d (WKLY MAX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
240% over limit
Discharged 6.8 mg/L against a permitted limit of 2 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
149% over limit
Discharged 8.5 kg/d against a permitted limit of 3.41 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
233% over limit
Discharged 10 mg/L against a permitted limit of 3 mg/L (WKLY MAX)
DMR, Limited - Numeric Violation
September 30, 2025
Nitrogen, ammonia total [as N]
272% over limit
Discharged 19 kg/d against a permitted limit of 5.11 kg/d (WKLY MAX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
146% over limit
Discharged 8.4 kg/d against a permitted limit of 3.41 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
400% over limit
Discharged 10 mg/L against a permitted limit of 2 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
13% over limit
Discharged 5.2 mg/L against a permitted limit of 6 mg/L (DAILY MN)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
233% over limit
Discharged 10 mg/L against a permitted limit of 3 mg/L (WKLY MAX)
DMR, Limited - Numeric Violation
August 31, 2025
Nitrogen, ammonia total [as N]
400% over limit
Discharged 10 mg/L against a permitted limit of 2 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
2% over limit
Discharged 5.2 kg/d against a permitted limit of 5.11 kg/d (WKLY MAX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
233% over limit
Discharged 10 mg/L against a permitted limit of 3 mg/L (WKLY MAX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
50% over limit
Discharged 5.1 kg/d against a permitted limit of 3.41 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
25% over limit
Discharged 4.5 mg/L against a permitted limit of 6 mg/L (DAILY MN)
DMR, Limited - Numeric Violation
E. coli, MTEC-MF
76% over limit
Discharged 500 MPN/100mL against a permitted limit of 284 MPN/100mL (WK GEOMN)
DMR, Limited - Numeric Violation
July 31, 2025
Nitrogen, ammonia total [as N]
88% over limit
Discharged 6.4 kg/d against a permitted limit of 3.41 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
233% over limit
Discharged 10 mg/L against a permitted limit of 3 mg/L (WKLY MAX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
370% over limit
Discharged 9.4 mg/L against a permitted limit of 2 mg/L (MO AVG)
DMR, Limited - Numeric Violation
E. coli, MTEC-MF
76% over limit
Discharged 500 MPN/100mL against a permitted limit of 284 MPN/100mL (WK GEOMN)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
22% over limit
Discharged 4.7 mg/L against a permitted limit of 6 mg/L (DAILY MN)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
70% over limit
Discharged 8.7 kg/d against a permitted limit of 5.11 kg/d (WKLY MAX)
DMR, Limited - Numeric Violation
June 30, 2025
Oxygen, dissolved [DO]
2% over limit
Discharged 5.9 mg/L against a permitted limit of 6 mg/L (DAILY MN)
DMR, Limited - Numeric Violation
E. coli, MTEC-MF
178% over limit
Discharged 790 MPN/100mL against a permitted limit of 284 MPN/100mL (WK GEOMN)
DMR, Limited - Numeric Violation
May 31, 2025
Nitrogen, ammonia total [as N]
233% over limit
Discharged 10 mg/L against a permitted limit of 3 mg/L (WKLY MAX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
409% over limit
Discharged 26 kg/d against a permitted limit of 5.11 kg/d (WKLY MAX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
85% over limit
Discharged 3.7 mg/L against a permitted limit of 2 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
126% over limit
Discharged 7.7 kg/d against a permitted limit of 3.41 kg/d (MO AVG)
DMR, Limited - Numeric Violation
April 30, 2025
pH, maximum
0% over limit
Discharged 9.01 SU against a permitted limit of 9 SU (DAILY MX)
DMR, Limited - Numeric Violation
October 31, 2024
E. coli, MTEC-MF
23% over limit
Discharged 350 MPN/100mL against a permitted limit of 284 MPN/100mL (WK GEOMN)
DMR, Limited - Numeric Violation
September 30, 2024
E. coli, MTEC-MF
23% over limit
Discharged 350 MPN/100mL against a permitted limit of 284 MPN/100mL (WK GEOMN)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
137% over limit
Discharged 7.1 mg/L against a permitted limit of 3 mg/L (WKLY MAX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
25% over limit
Discharged 2.5 mg/L against a permitted limit of 2 mg/L (MO AVG)
DMR, Limited - Numeric Violation
July 31, 2024
E. coli, MTEC-MF
6% over limit
Discharged 300 MPN/100mL against a permitted limit of 284 MPN/100mL (WK GEOMN)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
233% over limit
Discharged 10 mg/L against a permitted limit of 3 mg/L (WKLY MAX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
70% over limit
Discharged 3.4 mg/L against a permitted limit of 2 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
23% over limit
Discharged 6.3 kg/d against a permitted limit of 5.11 kg/d (WKLY MAX)
DMR, Limited - Numeric Violation
First flagged
April 14, 2026 (3 months ago)
Last confirmed
July 13, 2026 (24 days ago)