MAWC SHAMROCK HEIGHTS SUBDIVISION WWTP
NPDES ID: MO0097632
E — SNC: Effluent violation (monthly average limit)
The facility discharged more of a pollutant than its permit allows, based on a monthly average.
Violations
March 31, 2026
Nitrogen, ammonia total [as N]
881% over limit
Discharged 30.4 mg/L against a permitted limit of 3.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
151% over limit
Discharged 30.4 mg/L against a permitted limit of 12.1 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
December 31, 2025
Nitrogen, ammonia total [as N]
795% over limit
Discharged 19.7 mg/L against a permitted limit of 2.2 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
143% over limit
Discharged 20.4 mg/L against a permitted limit of 8.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
September 30, 2025
Nitrogen, ammonia total [as N]
13% over limit
Discharged 9.52 mg/L against a permitted limit of 8.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
852% over limit
Discharged 9.52 mg/L against a permitted limit of 1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
June 30, 2025
Nitrogen, ammonia total [as N]
267% over limit
Discharged 5.51 mg/L against a permitted limit of 1.5 mg/L (MO AVG)
DMR, Limited - Numeric Violation
pH
0% over limit
Discharged 9.47 SU against a permitted limit of 9 SU (MAXIMUM)
DMR, Limited - Numeric Violation
December 31, 2024
Nitrogen, ammonia total [as N]
418% over limit
Discharged 11.4 mg/L against a permitted limit of 2.2 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
38% over limit
Discharged 11.6 mg/L against a permitted limit of 8.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
First flagged
April 14, 2026 (3 months ago)
Last confirmed
July 13, 2026 (23 days ago)