BUTTERFIELD WWTF
NPDES ID: MO0126292
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: 6 effluent violations, 1 single-event violation, 4 permit schedule violations.
Violations
June 30, 2026
Nitrogen, ammonia total [as N]
368% over limit
Discharged 7.95 mg/L against a permitted limit of 1.7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
May 31, 2026
E. coli
Limit violation
Discharged 2420 MPN/100mL against a permitted limit of 126 MPN/100mL (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
124% over limit
Discharged 4.92 mg/L against a permitted limit of 2.2 mg/L (MO AVG)
DMR, Limited - Numeric Violation
April 30, 2026
E. coli
Limit violation
Discharged 2420 MPN/100mL against a permitted limit of 126 MPN/100mL (DAILY MX)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
20% over limit
Discharged 12 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
51% over limit
Discharged 4.09 mg/L against a permitted limit of 2.7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
March 31, 2026
Nitrogen, ammonia total [as N]
83% over limit
Discharged 5.67 mg/L against a permitted limit of 3.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
February 28, 2026
Nitrogen, ammonia total [as N]
348% over limit
Discharged 12.1 mg/L against a permitted limit of 2.7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
20% over limit
Discharged 12.1 mg/L against a permitted limit of 10.1 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
10% over limit
Discharged 11 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Numeric Violation
January 31, 2026
Nitrogen, ammonia total [as N]
220% over limit
Discharged 9.91 mg/L against a permitted limit of 3.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
pH
0% over limit
Discharged 9.91 SU against a permitted limit of 9 SU (MAXIMUM)
DMR, Limited - Numeric Violation
December 31, 2025
Toxicity [acute], Pimephales promelas [Fathead Minnow]
233% over limit
Discharged 1 toxic against a permitted limit of 0.3 toxic (DAILY MX)
DMR, Limited - Overdue
Toxicity [acute], Pimephales promelas [Fathead Minnow]
233% over limit
Discharged 1 toxic against a permitted limit of 0.3 toxic (DAILY MX)
DMR, Limited - Numeric Violation
Toxicity [acute], Ceriodaphnia dubia
233% over limit
Discharged 1 toxic against a permitted limit of 0.3 toxic (DAILY MX)
DMR, Limited - Overdue
Toxicity [acute], Ceriodaphnia dubia
233% over limit
Discharged 1 toxic against a permitted limit of 0.3 toxic (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
217% over limit
Discharged 9.83 mg/L against a permitted limit of 3.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
November 30, 2025
Nitrogen, ammonia total [as N]
180% over limit
Discharged 8.69 mg/L against a permitted limit of 3.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
October 31, 2025
E. coli
Limit violation
Discharged 2420 MPN/100mL against a permitted limit of 126 MPN/100mL (DAILY MX)
DMR, Limited - Numeric Violation
September 30, 2025
Nitrogen, ammonia total [as N]
85% over limit
Discharged 3.33 mg/L against a permitted limit of 1.8 mg/L (MO AVG)
DMR, Limited - Numeric Violation
August 31, 2025
Nitrogen, ammonia total [as N]
301% over limit
Discharged 5.21 mg/L against a permitted limit of 1.3 mg/L (MO AVG)
DMR, Limited - Numeric Violation
July 31, 2025
E. coli
Limit violation
Discharged 2420 MPN/100mL against a permitted limit of 126 MPN/100mL (DAILY MX)
DMR, Limited - Numeric Violation
pH
0% over limit
Discharged 6.48 SU against a permitted limit of 6.5 SU (MINIMUM)
DMR, Limited - Numeric Violation
May 31, 2025
E. coli
144% over limit
Discharged 308 MPN/100mL against a permitted limit of 126 MPN/100mL (DAILY MX)
DMR, Limited - Numeric Violation
April 30, 2025
pH
0% over limit
Discharged 6.42 SU against a permitted limit of 6.5 SU (MINIMUM)
DMR, Limited - Numeric Violation
March 31, 2025
E. coli
Limit violation
Discharged 242 MPN/100mL against a permitted limit of 126 MPN/100mL (DAILY MX)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
13% over limit
Discharged 17 mg/L against a permitted limit of 15 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
70% over limit
Discharged 17 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Numeric Violation
February 28, 2025
Nitrogen, ammonia total [as N]
304% over limit
Discharged 40.8 mg/L against a permitted limit of 10.1 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
E. coli
Limit violation
Discharged 2420 MPN/100mL against a permitted limit of 126 MPN/100mL (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
1411% over limit
Discharged 40.8 mg/L against a permitted limit of 2.7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
60% over limit
Discharged 24 mg/L against a permitted limit of 15 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
140% over limit
Discharged 24 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Numeric Violation
pH
0% over limit
Discharged 6.45 SU against a permitted limit of 6.5 SU (MINIMUM)
DMR, Limited - Numeric Violation
January 31, 2025
Nitrogen, ammonia total [as N]
76% over limit
Discharged 21.3 mg/L against a permitted limit of 12.1 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
587% over limit
Discharged 21.3 mg/L against a permitted limit of 3.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
December 31, 2024
E. coli
317% over limit
Discharged 525 MPN/100mL against a permitted limit of 126 MPN/100mL (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
142% over limit
Discharged 7.51 mg/L against a permitted limit of 3.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
First flagged
April 14, 2026 (3 months ago)
Last confirmed
August 1, 2026 (4 days ago)