MARQUAND WWTP
NPDES ID: MO0116246
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: 8 effluent violations.
Violations
May 31, 2026
BOD, 5-day, percent removal
7% over limit
Discharged 84 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
Solids, suspended percent removal
13% over limit
Discharged 83 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
741% over limit
Discharged 18.5 mg/L against a permitted limit of 2.2 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
53% over limit
Discharged 18.5 mg/L against a permitted limit of 12.1 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
E. coli
90% over limit
Discharged 1200 MPN/100mL against a permitted limit of 630 MPN/100mL (7 DA GEO)
DMR, Limited - Numeric Violation
E. coli
852% over limit
Discharged 1200 MPN/100mL against a permitted limit of 126 MPN/100mL (30DA GM)
DMR, Limited - Numeric Violation
April 30, 2026
Nitrogen, ammonia total [as N]
10% over limit
Discharged 13.3 mg/L against a permitted limit of 12.1 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
393% over limit
Discharged 13.3 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]
28% over limit
Discharged 3.96 mg/L against a permitted limit of 3.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, percent removal
173% over limit
Discharged 59 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
February 28, 2026
Nitrogen, ammonia total [as N]
459% over limit
Discharged 15.1 mg/L against a permitted limit of 2.7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
50% over limit
Discharged 15.1 mg/L against a permitted limit of 10.1 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Solids, suspended percent removal
73% over limit
Discharged 74 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
January 31, 2026
Nitrogen, ammonia total [as N]
500% over limit
Discharged 18.6 mg/L against a permitted limit of 3.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
54% over limit
Discharged 18.6 mg/L against a permitted limit of 12.1 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
December 31, 2025
BOD, 5-day, percent removal
567% over limit
Discharged 0 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
Solids, suspended percent removal
40% over limit
Discharged 79 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
229% over limit
Discharged 10.2 mg/L against a permitted limit of 3.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
November 30, 2025
BOD, 5-day, percent removal
493% over limit
Discharged 11 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
159% over limit
Discharged 8.03 mg/L against a permitted limit of 3.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, suspended percent removal
567% over limit
Discharged 0 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
October 31, 2025
Solids, suspended percent removal
53% over limit
Discharged 77 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
September 30, 2025
Nitrogen, ammonia total [as N]
415% over limit
Discharged 9.27 mg/L against a permitted limit of 1.8 mg/L (MO AVG)
DMR, Limited - Numeric Violation
August 31, 2025
BOD, 5-day, percent removal
13% over limit
Discharged 83 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
July 31, 2025
BOD, 5-day, percent removal
567% over limit
Discharged 0 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
48% over limit
Discharged 66.4 mg/L against a permitted limit of 45 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
121% over limit
Discharged 66.4 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
700% over limit
Discharged 12 mg/L against a permitted limit of 1.5 mg/L (MO AVG)
DMR, Limited - Numeric Violation
June 30, 2025
BOD, 5-day, percent removal
47% over limit
Discharged 78 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
E. coli
284% over limit
Discharged 2420 MPN/100mL against a permitted limit of 630 MPN/100mL (7 DA GEO)
DMR, Limited - Numeric Violation
E. coli
1821% over limit
Discharged 2420 MPN/100mL against a permitted limit of 126 MPN/100mL (30DA GM)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
47% over limit
Discharged 17.8 mg/L against a permitted limit of 12.1 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
947% over limit
Discharged 17.8 mg/L against a permitted limit of 1.7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
May 31, 2025
Solids, suspended percent removal
233% over limit
Discharged 50 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
E. coli
284% over limit
Discharged 2420 MPN/100mL against a permitted limit of 630 MPN/100mL (7 DA GEO)
DMR, Limited - Numeric Violation
E. coli
1821% over limit
Discharged 2420 MPN/100mL against a permitted limit of 126 MPN/100mL (30DA GM)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
56% over limit
Discharged 18.9 mg/L against a permitted limit of 12.1 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
759% over limit
Discharged 18.9 mg/L against a permitted limit of 2.2 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, percent removal
567% over limit
Discharged 0 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
April 30, 2025
E. coli
1821% over limit
Discharged 2420 MPN/100mL against a permitted limit of 126 MPN/100mL (30DA GM)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
208% over limit
Discharged 8.32 mg/L against a permitted limit of 2.7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
E. coli
284% over limit
Discharged 2420 MPN/100mL against a permitted limit of 630 MPN/100mL (7 DA GEO)
DMR, Limited - Numeric Violation
March 31, 2025
Solids, suspended percent removal
567% over limit
Discharged 0 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
BOD, 5-day, percent removal
160% over limit
Discharged 61 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
February 28, 2025
Nitrogen, ammonia total [as N]
141% over limit
Discharged 6.52 mg/L against a permitted limit of 2.7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, percent removal
567% over limit
Discharged 0 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
Solids, suspended percent removal
193% over limit
Discharged 56 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
January 31, 2025
Solids, suspended percent removal
567% over limit
Discharged 0 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
193% over limit
Discharged 9.09 mg/L against a permitted limit of 3.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, percent removal
567% over limit
Discharged 0 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
December 31, 2024
Nitrogen, ammonia total [as N]
390% over limit
Discharged 15.2 mg/L against a permitted limit of 3.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, suspended percent removal
107% over limit
Discharged 69 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
BOD, 5-day, percent removal
567% over limit
Discharged 0 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
26% over limit
Discharged 15.2 mg/L against a permitted limit of 12.1 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
November 30, 2024
Nitrogen, ammonia total [as N]
171% over limit
Discharged 8.4 mg/L against a permitted limit of 3.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, percent removal
113% over limit
Discharged 68 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
October 31, 2024
Nitrogen, ammonia total [as N]
416% over limit
Discharged 12.9 mg/L against a permitted limit of 2.5 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
7% over limit
Discharged 12.9 mg/L against a permitted limit of 12.1 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
September 30, 2024
BOD, 5-day, percent removal
347% over limit
Discharged 33 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
1044% over limit
Discharged 20.6 mg/L against a permitted limit of 1.8 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
70% over limit
Discharged 20.6 mg/L against a permitted limit of 12.1 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
21% over limit
Discharged 36.2 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
August 31, 2024
BOD, 5-day, percent removal
347% over limit
Discharged 33 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
104% over limit
Discharged 20.6 mg/L against a permitted limit of 10.1 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
1485% over limit
Discharged 20.6 mg/L against a permitted limit of 1.3 mg/L (MO AVG)
DMR, Limited - Numeric Violation
July 31, 2024
Nitrogen, ammonia total [as N]
1053% over limit
Discharged 17.3 mg/L against a permitted limit of 1.5 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
43% over limit
Discharged 17.3 mg/L against a permitted limit of 12.1 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
First flagged
April 14, 2026 (3 months ago)
Last confirmed
July 13, 2026 (23 days ago)