CHARLESTON WWTF
NPDES ID: MO0120081
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
pH
0% over limit
Discharged 4.72 SU against a permitted limit of 6.5 SU (MINIMUM)
DMR, Limited - Numeric Violation
April 30, 2026
Nitrogen, ammonia total [as N]
31% over limit
Discharged 10.5 mg/L against a permitted limit of 8 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
pH
0% over limit
Discharged 5.98 SU against a permitted limit of 6.5 SU (MINIMUM)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
121% over limit
Discharged 3.53 mg/L against a permitted limit of 1.6 mg/L (MO AVG)
DMR, Limited - Numeric Violation
March 31, 2026
Nitrogen, ammonia total [as N]
318% over limit
Discharged 14.22 mg/L against a permitted limit of 3.4 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
46% over limit
Discharged 19.4 mg/L against a permitted limit of 13.3 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
February 28, 2026
Nitrogen, ammonia total [as N]
437% over limit
Discharged 18.25 mg/L against a permitted limit of 3.4 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
44% over limit
Discharged 19.2 mg/L against a permitted limit of 13.3 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
January 31, 2026
Nitrogen, ammonia total [as N]
187% over limit
Discharged 9.77 mg/L against a permitted limit of 3.4 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
7% over limit
Discharged 14.2 mg/L against a permitted limit of 13.3 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
April 30, 2025
BOD, 5-day, percent removal
163% over limit
Discharged 8 % against a permitted limit of 65 % (MO AV MN)
DMR, Limited - Numeric Violation
Solids, suspended percent removal
89% over limit
Discharged 34 % against a permitted limit of 65 % (MINIMUM)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
10% over limit
Discharged 1.76 mg/L against a permitted limit of 1.6 mg/L (MO AVG)
DMR, Limited - Numeric Violation
March 31, 2025
Nitrogen, ammonia total [as N]
166% over limit
Discharged 9.05 mg/L against a permitted limit of 3.4 mg/L (MO AVG)
DMR, Limited - Numeric Violation
February 28, 2025
Nitrogen, ammonia total [as N]
304% over limit
Discharged 13.75 mg/L against a permitted limit of 3.4 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, suspended percent removal
9% over limit
Discharged 62 % against a permitted limit of 65 % (MINIMUM)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
15% over limit
Discharged 15.3 mg/L against a permitted limit of 13.3 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
January 31, 2025
Nitrogen, ammonia total [as N]
154% over limit
Discharged 8.64 mg/L against a permitted limit of 3.4 mg/L (MO AVG)
DMR, Limited - Numeric Violation
First flagged
April 14, 2026 (3 months ago)
Last confirmed
August 1, 2026 (6 days ago)