GARRETT WWTP
NPDES ID: IN0022969
X — SNC: Effluent violation (non-monthly average limit)
The facility discharged more of a pollutant than its permit allows, measured over a period other than a monthly average.
This quarter: 8 effluent violations, 4 reporting violations.
Violations
April 30, 2026
Toxicity [acute], Pimephales promelas [Fathead Minnow]
0% over limit
Discharged 0 toxic against a permitted limit of 1 toxic (MAXIMUM)
DMR, Limited - Overdue
Toxicity [acute], Ceriodaphnia dubia
0% over limit
Discharged 0 toxic against a permitted limit of 1 toxic (MAXIMUM)
DMR, Limited - Overdue
Toxicity [chronic], Pimephales promelas [Fathead Minnow]
0% over limit
Discharged 0 toxic against a permitted limit of 1 toxic (MAXIMUM)
DMR, Limited - Overdue
Toxicity [chronic], Ceriodaphnia dubia
0% over limit
Discharged 0 toxic against a permitted limit of 1 toxic (MAXIMUM)
DMR, Limited - Overdue
Mercury, total recoverable
67% over limit
Discharged 0.00000318 mg/L against a permitted limit of 0.0000019 mg/L (ROLL AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
27% over limit
Discharged 86.62319927 kg/d against a permitted limit of 68.09999943 kg/d (MX WK AV)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
37% over limit
Discharged 22.36403981 kg/d against a permitted limit of 16.34399986 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Solids, total suspended
26% over limit
Discharged 68.46319942 kg/d against a permitted limit of 54.47999954 kg/d (MO AVG)
DMR, Limited - Numeric Violation
E. coli, colony forming units [CFU]
330% over limit
Discharged 1011 MPN/100mL against a permitted limit of 235 MPN/100mL (DAILY MX)
DMR, Limited - Numeric Violation
Solids, total suspended
132% over limit
Discharged 189.68119841 kg/d against a permitted limit of 81.71999931 kg/d (MX WK AV)
DMR, Limited - Numeric Violation
March 31, 2026
Nitrogen, ammonia total [as N]
28% over limit
Discharged 20.90215982 kg/d against a permitted limit of 16.34399986 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
February 28, 2026
Mercury, total recoverable
67% over limit
Discharged 0.00000318 mg/L against a permitted limit of 0.0000019 mg/L (ROLL AVG)
DMR, Limited - Numeric Violation
December 31, 2025
Mercury, total recoverable
131% over limit
Discharged 0.00000438 mg/L against a permitted limit of 0.0000019 mg/L (ROLL AVG)
DMR, Limited - Numeric Violation
October 31, 2025
Mercury, total recoverable
174% over limit
Discharged 0.00000521 mg/L against a permitted limit of 0.0000019 mg/L (ROLL AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
2% over limit
Discharged 15.69023987 kg/d against a permitted limit of 15.43599987 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
77% over limit
Discharged 6.01 mg/L against a permitted limit of 3.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
August 31, 2025
Mercury, total recoverable
205% over limit
Discharged 0.00000579 mg/L against a permitted limit of 0.0000019 mg/L (ROLL AVG)
DMR, Limited - Numeric Violation
July 31, 2025
Solids, total suspended
0% over limit
Discharged 4.6 mg/L against a permitted limit of 12 mg/L (MO AVG)
DMR, Limited - Overdue
Solids, total suspended
0% over limit
Discharged 9.5 mg/L against a permitted limit of 18 mg/L (MX WK AV)
DMR, Limited - Overdue
Solids, total suspended
0% over limit
Discharged 21.33799982 kg/d against a permitted limit of 81.71999931 kg/d (MX WK AV)
DMR, Limited - Overdue
Solids, total suspended
0% over limit
Discharged 10.70985991 kg/d against a permitted limit of 54.47999954 kg/d (MO AVG)
DMR, Limited - Overdue
June 30, 2025
Mercury, total recoverable
243% over limit
Discharged 0.00000652 mg/L against a permitted limit of 0.0000019 mg/L (ROLL AVG)
DMR, Limited - Numeric Violation
May 31, 2025
BOD, carbonaceous [5 day, 20 C]
0% over limit
Discharged 16.98413986 kg/d against a permitted limit of 68.09999943 kg/d (MX WK AV)
DMR, Limited - Overdue
Phosphorus, total [as P]
0% over limit
Discharged 0.412 mg/L against a permitted limit of 1 mg/L (MO AVG)
DMR, Limited - Overdue
Nitrogen, ammonia total [as N]
13% over limit
Discharged 3.844 mg/L against a permitted limit of 3.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
April 30, 2025
Phosphorus, total percent removal
0% over limit
Discharged 90.3 % against a permitted limit of 80 % (MO AV MN)
DMR, Limited - Overdue
Nitrogen, ammonia total [as N]
213% over limit
Discharged 11.27 mg/L against a permitted limit of 3.6 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Phosphorus, total [as P]
0% over limit
Discharged 1.64711199 kg/d against a permitted limit of 0 kg/d (MO AVG)
DMR, Monitor Only - Overdue
BOD, carbonaceous [5 day, 20 C]
0% over limit
Discharged 30.59051974 kg/d against a permitted limit of 68.09999943 kg/d (MX WK AV)
DMR, Limited - Overdue
Solids, total suspended
0% over limit
Discharged 75.95419936 kg/d against a permitted limit of 81.71999931 kg/d (MX WK AV)
DMR, Limited - Overdue
BOD, carbonaceous [5 day, 20 C]
0% over limit
Discharged 18.79559984 kg/d against a permitted limit of 45.39999962 kg/d (MO AVG)
DMR, Limited - Overdue
Flow, total
0% over limit
Discharged 1.22111647 MGD against a permitted limit of 0 MGD (MO TOTAL)
DMR, Monitor Only - Overdue
Solids, total suspended
0% over limit
Discharged 29.89589975 kg/d against a permitted limit of 54.47999954 kg/d (MO AVG)
DMR, Limited - Overdue
BOD, carbonaceous [5 day, 20 C]
0% over limit
Discharged 5.46 mg/L against a permitted limit of 15 mg/L (MX WK AV)
DMR, Limited - Overdue
Nitrogen, ammonia total [as N]
0% over limit
Discharged 2.68450198 kg/d against a permitted limit of 7.26399994 kg/d (MO AVG)
DMR, Limited - Overdue
Nitrogen, ammonia total [as N]
33% over limit
Discharged 21.77383982 kg/d against a permitted limit of 16.34399986 kg/d (DAILY MX)
DMR, Limited - Overdue
Nitrogen, ammonia total [as N]
33% over limit
Discharged 21.77383982 kg/d against a permitted limit of 16.34399986 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Mercury, total recoverable
302% over limit
Discharged 0.00000763 mg/L against a permitted limit of 0.0000019 mg/L (ROLL AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
0% over limit
Discharged 4.9 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Overdue
Flow, in conduit or thru treatment plant
0% over limit
Discharged 1.2372 MGD against a permitted limit of 0 MGD (MO AVG)
DMR, Monitor Only - Overdue
Nitrogen, total [as N]
0% over limit
Discharged 237.18017621 kg/d against a permitted limit of 0 kg/d (MO AVG)
DMR, Monitor Only - Overdue
February 28, 2025
Mercury, total recoverable
307% over limit
Discharged 0.00000773 mg/L against a permitted limit of 0.0000019 mg/L (ROLL AVG)
DMR, Limited - Numeric Violation
December 31, 2024
Mercury, total recoverable
227% over limit
Discharged 0.00000622 mg/L against a permitted limit of 0.0000019 mg/L (ROLL AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
0% over limit
Discharged 6 mg/L against a permitted limit of 15 mg/L (MX WK AV)
DMR, Limited - Overdue
BOD, carbonaceous [5 day, 20 C]
0% over limit
Discharged 5 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Overdue
November 30, 2024
Nitrogen, ammonia total [as N]
82% over limit
Discharged 6.19 mg/L against a permitted limit of 3.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
October 31, 2024
Mercury, total recoverable
361% over limit
Discharged 0.00000876 mg/L against a permitted limit of 0.0000019 mg/L (ROLL AVG)
DMR, Limited - Numeric Violation
September 30, 2024
Toxicity [chronic], Ceriodaphnia dubia
0% over limit
Discharged 0 toxic against a permitted limit of 1 toxic (MAXIMUM)
DMR, Limited - Overdue
Toxicity [chronic], Pimephales promelas [Fathead Minnow]
0% over limit
Discharged 0 toxic against a permitted limit of 1 toxic (MAXIMUM)
DMR, Limited - Overdue
Toxicity [acute], Ceriodaphnia dubia
0% over limit
Discharged 0 toxic against a permitted limit of 1 toxic (MAXIMUM)
DMR, Limited - Overdue
Toxicity [acute], Pimephales promelas [Fathead Minnow]
0% over limit
Discharged 0 toxic against a permitted limit of 1 toxic (MAXIMUM)
DMR, Limited - Overdue
August 31, 2024
Mercury, total recoverable
273% over limit
Discharged 0.00000708 mg/L against a permitted limit of 0.0000019 mg/L (ROLL AVG)
DMR, Limited - Numeric Violation
First flagged
April 14, 2026 (3 months ago)
Last confirmed
August 1, 2026 (5 days ago)