OSAGE CITY OF STP
NPDES ID: IA0032956
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: 3 effluent violations.
Violations
May 31, 2026
Copper, total [as Cu]
24% over limit
Discharged 0.02175 mg/L against a permitted limit of 0.01757 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
Copper, total [as Cu]
15% over limit
Discharged 0.031 mg/L against a permitted limit of 0.027 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
April 30, 2026
Nitrogen, ammonia total [as N]
26% over limit
Discharged 2.270011 mg/L against a permitted limit of 1.8 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
March 31, 2026
Nitrogen, ammonia total [as N]
5% over limit
Discharged 10.40972051 kg/d against a permitted limit of 9.94259992 kg/d (30DA AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
160% over limit
Discharged 6.509511 mg/L against a permitted limit of 2.5 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
61% over limit
Discharged 293.53755653 kg/d against a permitted limit of 182.50799847 kg/d (7 DA AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
131% over limit
Discharged 34 mg/L against a permitted limit of 14.7 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Solids, total suspended
117% over limit
Discharged 65 mg/L against a permitted limit of 30 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
289% over limit
Discharged 175 mg/L against a permitted limit of 45 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
February 28, 2026
Copper, total [as Cu]
26% over limit
Discharged 0.034 mg/L against a permitted limit of 0.027 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Solids, total suspended
2% over limit
Discharged 46 mg/L against a permitted limit of 45 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
January 31, 2026
Nitrogen, ammonia total [as N]
31% over limit
Discharged 21.29699908 kg/d against a permitted limit of 16.25319986 kg/d (30DA AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
240% over limit
Discharged 13.94677 mg/L against a permitted limit of 4.1 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
96% over limit
Discharged 30 mg/L against a permitted limit of 15.3 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
December 31, 2025
Nitrogen, ammonia total [as N]
373% over limit
Discharged 14.17831 mg/L against a permitted limit of 3 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
50% over limit
Discharged 24 mg/L against a permitted limit of 16 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
E. coli
233% over limit
Discharged 419.7289 MPN/100mL against a permitted limit of 126 MPN/100mL (GEO MEAN)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
79% over limit
Discharged 21.096549 kg/d against a permitted limit of 11.8039999 kg/d (30DA AVG)
DMR, Limited - Numeric Violation
November 30, 2025
Nitrogen, ammonia total [as N]
43% over limit
Discharged 21 mg/L against a permitted limit of 14.7 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
63% over limit
Discharged 18.00527211 kg/d against a permitted limit of 11.07759991 kg/d (30DA AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
324% over limit
Discharged 11.86621 mg/L against a permitted limit of 2.8 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
September 30, 2025
E. coli
76% over limit
Discharged 221.7958 MPN/100mL against a permitted limit of 126 MPN/100mL (GEO MEAN)
DMR, Limited - Numeric Violation
Copper, total [as Cu]
27% over limit
Discharged 0.02225 mg/L against a permitted limit of 0.01757 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
August 31, 2025
Copper, total [as Cu]
25% over limit
Discharged 0.022 mg/L against a permitted limit of 0.01757 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
July 31, 2025
Copper, total [as Cu]
36% over limit
Discharged 0.09672969 kg/d against a permitted limit of 0.0709602 kg/d (30DA AVG)
DMR, Limited - Numeric Violation
Copper, total [as Cu]
156% over limit
Discharged 0.27970577 kg/d against a permitted limit of 0.1094594 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Copper, total [as Cu]
73% over limit
Discharged 0.0304 mg/L against a permitted limit of 0.01757 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
Copper, total [as Cu]
78% over limit
Discharged 0.048 mg/L against a permitted limit of 0.027 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, total [as N]
64% over limit
Discharged 291.36039955 kg/d against a permitted limit of 177.74099851 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
June 30, 2025
Nitrogen, ammonia total [as N]
30% over limit
Discharged 2.073187 mg/L against a permitted limit of 1.6 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
Copper, total [as Cu]
21% over limit
Discharged 0.02125 mg/L against a permitted limit of 0.01757 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
May 31, 2025
Copper, total [as Cu]
7% over limit
Discharged 0.01875 mg/L against a permitted limit of 0.01757 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
December 31, 2024
Copper, total [as Cu]
7% over limit
Discharged 0.01875 mg/L against a permitted limit of 0.01757 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
November 30, 2024
Copper, total [as Cu]
39% over limit
Discharged 0.0245 mg/L against a permitted limit of 0.01757 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
October 31, 2024
E. coli
49% over limit
Discharged 188.332 MPN/100mL against a permitted limit of 126 MPN/100mL (GEO MEAN)
DMR, Limited - Numeric Violation
Copper, total [as Cu]
33% over limit
Discharged 0.036 mg/L against a permitted limit of 0.027 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Copper, total [as Cu]
74% over limit
Discharged 0.0306 mg/L against a permitted limit of 0.01757 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
September 30, 2024
Copper, total [as Cu]
61% over limit
Discharged 0.02825 mg/L against a permitted limit of 0.01757 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
Copper, total [as Cu]
15% over limit
Discharged 0.031 mg/L against a permitted limit of 0.027 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
August 31, 2024
Copper, total [as Cu]
52% over limit
Discharged 0.041 mg/L against a permitted limit of 0.027 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Copper, total [as Cu]
101% over limit
Discharged 0.03525 mg/L against a permitted limit of 0.01757 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
July 31, 2024
Copper, total [as Cu]
11% over limit
Discharged 0.03 mg/L against a permitted limit of 0.027 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Copper, total [as Cu]
29% over limit
Discharged 0.022676 mg/L against a permitted limit of 0.01757 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
First flagged
April 14, 2026 (3 months ago)
Last confirmed
July 13, 2026 (23 days ago)