ZEIGLER STP, CITY OF
NPDES ID: IL0023299
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.
Violations
May 31, 2026
BOD, carbonaceous [5 day, 20 C]
12% over limit
Discharged 28 mg/L against a permitted limit of 25 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
49% over limit
Discharged 67 mg/L against a permitted limit of 45 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
81% over limit
Discharged 67 mg/L against a permitted limit of 37 mg/L (MO AVG)
DMR, Limited - Numeric Violation
April 30, 2026
BOD, carbonaceous [5 day, 20 C]
44% over limit
Discharged 36 mg/L against a permitted limit of 25 mg/L (MO AVG)
DMR, Limited - Numeric Violation
March 31, 2026
BOD, carbonaceous [5 day, 20 C]
48% over limit
Discharged 37 mg/L against a permitted limit of 25 mg/L (MO AVG)
DMR, Limited - Numeric Violation
February 28, 2026
BOD, carbonaceous [5 day, 20 C]
8% over limit
Discharged 27 mg/L against a permitted limit of 25 mg/L (MO AVG)
DMR, Limited - Numeric Violation
January 31, 2026
Solids, total suspended
11% over limit
Discharged 50 mg/L against a permitted limit of 45 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
84% over limit
Discharged 46 mg/L against a permitted limit of 25 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
15% over limit
Discharged 46 mg/L against a permitted limit of 40 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
35% over limit
Discharged 50 mg/L against a permitted limit of 37 mg/L (MO AVG)
DMR, Limited - Numeric Violation
December 31, 2025
BOD, carbonaceous [5 day, 20 C]
32% over limit
Discharged 33 mg/L against a permitted limit of 25 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
19% over limit
Discharged 124.84999895 kg/d against a permitted limit of 105.32799911 kg/d (MO AVG)
DMR, Limited - Numeric Violation
October 31, 2025
Solids, total suspended
278% over limit
Discharged 140 mg/L against a permitted limit of 37 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
211% over limit
Discharged 140 mg/L against a permitted limit of 45 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
September 30, 2025
Solids, total suspended
103% over limit
Discharged 75 mg/L against a permitted limit of 37 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
67% over limit
Discharged 75 mg/L against a permitted limit of 45 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
July 31, 2025
pH
0% over limit
Discharged 9.2 SU against a permitted limit of 9 SU (MAXIMUM)
DMR, Limited - Numeric Violation
June 30, 2025
Coliform, fecal general
38% over limit
Discharged 550 MPN/100mL against a permitted limit of 400 MPN/100mL (DAILY MX)
DMR, Limited - Numeric Violation
May 31, 2025
Solids, total suspended
41% over limit
Discharged 52 mg/L against a permitted limit of 37 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
16% over limit
Discharged 52 mg/L against a permitted limit of 45 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
Chlorine, total residual
280% over limit
Discharged 0.19 mg/L against a permitted limit of 0.05 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Coliform, fecal general
1275% over limit
Discharged 5500 MPN/100mL against a permitted limit of 400 MPN/100mL (DAILY MX)
DMR, Limited - Numeric Violation
April 30, 2025
Chlorine, total residual
260% over limit
Discharged 0.18 mg/L against a permitted limit of 0.05 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
March 31, 2025
BOD, carbonaceous [5 day, 20 C]
28% over limit
Discharged 51.1 mg/L against a permitted limit of 40 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
14% over limit
Discharged 42 mg/L against a permitted limit of 37 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
104% over limit
Discharged 51.1 mg/L against a permitted limit of 25 mg/L (MO AVG)
DMR, Limited - Numeric Violation
February 28, 2025
Chlorine, total residual
120% over limit
Discharged 0.11 mg/L against a permitted limit of 0.05 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Solids, total suspended
35% over limit
Discharged 50 mg/L against a permitted limit of 37 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
5% over limit
Discharged 110.32199907 kg/d against a permitted limit of 105.32799911 kg/d (MO AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
44% over limit
Discharged 36 mg/L against a permitted limit of 25 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
11% over limit
Discharged 50 mg/L against a permitted limit of 45 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
January 31, 2025
pH
0% over limit
Discharged 9.5 SU against a permitted limit of 9 SU (MAXIMUM)
DMR, Limited - Numeric Violation
Chlorine, total residual
40% over limit
Discharged 0.07 mg/L against a permitted limit of 0.05 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
December 31, 2024
Solids, total suspended
54% over limit
Discharged 57 mg/L against a permitted limit of 37 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
457% over limit
Discharged 139.2 mg/L against a permitted limit of 25 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
27% over limit
Discharged 57 mg/L against a permitted limit of 45 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
248% over limit
Discharged 139.2 mg/L against a permitted limit of 40 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
Chlorine, total residual
120% over limit
Discharged 0.11 mg/L against a permitted limit of 0.05 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
November 30, 2024
Solids, total suspended
62% over limit
Discharged 60 mg/L against a permitted limit of 37 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
13422% over limit
Discharged 6085 mg/L against a permitted limit of 45 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
October 31, 2024
Solids, total suspended
54% over limit
Discharged 57 mg/L against a permitted limit of 37 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
27% over limit
Discharged 57 mg/L against a permitted limit of 45 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
September 30, 2024
Coliform, fecal general
9% over limit
Discharged 435 MPN/100mL against a permitted limit of 400 MPN/100mL (DAILY MX)
DMR, Limited - Numeric Violation
August 31, 2024
Coliform, fecal general
505% over limit
Discharged 2420 MPN/100mL against a permitted limit of 400 MPN/100mL (DAILY MX)
DMR, Limited - Numeric Violation
First flagged
April 14, 2026 (3 months ago)
Last confirmed
August 1, 2026 (6 days ago)