DELPHI WWTP
NPDES ID: IN0021377
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: 4 effluent violations, 2 single-event violations.
Violations
May 31, 2026
Phosphorus, total [as P]
75% over limit
Discharged 1.752 mg/L against a permitted limit of 1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
April 30, 2026
Phosphorus, total [as P]
115% over limit
Discharged 2.153 mg/L against a permitted limit of 1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
March 31, 2026
Phosphorus, total [as P]
118% over limit
Discharged 2.178 mg/L against a permitted limit of 1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
February 28, 2026
Phosphorus, total [as P]
219% over limit
Discharged 3.193 mg/L against a permitted limit of 1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
January 31, 2026
Phosphorus, total [as P]
217% over limit
Discharged 3.173 mg/L against a permitted limit of 1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
December 31, 2025
Phosphorus, total [as P]
221% over limit
Discharged 3.212 mg/L against a permitted limit of 1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
November 30, 2025
Phosphorus, total [as P]
159% over limit
Discharged 2.586 mg/L against a permitted limit of 1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
October 31, 2025
Phosphorus, total [as P]
187% over limit
Discharged 2.87 mg/L against a permitted limit of 1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
September 30, 2025
Phosphorus, total [as P]
258% over limit
Discharged 3.582 mg/L against a permitted limit of 1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
E. coli, colony forming units [CFU]
0% over limit
Discharged 98.8 MPN/100mL against a permitted limit of 235 MPN/100mL (DAILY MX)
DMR, Limited - Overdue
August 31, 2025
Phosphorus, total [as P]
256% over limit
Discharged 3.561 mg/L against a permitted limit of 1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
July 31, 2025
Phosphorus, total [as P]
204% over limit
Discharged 3.035 mg/L against a permitted limit of 1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
June 30, 2025
Phosphorus, total [as P]
25% over limit
Discharged 1.247 mg/L against a permitted limit of 1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
331% over limit
Discharged 56.29599953 kg/d against a permitted limit of 13.07519989 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
569% over limit
Discharged 15.39 mg/L against a permitted limit of 2.3 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
899% over limit
Discharged 34.98 mg/L against a permitted limit of 3.5 mg/L (MX WK AV)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
544% over limit
Discharged 128.05977892 kg/d against a permitted limit of 19.88519983 kg/d (MX WK AV)
DMR, Limited - Numeric Violation
May 31, 2025
Nitrogen, ammonia total [as N]
980% over limit
Discharged 24.85 mg/L against a permitted limit of 2.3 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
487% over limit
Discharged 116.73701902 kg/d against a permitted limit of 19.88519983 kg/d (MX WK AV)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
824% over limit
Discharged 32.34 mg/L against a permitted limit of 3.5 mg/L (MX WK AV)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
534% over limit
Discharged 82.9457993 kg/d against a permitted limit of 13.07519989 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Phosphorus, total [as P]
38% over limit
Discharged 1.376 mg/L against a permitted limit of 1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
April 30, 2025
Nitrogen, ammonia total [as N]
103% over limit
Discharged 79.54533933 kg/d against a permitted limit of 39.22559967 kg/d (MX WK AV)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
60% over limit
Discharged 41.95867965 kg/d against a permitted limit of 26.15039978 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
218% over limit
Discharged 21.93 mg/L against a permitted limit of 6.9 mg/L (MX WK AV)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
130% over limit
Discharged 10.59 mg/L against a permitted limit of 4.6 mg/L (MO AVG)
DMR, Limited - Numeric Violation
January 31, 2025
Phosphorus, total [as P]
68% over limit
Discharged 1.684 mg/L against a permitted limit of 1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
December 31, 2024
Phosphorus, total [as P]
53% over limit
Discharged 1.533 mg/L against a permitted limit of 1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
November 30, 2024
Phosphorus, total [as P]
6% over limit
Discharged 1.058 mg/L against a permitted limit of 1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
October 31, 2024
Phosphorus, total [as P]
60% over limit
Discharged 1.6 mg/L against a permitted limit of 1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
September 30, 2024
Phosphorus, total [as P]
20% over limit
Discharged 1.195 mg/L against a permitted limit of 1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
First flagged
April 14, 2026 (3 months ago)
Last confirmed
August 1, 2026 (6 days ago)