WAPATO, CITY OF - WAPATO WWTP
NPDES ID: WA0050229
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: 12 effluent violations.
Violations
May 31, 2026
Nitrogen, ammonia total [as N]
146% over limit
Discharged 6.4 mg/L against a permitted limit of 2.6 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Zinc, total recoverable
33% over limit
Discharged 0.069 mg/L against a permitted limit of 0.052 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
4% over limit
Discharged 3.31419997 kg/d against a permitted limit of 3.17799997 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
129% over limit
Discharged 1.6 mg/L against a permitted limit of 0.7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Zinc, total recoverable
64% over limit
Discharged 0.041 mg/L against a permitted limit of 0.025 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
17% over limit
Discharged 13.30219989 kg/d against a permitted limit of 11.3499999 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
April 30, 2026
Nitrogen, ammonia total [as N]
17% over limit
Discharged 0.82 mg/L against a permitted limit of 0.7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Zinc, total recoverable
13% over limit
Discharged 0.12258 kg/d against a permitted limit of 0.10896 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Zinc, total recoverable
20% over limit
Discharged 0.2724 kg/d against a permitted limit of 0.227 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Zinc, total recoverable
169% over limit
Discharged 0.14000001 mg/L against a permitted limit of 0.052 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Zinc, total recoverable
152% over limit
Discharged 0.063 mg/L against a permitted limit of 0.025 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
58% over limit
Discharged 4.1 mg/L against a permitted limit of 2.6 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
March 31, 2026
Zinc, total recoverable
99% over limit
Discharged 0.04975 mg/L against a permitted limit of 0.025 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Zinc, total recoverable
19% over limit
Discharged 0.062 mg/L against a permitted limit of 0.052 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
February 28, 2026
Zinc, total recoverable
460% over limit
Discharged 0.14000001 mg/L against a permitted limit of 0.025 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Zinc, total recoverable
419% over limit
Discharged 0.27000001 mg/L against a permitted limit of 0.052 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Zinc, total recoverable
162% over limit
Discharged 0.285112 kg/d against a permitted limit of 0.10896 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Zinc, total recoverable
156% over limit
Discharged 0.58112 kg/d against a permitted limit of 0.227 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
January 31, 2026
Zinc, total recoverable
376% over limit
Discharged 0.11900001 mg/L against a permitted limit of 0.025 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Zinc, total recoverable
381% over limit
Discharged 0.25000001 mg/L against a permitted limit of 0.052 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Zinc, total recoverable
137% over limit
Discharged 0.258326 kg/d against a permitted limit of 0.10896 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Zinc, total recoverable
136% over limit
Discharged 0.53572 kg/d against a permitted limit of 0.227 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
December 31, 2025
Zinc, total recoverable
1192% over limit
Discharged 0.67200003 mg/L against a permitted limit of 0.052 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Zinc, total recoverable
22% over limit
Discharged 0.276486 kg/d against a permitted limit of 0.227 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Zinc, total recoverable
883% over limit
Discharged 1.07143999 kg/d against a permitted limit of 0.10896 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Zinc, total recoverable
950% over limit
Discharged 0.26260001 mg/L against a permitted limit of 0.025 mg/L (MO AVG)
DMR, Limited - Numeric Violation
November 30, 2025
Zinc, total recoverable
15% over limit
Discharged 0.125304 kg/d against a permitted limit of 0.10896 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Zinc, total recoverable
35% over limit
Discharged 0.07 mg/L against a permitted limit of 0.052 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Zinc, total recoverable
125% over limit
Discharged 0.05625 mg/L against a permitted limit of 0.025 mg/L (MO AVG)
DMR, Limited - Numeric Violation
October 31, 2025
Nitrogen, ammonia total [as N]
233% over limit
Discharged 37.81819968 kg/d against a permitted limit of 11.3499999 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Zinc, total recoverable
42% over limit
Discharged 0.15436 kg/d against a permitted limit of 0.10896 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
259% over limit
Discharged 11.4135599 kg/d against a permitted limit of 3.17799997 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Zinc, total recoverable
179% over limit
Discharged 0.0698 mg/L against a permitted limit of 0.025 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
657% over limit
Discharged 5.3 mg/L against a permitted limit of 0.7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Zinc, total recoverable
85% over limit
Discharged 0.41995 kg/d against a permitted limit of 0.227 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Zinc, total recoverable
285% over limit
Discharged 0.20000001 mg/L against a permitted limit of 0.052 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
592% over limit
Discharged 18 mg/L against a permitted limit of 2.6 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
September 30, 2025
Nitrogen, ammonia total [as N]
231% over limit
Discharged 37.54579968 kg/d against a permitted limit of 11.3499999 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
457% over limit
Discharged 17.70145985 kg/d against a permitted limit of 3.17799997 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Zinc, total recoverable
18% over limit
Discharged 0.0295 mg/L against a permitted limit of 0.025 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
477% over limit
Discharged 15 mg/L against a permitted limit of 2.6 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
981% over limit
Discharged 7.57 mg/L against a permitted limit of 0.7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
August 31, 2025
Zinc, total recoverable
36% over limit
Discharged 0.034 mg/L against a permitted limit of 0.025 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
1216% over limit
Discharged 41.83609965 kg/d against a permitted limit of 3.17799997 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
442% over limit
Discharged 61.56239948 kg/d against a permitted limit of 11.3499999 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
823% over limit
Discharged 24 mg/L against a permitted limit of 2.6 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
2579% over limit
Discharged 18.75 mg/L against a permitted limit of 0.7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
July 31, 2025
Nitrogen, ammonia total [as N]
472% over limit
Discharged 64.92199945 kg/d against a permitted limit of 11.3499999 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
E. coli, MTEC-MF
233% over limit
Discharged 665 MPN/100mL against a permitted limit of 200 MPN/100mL (INST MAX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
977% over limit
Discharged 28 mg/L against a permitted limit of 2.6 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Zinc, total recoverable
40% over limit
Discharged 0.035 mg/L against a permitted limit of 0.025 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
2500% over limit
Discharged 18.2 mg/L against a permitted limit of 0.7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Zinc, total recoverable
19% over limit
Discharged 0.062 mg/L against a permitted limit of 0.052 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
1290% over limit
Discharged 44.18327963 kg/d against a permitted limit of 3.17799997 kg/d (MO AVG)
DMR, Limited - Numeric Violation
June 30, 2025
Nitrogen, ammonia total [as N]
900% over limit
Discharged 47.2159996 kg/d against a permitted limit of 4.72159996 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
746% over limit
Discharged 22 mg/L against a permitted limit of 2.6 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
1386% over limit
Discharged 47.2159996 kg/d against a permitted limit of 3.17799997 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Zinc, total recoverable
569% over limit
Discharged 0.16725001 mg/L against a permitted limit of 0.025 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
1605% over limit
Discharged 18.75 mg/L against a permitted limit of 1.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
2579% over limit
Discharged 18.75 mg/L against a permitted limit of 0.7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Zinc, total recoverable
308% over limit
Discharged 0.92615999 kg/d against a permitted limit of 0.227 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
392% over limit
Discharged 55.84199953 kg/d against a permitted limit of 11.3499999 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Zinc, total recoverable
612% over limit
Discharged 0.37000002 mg/L against a permitted limit of 0.052 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
135% over limit
Discharged 55.84199953 kg/d against a permitted limit of 23.7441998 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
307% over limit
Discharged 22 mg/L against a permitted limit of 5.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Zinc, total recoverable
285% over limit
Discharged 0.419042 kg/d against a permitted limit of 0.10896 kg/d (MO AVG)
DMR, Limited - Numeric Violation
May 31, 2025
Nitrogen, ammonia total [as N]
1054% over limit
Discharged 30 mg/L against a permitted limit of 2.6 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Zinc, total recoverable
80% over limit
Discharged 0.045 mg/L against a permitted limit of 0.025 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Zinc, total recoverable
4% over limit
Discharged 0.1135 kg/d against a permitted limit of 0.10896 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Zinc, total recoverable
112% over limit
Discharged 0.11000001 mg/L against a permitted limit of 0.052 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
554% over limit
Discharged 74.27439938 kg/d against a permitted limit of 11.3499999 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
E. coli, MTEC-MF
13% over limit
Discharged 225 MPN/100mL against a permitted limit of 200 MPN/100mL (INST MAX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
2468% over limit
Discharged 17.975 mg/L against a permitted limit of 0.7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Zinc, total recoverable
20% over limit
Discharged 0.2724 kg/d against a permitted limit of 0.227 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
1347% over limit
Discharged 45.97657961 kg/d against a permitted limit of 3.17799997 kg/d (MO AVG)
DMR, Limited - Numeric Violation
April 30, 2025
Nitrogen, ammonia total [as N]
581% over limit
Discharged 77.27079935 kg/d against a permitted limit of 11.3499999 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
1568% over limit
Discharged 53.00903955 kg/d against a permitted limit of 3.17799997 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
2900% over limit
Discharged 21 mg/L against a permitted limit of 0.7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
977% over limit
Discharged 28 mg/L against a permitted limit of 2.6 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
March 31, 2025
Nitrogen, ammonia total [as N]
65% over limit
Discharged 39.27099967 kg/d against a permitted limit of 23.7441998 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
289% over limit
Discharged 21 mg/L against a permitted limit of 5.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
1109% over limit
Discharged 13.3 mg/L against a permitted limit of 1.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
489% over limit
Discharged 27.79841977 kg/d against a permitted limit of 4.72159996 kg/d (MO AVG)
DMR, Limited - Numeric Violation
February 28, 2025
Nitrogen, ammonia total [as N]
270% over limit
Discharged 20 mg/L against a permitted limit of 5.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Zinc, total recoverable
50% over limit
Discharged 0.3405 kg/d against a permitted limit of 0.227 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
1309% over limit
Discharged 15.5 mg/L against a permitted limit of 1.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Phosphorus, total [as P]
0% over limit
Discharged 0 kg/d against a permitted limit of 0 kg/d (DAILY MX)
DMR, Monitor Only - Overdue
Nitrogen, ammonia total [as N]
614% over limit
Discharged 33.73219972 kg/d against a permitted limit of 4.72159996 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Phosphorus, total [as P]
0% over limit
Discharged 0 mg/L against a permitted limit of 0 mg/L (DAILY MX)
DMR, Monitor Only - Overdue
Phosphorus, total [as P]
0% over limit
Discharged 0 kg/d against a permitted limit of 0 kg/d (MO AVG)
DMR, Monitor Only - Overdue
Phosphorus, total [as P]
0% over limit
Discharged 0 mg/L against a permitted limit of 0 mg/L (MO AVG)
DMR, Monitor Only - Overdue
Nitrogen, ammonia total [as N]
95% over limit
Discharged 46.30799961 kg/d against a permitted limit of 23.7441998 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Zinc, total recoverable
42% over limit
Discharged 0.15436 kg/d against a permitted limit of 0.10896 kg/d (MO AVG)
DMR, Limited - Numeric Violation
January 31, 2025
Nitrogen, ammonia total [as N]
1164% over limit
Discharged 13.9 mg/L against a permitted limit of 1.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
289% over limit
Discharged 21 mg/L against a permitted limit of 5.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
37% over limit
Discharged 32.41559973 kg/d against a permitted limit of 23.7441998 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Zinc, total recoverable
94% over limit
Discharged 0.44038 kg/d against a permitted limit of 0.227 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Zinc, total recoverable
138% over limit
Discharged 0.25878 kg/d against a permitted limit of 0.10896 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
480% over limit
Discharged 27.37619977 kg/d against a permitted limit of 4.72159996 kg/d (MO AVG)
DMR, Limited - Numeric Violation
December 31, 2024
Nitrogen, ammonia total [as N]
1018% over limit
Discharged 12.3 mg/L against a permitted limit of 1.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
PER-AND POLYFLUOROALKYL SUBSTANCES
0% over limit
Discharged 0 mg/L against a permitted limit of 0 mg/L (ANNL AVG)
DMR, Monitor Only - Overdue
Nitrogen, ammonia total [as N]
410% over limit
Discharged 24.0619998 kg/d against a permitted limit of 4.72159996 kg/d (MO AVG)
DMR, Limited - Numeric Violation
PER-AND POLYFLUOROALKYL SUBSTANCES
0% over limit
Discharged 0.0000096 mg/L against a permitted limit of 0 mg/L (ANNL AVG)
DMR, Monitor Only - Overdue
Nitrogen, ammonia total [as N]
20% over limit
Discharged 28.37499976 kg/d against a permitted limit of 23.7441998 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
PER-AND POLYFLUOROALKYL SUBSTANCES
0% over limit
Discharged 0.0000096 mg/L against a permitted limit of 0 mg/L (DAILY MX)
DMR, Monitor Only - Overdue
Toxicity [acute], Pimephales promelas [Fathead Minnow]
0% over limit
Discharged 1 toxic against a permitted limit of 0 toxic (DAILY MX)
DMR, Monitor Only - Overdue
PER-AND POLYFLUOROALKYL SUBSTANCES
0% over limit
Discharged 145.49 mg/L against a permitted limit of 0 mg/L (DAILY MX)
DMR, Monitor Only - Overdue
PER-AND POLYFLUOROALKYL SUBSTANCES
0% over limit
Discharged 145.49 mg/L against a permitted limit of 0 mg/L (MO AVG)
DMR, Monitor Only - Overdue
Nitrogen, ammonia total [as N]
196% over limit
Discharged 16 mg/L against a permitted limit of 5.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
PER-AND POLYFLUOROALKYL SUBSTANCES
0% over limit
Discharged 0 mg/L against a permitted limit of 0 mg/L (DAILY MX)
DMR, Monitor Only - Overdue
Toxicity [acute], Ceriodaphnia dubia
0% over limit
Discharged 1 toxic against a permitted limit of 0 toxic (DAILY MX)
DMR, Monitor Only - Overdue
November 30, 2024
Nitrogen, ammonia total [as N]
169% over limit
Discharged 14.5 mg/L against a permitted limit of 5.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
279% over limit
Discharged 17.88759985 kg/d against a permitted limit of 4.72159996 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
23% over limit
Discharged 29.09685976 kg/d against a permitted limit of 23.7441998 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
679% over limit
Discharged 8.57 mg/L against a permitted limit of 1.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
October 31, 2024
Nitrogen, ammonia total [as N]
459% over limit
Discharged 17.77863985 kg/d against a permitted limit of 3.17799997 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
146% over limit
Discharged 27.92099977 kg/d against a permitted limit of 11.3499999 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
335% over limit
Discharged 11.3 mg/L against a permitted limit of 2.6 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
971% over limit
Discharged 7.5 mg/L against a permitted limit of 0.7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
September 30, 2024
Nitrogen, ammonia total [as N]
9% over limit
Discharged 3.45039997 kg/d against a permitted limit of 3.17799997 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
89% over limit
Discharged 1.32 mg/L against a permitted limit of 0.7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
August 31, 2024
Nitrogen, ammonia total [as N]
472% over limit
Discharged 64.87659945 kg/d against a permitted limit of 11.3499999 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
1374% over limit
Discharged 46.85279961 kg/d against a permitted limit of 3.17799997 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Zinc, total recoverable
65620% over limit
Discharged 149.18439875 kg/d against a permitted limit of 0.227 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
1015% over limit
Discharged 29 mg/L against a permitted limit of 2.6 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Zinc, total recoverable
136817% over limit
Discharged 149.18439875 kg/d against a permitted limit of 0.10896 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
2893% over limit
Discharged 20.95 mg/L against a permitted limit of 0.7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
First flagged
April 14, 2026 (3 months ago)
Last confirmed
July 13, 2026 (24 days ago)