CITY OF ALTO WWTP
NPDES ID: TX0142697
S — SNC: Compliance schedule violation
The facility missed a deadline in its compliance schedule by more than 90 days.
This quarter: 8 effluent violations.
Violations
May 31, 2026
Nitrogen, ammonia total [as N]
1% over limit
Discharged 15.1 mg/L against a permitted limit of 15 mg/L (SINGGRAB)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
16% over limit
Discharged 4.2 mg/L against a permitted limit of 5 mg/L (MO MIN)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
271% over limit
Discharged 11.12 mg/L against a permitted limit of 3 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
April 30, 2026
Nitrogen, ammonia total [as N]
16% over limit
Discharged 17.4 mg/L against a permitted limit of 15 mg/L (SINGGRAB)
DMR, Limited - Numeric Violation
pH
0% over limit
Discharged 5 SU against a permitted limit of 6 SU (MINIMUM)
DMR, Limited - Numeric Violation
Solids, total suspended
16% over limit
Discharged 17.4 mg/L against a permitted limit of 15 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
76% over limit
Discharged 1.2 mg/L against a permitted limit of 5 mg/L (MO MIN)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
327% over limit
Discharged 12.82 mg/L against a permitted limit of 3 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
March 31, 2026
Nitrogen, ammonia total [as N]
67% over limit
Discharged 5 mg/L against a permitted limit of 3 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
4% over limit
Discharged 4.8 mg/L against a permitted limit of 5 mg/L (MO MIN)
DMR, Limited - Numeric Violation
February 28, 2026
Solids, total suspended
5% over limit
Discharged 15.8 mg/L against a permitted limit of 15 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
196% over limit
Discharged 8.89 mg/L against a permitted limit of 3 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
12% over limit
Discharged 11.2 mg/L against a permitted limit of 10 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
January 31, 2026
Nitrogen, ammonia total [as N]
426% over limit
Discharged 15.78 mg/L against a permitted limit of 3 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
Solids, total suspended
15% over limit
Discharged 17.2 mg/L against a permitted limit of 15 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
43% over limit
Discharged 21.4 mg/L against a permitted limit of 15 mg/L (SINGGRAB)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
18% over limit
Discharged 4.1 mg/L against a permitted limit of 5 mg/L (MO MIN)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
83% over limit
Discharged 18.3 mg/L against a permitted limit of 10 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
December 31, 2025
BOD, carbonaceous [5 day, 20 C]
10% over limit
Discharged 11 mg/L against a permitted limit of 10 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
180% over limit
Discharged 8.39 mg/L against a permitted limit of 3 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
November 30, 2025
E. coli
0% over limit
Discharged 0 MPN/100mL against a permitted limit of 126 MPN/100mL (DAILY AV)
DMR, Limited - Overdue
Nitrogen, ammonia total [as N]
130% over limit
Discharged 34.5 mg/L against a permitted limit of 15 mg/L (SINGGRAB)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
39% over limit
Discharged 48.8 mg/L against a permitted limit of 35 mg/L (SINGGRAB)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
129% over limit
Discharged 22.9 mg/L against a permitted limit of 10 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
E. coli
0% over limit
Discharged 0 MPN/100mL against a permitted limit of 399 MPN/100mL (SINGGRAB)
DMR, Limited - Overdue
Nitrogen, ammonia total [as N]
414% over limit
Discharged 15.42 mg/L against a permitted limit of 3 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
10% over limit
Discharged 4.5 mg/L against a permitted limit of 5 mg/L (MO MIN)
DMR, Limited - Numeric Violation
October 31, 2025
BOD, carbonaceous [5 day, 20 C]
27% over limit
Discharged 12.7 mg/L against a permitted limit of 10 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
25% over limit
Discharged 18.8 mg/L against a permitted limit of 15 mg/L (SINGGRAB)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
40% over limit
Discharged 4.21 mg/L against a permitted limit of 3 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
18% over limit
Discharged 4.1 mg/L against a permitted limit of 5 mg/L (MO MIN)
DMR, Limited - Numeric Violation
September 30, 2025
E. coli
507% over limit
Discharged 2420 MPN/100mL against a permitted limit of 399 MPN/100mL (SINGGRAB)
DMR, Limited - Numeric Violation
E. coli
1821% over limit
Discharged 2420 MPN/100mL against a permitted limit of 126 MPN/100mL (DAILY AV)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
3% over limit
Discharged 10.3 mg/L against a permitted limit of 10 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
August 31, 2025
Nitrogen, ammonia total [as N]
487% over limit
Discharged 17.62 mg/L against a permitted limit of 3 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
90% over limit
Discharged 19 mg/L against a permitted limit of 10 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
38% over limit
Discharged 20.7 mg/L against a permitted limit of 15 mg/L (SINGGRAB)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
12% over limit
Discharged 4.4 mg/L against a permitted limit of 5 mg/L (MO MIN)
DMR, Limited - Numeric Violation
July 31, 2025
BOD, carbonaceous [5 day, 20 C]
69% over limit
Discharged 16.9 mg/L against a permitted limit of 10 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
43% over limit
Discharged 21.4 mg/L against a permitted limit of 15 mg/L (SINGGRAB)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
454% over limit
Discharged 16.62 mg/L against a permitted limit of 3 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
20% over limit
Discharged 4 mg/L against a permitted limit of 5 mg/L (MO MIN)
DMR, Limited - Numeric Violation
June 30, 2025
Oxygen, dissolved [DO]
20% over limit
Discharged 4 mg/L against a permitted limit of 5 mg/L (MO MIN)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
66% over limit
Discharged 4.98 mg/L against a permitted limit of 3 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
May 31, 2025
Nitrogen, ammonia total [as N]
64% over limit
Discharged 4.91 mg/L against a permitted limit of 3 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
Solids, total suspended
13% over limit
Discharged 17 mg/L against a permitted limit of 15 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
Chlorine, total residual
20% over limit
Discharged 0.8 mg/L against a permitted limit of 1 mg/L (MO MIN)
DMR, Limited - Numeric Violation
April 30, 2025
Oxygen, dissolved [DO]
14% over limit
Discharged 4.3 mg/L against a permitted limit of 5 mg/L (MO MIN)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
353% over limit
Discharged 13.6 mg/L against a permitted limit of 3 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
14% over limit
Discharged 11.4 mg/L against a permitted limit of 10 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
33% over limit
Discharged 20 mg/L against a permitted limit of 15 mg/L (SINGGRAB)
DMR, Limited - Numeric Violation
March 31, 2025
BOD, carbonaceous [5 day, 20 C]
10% over limit
Discharged 11 mg/L against a permitted limit of 10 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
135% over limit
Discharged 7.06 mg/L against a permitted limit of 3 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
February 28, 2025
Nitrogen, ammonia total [as N]
18% over limit
Discharged 3.55 mg/L against a permitted limit of 3 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
January 31, 2025
Nitrogen, ammonia total [as N]
32% over limit
Discharged 3.96 mg/L against a permitted limit of 3 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
Solids, total suspended
41% over limit
Discharged 21.1 mg/L against a permitted limit of 15 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
December 31, 2024
Solids, total suspended
41% over limit
Discharged 84.3 mg/L against a permitted limit of 60 mg/L (SINGGRAB)
DMR, Limited - Numeric Violation
Solids, total suspended
111% over limit
Discharged 31.6 mg/L against a permitted limit of 15 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
E. coli
254% over limit
Discharged 1414 MPN/100mL against a permitted limit of 399 MPN/100mL (SINGGRAB)
DMR, Limited - Numeric Violation
E. coli
1022% over limit
Discharged 1414 MPN/100mL against a permitted limit of 126 MPN/100mL (DAILY AV)
DMR, Limited - Numeric Violation
October 31, 2024
Nitrogen, ammonia total [as N]
29% over limit
Discharged 3.87 mg/L against a permitted limit of 3 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
September 30, 2024
BOD, carbonaceous [5 day, 20 C]
0% over limit
Discharged 0.00454 kg/d against a permitted limit of 14.982 kg/d (DAILY AV)
DMR, Limited - Overdue
Nitrogen, ammonia total [as N]
0% over limit
Discharged 0.00454 kg/d against a permitted limit of 4.53999996 kg/d (DAILY AV)
DMR, Limited - Overdue
pH
0% over limit
Discharged 7.3 SU against a permitted limit of 6 SU (MINIMUM)
DMR, Limited - Overdue
E. coli
0% over limit
Discharged 1 MPN/100mL against a permitted limit of 126 MPN/100mL (DAILY AV)
DMR, Limited - Overdue
pH
0% over limit
Discharged 8 SU against a permitted limit of 9 SU (MAXIMUM)
DMR, Limited - Overdue
Chlorine, total residual
0% over limit
Discharged 1.6 mg/L against a permitted limit of 1 mg/L (MO MIN)
DMR, Limited - Overdue
Flow, in conduit or thru treatment plant
0% over limit
Discharged 0.07 MGD against a permitted limit of 0.4 MGD (DAILY AV)
DMR, Limited - Overdue
Solids, total suspended
0% over limit
Discharged 8.4 mg/L against a permitted limit of 60 mg/L (SINGGRAB)
DMR, Limited - Overdue
Nitrogen, ammonia total [as N]
253% over limit
Discharged 10.58 mg/L against a permitted limit of 3 mg/L (DAILY AV)
DMR, Limited - Overdue
Nitrogen, ammonia total [as N]
253% over limit
Discharged 10.58 mg/L against a permitted limit of 3 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
0% over limit
Discharged 11.6 mg/L against a permitted limit of 35 mg/L (SINGGRAB)
DMR, Limited - Overdue
BOD, carbonaceous [5 day, 20 C]
0% over limit
Discharged 8.3 mg/L against a permitted limit of 10 mg/L (DAILY AV)
DMR, Limited - Overdue
Oxygen, dissolved [DO]
8% over limit
Discharged 4.6 mg/L against a permitted limit of 5 mg/L (MO MIN)
DMR, Limited - Overdue
Oxygen, dissolved [DO]
8% over limit
Discharged 4.6 mg/L against a permitted limit of 5 mg/L (MO MIN)
DMR, Limited - Numeric Violation
E. coli
0% over limit
Discharged 1 MPN/100mL against a permitted limit of 399 MPN/100mL (SINGGRAB)
DMR, Limited - Overdue
Solids, total suspended
0% over limit
Discharged 0.004086 kg/d against a permitted limit of 22.69999981 kg/d (DAILY AV)
DMR, Limited - Overdue
Nitrogen, ammonia total [as N]
25% over limit
Discharged 18.7 mg/L against a permitted limit of 15 mg/L (SINGGRAB)
DMR, Limited - Overdue
Nitrogen, ammonia total [as N]
25% over limit
Discharged 18.7 mg/L against a permitted limit of 15 mg/L (SINGGRAB)
DMR, Limited - Numeric Violation
Chlorine, total residual
0% over limit
Discharged 4 mg/L against a permitted limit of 4 mg/L (MO MAX)
DMR, Limited - Overdue
Flow, in conduit or thru treatment plant
0% over limit
Discharged 0.12 MGD against a permitted limit of 0 MGD (DAILY MX)
DMR, Monitor Only - Overdue
Solids, total suspended
0% over limit
Discharged 5.4 mg/L against a permitted limit of 15 mg/L (DAILY AV)
DMR, Limited - Overdue
August 31, 2024
BOD, carbonaceous [5 day, 20 C]
11% over limit
Discharged 39 mg/L against a permitted limit of 35 mg/L (SINGGRAB)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
649% over limit
Discharged 22.47 mg/L against a permitted limit of 3 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
14% over limit
Discharged 4.3 mg/L against a permitted limit of 5 mg/L (MO MIN)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
136% over limit
Discharged 35.4 mg/L against a permitted limit of 15 mg/L (SINGGRAB)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
66% over limit
Discharged 16.6 mg/L against a permitted limit of 10 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
July 31, 2024
BOD, carbonaceous [5 day, 20 C]
0% over limit
Discharged 21.8 mg/L against a permitted limit of 35 mg/L (SINGGRAB)
DMR, Limited - Overdue
Chlorine, total residual
0% over limit
Discharged 2.1 mg/L against a permitted limit of 4 mg/L (MO MAX)
DMR, Limited - Overdue
pH
0% over limit
Discharged 6.5 SU against a permitted limit of 6 SU (MINIMUM)
DMR, Limited - Overdue
E. coli
0% over limit
Discharged 16 MPN/100mL against a permitted limit of 126 MPN/100mL (DAILY AV)
DMR, Limited - Overdue
Nitrogen, ammonia total [as N]
5% over limit
Discharged 15.8 mg/L against a permitted limit of 15 mg/L (SINGGRAB)
DMR, Limited - Overdue
Nitrogen, ammonia total [as N]
5% over limit
Discharged 15.8 mg/L against a permitted limit of 15 mg/L (SINGGRAB)
DMR, Limited - Numeric Violation
pH
0% over limit
Discharged 7.5 SU against a permitted limit of 9 SU (MAXIMUM)
DMR, Limited - Overdue
Chlorine, total residual
0% over limit
Discharged 1.3 mg/L against a permitted limit of 1 mg/L (MO MIN)
DMR, Limited - Overdue
Oxygen, dissolved [DO]
8% over limit
Discharged 4.6 mg/L against a permitted limit of 5 mg/L (MO MIN)
DMR, Limited - Overdue
Oxygen, dissolved [DO]
8% over limit
Discharged 4.6 mg/L against a permitted limit of 5 mg/L (MO MIN)
DMR, Limited - Numeric Violation
E. coli
0% over limit
Discharged 16 MPN/100mL against a permitted limit of 399 MPN/100mL (SINGGRAB)
DMR, Limited - Overdue
Flow, in conduit or thru treatment plant
0% over limit
Discharged 1.07 MGD against a permitted limit of 0 MGD (DAILY MX)
DMR, Monitor Only - Overdue
Solids, total suspended
0% over limit
Discharged 0.00908 kg/d against a permitted limit of 22.69999981 kg/d (DAILY AV)
DMR, Limited - Overdue
BOD, carbonaceous [5 day, 20 C]
0% over limit
Discharged 0.01362 kg/d against a permitted limit of 14.982 kg/d (DAILY AV)
DMR, Limited - Overdue
Nitrogen, ammonia total [as N]
181% over limit
Discharged 8.43 mg/L against a permitted limit of 3 mg/L (DAILY AV)
DMR, Limited - Overdue
Nitrogen, ammonia total [as N]
181% over limit
Discharged 8.43 mg/L against a permitted limit of 3 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
8% over limit
Discharged 10.8 mg/L against a permitted limit of 10 mg/L (DAILY AV)
DMR, Limited - Overdue
BOD, carbonaceous [5 day, 20 C]
8% over limit
Discharged 10.8 mg/L against a permitted limit of 10 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
Flow, in conduit or thru treatment plant
0% over limit
Discharged 0.27 MGD against a permitted limit of 0.4 MGD (DAILY AV)
DMR, Limited - Overdue
Solids, total suspended
0% over limit
Discharged 6.3 mg/L against a permitted limit of 15 mg/L (DAILY AV)
DMR, Limited - Overdue
Nitrogen, ammonia total [as N]
0% over limit
Discharged 0.00908 kg/d against a permitted limit of 4.53999996 kg/d (DAILY AV)
DMR, Limited - Overdue
Solids, total suspended
0% over limit
Discharged 11.3 mg/L against a permitted limit of 60 mg/L (SINGGRAB)
DMR, Limited - Overdue
First flagged
April 14, 2026 (3 months ago)
Last confirmed
July 13, 2026 (23 days ago)