SIERRA BLANCA
NPDES ID: TX0115657
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
April 30, 2026
BOD, 5-day, 20 deg. C
9% over limit
Discharged 109 mg/L against a permitted limit of 100 mg/L (SINGGRAB)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
106% over limit
Discharged 61.92 mg/L against a permitted limit of 30 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
pH
0% over limit
Discharged 9.23 SU against a permitted limit of 9 SU (MAXIMUM)
DMR, Limited - Numeric Violation
March 31, 2026
pH
0% over limit
Discharged 9.2 SU against a permitted limit of 9 SU (MAXIMUM)
DMR, Limited - Numeric Violation
E. coli
47% over limit
Discharged 185 MPN/100mL against a permitted limit of 126 MPN/100mL (DAILY AV)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
11% over limit
Discharged 33.2 mg/L against a permitted limit of 30 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
February 28, 2026
BOD, 5-day, 20 deg. C
69% over limit
Discharged 50.68 mg/L against a permitted limit of 30 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
pH
0% over limit
Discharged 9.27 SU against a permitted limit of 9 SU (MAXIMUM)
DMR, Limited - Numeric Violation
E. coli
395% over limit
Discharged 624 MPN/100mL against a permitted limit of 126 MPN/100mL (DAILY AV)
DMR, Limited - Numeric Violation
January 31, 2026
BOD, 5-day, 20 deg. C
98% over limit
Discharged 59.3 mg/L against a permitted limit of 30 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
E. coli
45% over limit
Discharged 183 MPN/100mL against a permitted limit of 126 MPN/100mL (DAILY AV)
DMR, Limited - Numeric Violation
December 31, 2025
BOD, 5-day, 20 deg. C
0% over limit
Discharged 88.3 mg/L against a permitted limit of 100 mg/L (SINGGRAB)
DMR, Limited - Overdue
BOD, 5-day, 20 deg. C
61% over limit
Discharged 48.2 mg/L against a permitted limit of 30 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
Solids, total suspended
13% over limit
Discharged 102.14 mg/L against a permitted limit of 90 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
0% over limit
Discharged 7.23 mg/L against a permitted limit of 4 mg/L (MO MIN)
DMR, Limited - Overdue
E. coli
0% over limit
Discharged 280 MPN/100mL against a permitted limit of 399 MPN/100mL (SINGGRAB)
DMR, Limited - Overdue
pH
0% over limit
Discharged 9.52 SU against a permitted limit of 9 SU (MAXIMUM)
DMR, Limited - Numeric Violation
November 30, 2025
BOD, 5-day, 20 deg. C
112% over limit
Discharged 63.52 mg/L against a permitted limit of 30 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
27% over limit
Discharged 127 mg/L against a permitted limit of 100 mg/L (SINGGRAB)
DMR, Limited - Numeric Violation
October 31, 2025
E. coli
Limit violation
Discharged 2400 MPN/100mL against a permitted limit of 399 MPN/100mL (SINGGRAB)
DMR, Limited - Numeric Violation
E. coli
75% over limit
Discharged 220 MPN/100mL against a permitted limit of 126 MPN/100mL (DAILY AV)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
23% over limit
Discharged 123 mg/L against a permitted limit of 100 mg/L (SINGGRAB)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
187% over limit
Discharged 86.16 mg/L against a permitted limit of 30 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
9% over limit
Discharged 3.63 mg/L against a permitted limit of 4 mg/L (MO MIN)
DMR, Limited - Numeric Violation
Solids, total suspended
9% over limit
Discharged 97.72 mg/L against a permitted limit of 90 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
September 30, 2025
Oxygen, dissolved [DO]
73% over limit
Discharged 1.08 mg/L against a permitted limit of 4 mg/L (MO MIN)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
67% over limit
Discharged 50.1 mg/L against a permitted limit of 30 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
August 31, 2025
Oxygen, dissolved [DO]
69% over limit
Discharged 1.24 mg/L against a permitted limit of 4 mg/L (MO MIN)
DMR, Limited - Numeric Violation
E. coli
73% over limit
Discharged 690 MPN/100mL against a permitted limit of 399 MPN/100mL (SINGGRAB)
DMR, Limited - Numeric Violation
E. coli
43% over limit
Discharged 180 MPN/100mL against a permitted limit of 126 MPN/100mL (DAILY AV)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
106% over limit
Discharged 61.65 mg/L against a permitted limit of 30 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
July 31, 2025
Solids, total suspended
33% over limit
Discharged 120 mg/L against a permitted limit of 90 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
54% over limit
Discharged 154 mg/L against a permitted limit of 100 mg/L (SINGGRAB)
DMR, Limited - Numeric Violation
E. coli
502% over limit
Discharged 2400 MPN/100mL against a permitted limit of 399 MPN/100mL (SINGGRAB)
DMR, Limited - Numeric Violation
E. coli
477% over limit
Discharged 727 MPN/100mL against a permitted limit of 126 MPN/100mL (DAILY AV)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
269% over limit
Discharged 110.72 mg/L against a permitted limit of 30 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
June 30, 2025
BOD, 5-day, 20 deg. C
104% over limit
Discharged 61.27 mg/L against a permitted limit of 30 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
75% over limit
Discharged 1.01 mg/L against a permitted limit of 4 mg/L (MO MIN)
DMR, Limited - Numeric Violation
E. coli
2% over limit
Discharged 129 MPN/100mL against a permitted limit of 126 MPN/100mL (DAILY AV)
DMR, Limited - Numeric Violation
Solids, total suspended
49% over limit
Discharged 134 mg/L against a permitted limit of 90 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
May 31, 2025
BOD, 5-day, 20 deg. C
55% over limit
Discharged 46.42 mg/L against a permitted limit of 30 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
April 30, 2025
E. coli
502% over limit
Discharged 2400 MPN/100mL against a permitted limit of 399 MPN/100mL (SINGGRAB)
DMR, Limited - Numeric Violation
E. coli
687% over limit
Discharged 992 MPN/100mL against a permitted limit of 126 MPN/100mL (DAILY AV)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
66% over limit
Discharged 49.76 mg/L against a permitted limit of 30 mg/L (DAILY AV)
DMR, Limited - Numeric Violation
First flagged
April 14, 2026 (3 months ago)
Last confirmed
July 13, 2026 (23 days ago)