LOWER MONUMENTAL LOCK AND DAM - USACE
NPDES ID: WA0026808
D — SNC: Discharge monitoring report not received
The facility didn't submit its required discharge monitoring report.
Violations
December 31, 2025
Suspended solids, total discharge
0% over limit
Discharged 0 mg/L against a permitted limit of 0 mg/L (QRTR AVG)
DMR, Monitor Only - Overdue
Suspended solids, total discharge
0% over limit
Discharged 0 mg/L against a permitted limit of 0 mg/L (QRTR AVG)
DMR, Monitor Only - Overdue
Oil & Grease
0% over limit
Discharged 0 mg/L against a permitted limit of 5 mg/L (DAILY MX)
DMR, Limited - Overdue
November 30, 2025
Oil & Grease
8% over limit
Discharged 5.4 mg/L against a permitted limit of 5 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
October 31, 2025
pH
0% over limit
Discharged 0 SU against a permitted limit of 8.5 SU (INST MAX)
DMR, Limited - Overdue
pH
0% over limit
Discharged 0 SU against a permitted limit of 6.5 SU (INST MIN)
DMR, Limited - Overdue
Oil & Grease
0% over limit
Discharged 0 mg/L against a permitted limit of 5 mg/L (DAILY MX)
DMR, Limited - Overdue
Oil & Grease
0% over limit
Discharged 0 mg/L against a permitted limit of 5 mg/L (DAILY MX)
DMR, Limited - Overdue
Temperature, water deg. centigrade
0% over limit
Discharged 0 deg C against a permitted limit of 0 deg C (MO MAX)
DMR, Monitor Only - Overdue
Oil & Grease
0% over limit
Discharged 0 mg/L against a permitted limit of 5 mg/L (DAILY MX)
DMR, Limited - Overdue
pH
0% over limit
Discharged 0 SU against a permitted limit of 8.5 SU (INST MAX)
DMR, Limited - Overdue
Temperature, water deg. centigrade
0% over limit
Discharged 0 deg C against a permitted limit of 0 deg C (MO AVG)
DMR, Monitor Only - Overdue
pH
0% over limit
Discharged 0 SU against a permitted limit of 6.5 SU (INST MIN)
DMR, Limited - Overdue
Oil & Grease
36% over limit
Discharged 6.8 mg/L against a permitted limit of 5 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Temperature, water deg. centigrade
0% over limit
Discharged 0 deg C against a permitted limit of 0 deg C (MX DA AV)
DMR, Monitor Only - Overdue
Temperature, water deg. centigrade
0% over limit
Discharged 0 deg C against a permitted limit of 0 deg C (MO AVG)
DMR, Monitor Only - Overdue
Flow, in conduit or thru treatment plant
0% over limit
Discharged 0 MGD against a permitted limit of 0 MGD (MO AVG)
DMR, Monitor Only - Overdue
Temperature, water deg. centigrade
0% over limit
Discharged 0 deg C against a permitted limit of 0 deg C (MX DA AV)
DMR, Monitor Only - Overdue
Temperature, water deg. centigrade
0% over limit
Discharged 0 deg C against a permitted limit of 0 deg C (MX 7D AV)
DMR, Monitor Only - Overdue
Temperature, water deg. centigrade
0% over limit
Discharged 0 deg C against a permitted limit of 0 deg C (MO MAX)
DMR, Monitor Only - Overdue
Temperature, water deg. centigrade
0% over limit
Discharged 0 deg C against a permitted limit of 0 deg C (7 DA MAX)
DMR, Monitor Only - Overdue
August 31, 2025
Oil & Grease
0% over limit
Discharged 0 mg/L against a permitted limit of 5 mg/L (DAILY MX)
DMR, Limited - Overdue
July 31, 2025
Oil & Grease
0% over limit
Discharged 0 mg/L against a permitted limit of 5 mg/L (DAILY MX)
DMR, Limited - Overdue
Oil & Grease
0% over limit
Discharged 0 mg/L against a permitted limit of 5 mg/L (DAILY MX)
DMR, Limited - Overdue
Oil & Grease
0% over limit
Discharged 0 mg/L against a permitted limit of 5 mg/L (DAILY MX)
DMR, Limited - Overdue
Oil & Grease
0% over limit
Discharged 0 mg/L against a permitted limit of 5 mg/L (DAILY MX)
DMR, Limited - Overdue
Oil & Grease
0% over limit
Discharged 0 mg/L against a permitted limit of 5 mg/L (DAILY MX)
DMR, Limited - Overdue
Oil & Grease
0% over limit
Discharged 0 mg/L against a permitted limit of 5 mg/L (DAILY MX)
DMR, Limited - Overdue
April 30, 2025
Oil & Grease
0% over limit
Discharged 0 mg/L against a permitted limit of 5 mg/L (DAILY MX)
DMR, Limited - Overdue
Oil & Grease
0% over limit
Discharged 0 mg/L against a permitted limit of 5 mg/L (DAILY MX)
DMR, Limited - Overdue
Oil & Grease
0% over limit
Discharged 0 mg/L against a permitted limit of 5 mg/L (DAILY MX)
DMR, Limited - Overdue
Oil & Grease
0% over limit
Discharged 0 mg/L against a permitted limit of 5 mg/L (DAILY MX)
DMR, Limited - Overdue
Oil & Grease
0% over limit
Discharged 0 mg/L against a permitted limit of 5 mg/L (DAILY MX)
DMR, Limited - Overdue
January 31, 2025
Oil & Grease
0% over limit
Discharged 0 mg/L against a permitted limit of 5 mg/L (DAILY MX)
DMR, Limited - Overdue
Oil & Grease
0% over limit
Discharged 0 mg/L against a permitted limit of 5 mg/L (DAILY MX)
DMR, Limited - Overdue
September 30, 2024
Oil & Grease
0% over limit
Discharged 3.99 mg/L against a permitted limit of 5 mg/L (DAILY MX)
DMR, Limited - Overdue
First flagged
April 14, 2026 (3 months ago)
Last confirmed
July 13, 2026 (23 days ago)