BOISE, CITY OF - WEST BOISE WWTP
NPDES ID: ID0023981
E — SNC: Effluent violation (monthly average limit)
The facility discharged more of a pollutant than its permit allows, based on a monthly average.
Violations
March 31, 2026
Temperature, water deg. centigrade
5% over limit
Discharged 18 deg C against a permitted limit of 17.1 deg C (DAILY MX)
DMR, Limited - Numeric Violation
November 30, 2025
Mercury, total recoverable
0% over limit
Discharged 0.00000554 mg/L against a permitted limit of 0 mg/L (DAILY MX)
DMR, Monitor Only - Overdue
Mercury, total recoverable
0% over limit
Discharged 0.00000229 mg/L against a permitted limit of 0 mg/L (MO AVG)
DMR, Monitor Only - Overdue
September 30, 2025
Toxicity, Chronic
41% over limit
Discharged 3.375 toxic against a permitted limit of 2.4 toxic (MO AVG)
DMR, Limited - Numeric Violation
Toxicity, Chronic
37% over limit
Discharged 5.75 toxic against a permitted limit of 4.2 toxic (DAILY MX)
DMR, Limited - Numeric Violation
Mercury, total recoverable
0% over limit
Discharged 0.00000238 mg/L against a permitted limit of 0 mg/L (MO AVG)
DMR, Monitor Only - Overdue
Mercury, total recoverable
0% over limit
Discharged 0.00000427 mg/L against a permitted limit of 0 mg/L (DAILY MX)
DMR, Monitor Only - Overdue
October 31, 2024
Mercury, total recoverable
0% over limit
Discharged 0.00000259 mg/L against a permitted limit of 0 mg/L (MO AVG)
DMR, Monitor Only - Overdue
Mercury, total recoverable
0% over limit
Discharged 0.00000474 mg/L against a permitted limit of 0 mg/L (DAILY MX)
DMR, Monitor Only - Overdue
First flagged
April 14, 2026 (3 months ago)
Last confirmed
July 13, 2026 (23 days ago)