Clean Water Act discharge permit · NPDES ID0023981
BOISE, CITY OF - WEST BOISE WWTP, Boise, ID: NPDES ID0023981 discharge permit, effluent exceedances, inspections, penalties
- Administratively continuedPermit status
- MajorDischarger class
- 44Pollutants under a numeric limit
- 7Pollutants with an effluent exceedance
- 0Inspections on file
- 0Formal enforcement actions
BOISE, CITY OF - WEST BOISE WWTP, held by BOISE, CITY OF, holds NPDES permit ID0023981, which discharges to Boise River (River Mile 45.1). EPA’s file records it issued March 15, 2012 and expiring July 31, 2017. The status and dates are as EPA’s permit file stood when Velarion loaded it (October 14, 2026); EPA’s free Detailed Facility Report on ECHO carries the permit’s current standing.
Identity
| Facility as filed | BOISE, CITY OF - WEST BOISE WWTP |
|---|---|
| Permittee as filed | BOISE, CITY OF |
| NPDES ID | ID0023981 |
| Permit status | Administratively continued (past its expiration date and still in force until reissued) |
| Permit type | Individual permit |
| Discharger class | Major discharger |
| Facility type | Publicly owned treatment works |
| Program | Publicly owned treatment works |
| Issued | March 15, 2012 |
| Expiration date | July 31, 2017 |
| Address | Boise, ID 83714 |
| Receiving water | BOISE RIVER (RIVER MILE 45.1) |
| Receiving water impaired | 303(D) Listed |
| Subwatershed | North Slough-Boise River (HUC 170501140404) |
| Program components on file | POTW, Pretreatment |
| NAICS | 221320 – Sewage Treatment Facilities |
| SIC | 4952 – Sewerage Systems |
| Other EPA IDs (FRS) | RCRA handler IDR000206672 |
Cited to the EPA ICIS-NPDES permit file (ECHO download) and EPA’s NAICS/SIC and component files, the same download; cross-program IDs from EPA’s FRS facility-registry crosswalk.
Effluent limits and exceedances
- 54Pollutants on file
- 44Under a numeric limit
- 34With a violation of any kind
- 7With an effluent exceedance
An effluent exceedance is a discharge monitoring report value over the permit’s numeric limit (EPA’s violation code E90). A violation of any kind also counts a report not filed. Each row is EPA’s own count for that pollutant.
| Pollutant or measure | Limits | Violations, any kind | Effluent exceedances | Latest exceedance | Largest exceedance, as filed |
|---|---|---|---|---|---|
| Mercury, total recoverable | 6 | 57 | 19 | November 30, 2014 | 900% over the limit |
| Nitrogen, ammonia total [as N] | 9 | 74 | 14 | March 31, 2021 | 1,412% over the limit |
| Temperature, water deg. centigrade | 7 | 93 | 3 | March 31, 2026 | 5% over the limit |
| E. coli | 3 | 3 | 3 | October 31, 2020 | 3,595% over the limit |
| Toxicity, Chronic | 0 | 2 | 2 | September 30, 2025 | 41% over the limit |
| Solids, total suspended | 6 | 121 | 1 | July 31, 2011 | 6% over the limit |
| Oxygen, dissolved [DO] | 3 | 31 | 1 | January 31, 2009 | 99,999% over the limit |
| Phosphorus, total [as P] | 12 | 120 | 0 | ||
| BOD, 5-day, 20 deg. C | 6 | 120 | 0 | ||
| Alkalinity, total [as CaCO3] | 2 | 90 | 0 | ||
| pH | 10 | 60 | 0 | ||
| E. coli, MTEC-MF | 3 | 60 | 0 | ||
| Nitrogen, Kjeldahl, total [as N] | 2 | 60 | 0 | ||
| Nitrite + Nitrate total [as N] | 2 | 60 | 0 | ||
| Phosphate, ortho [as PO4] | 0 | 60 | 0 | ||
| Coliform, fecal MF, MFC broth, 44.5 C | 0 | 60 | 0 | ||
| Flow | 0 | 60 | 0 | ||
| Carbon, tot organic [TOC] | 3 | 52 | 0 | ||
| Hardness, total [as CaCO3] | 3 | 46 | 0 | ||
| Turbidity | 2 | 30 | 0 | ||
| Arsenic, total recoverable | 2 | 30 | 0 | ||
| Cadmium, dissolved [as Cd] | 2 | 30 | 0 | ||
| Copper, dissolved [as Cu] | 2 | 30 | 0 | ||
| Lead, dissolved [as Pb] | 2 | 30 | 0 | ||
| Silver, dissolved [as Ag] | 2 | 30 | 0 | ||
| Zinc, dissolved [as Zn] | 2 | 30 | 0 | ||
| Chromium, dissolved [as Cr] | 1 | 30 | 0 | ||
| Nickel, dissolved [as Ni] | 1 | 30 | 0 | ||
| Streamflow | 0 | 30 | 0 | ||
| Oil and grease, hexane extr method | 0 | 30 | 0 | ||
| IC25 Sub-Lethal Static Renewal 7 Day Chronic Ceriodaphnia dubia | 0 | 2 | 0 | ||
| IC25 Sub-Lethal Static Renewal 7 Day Chronic Pimephales promelas | 0 | 2 | 0 | ||
| NOEC Lethal Static Renewal 7 Day Chronic Ceriodaphnia dubia | 0 | 2 | 0 | ||
| NOEC Lethal Static Renewal 7 Day Chronic Pimephales promelas | 0 | 2 | 0 | ||
| Temperature, water deg. fahrenheit | 8 | 0 | 0 | ||
| Aluminum, total recoverable | 7 | 0 | 0 | ||
| Flow, in conduit or thru treatment plant | 7 | 0 | 0 | ||
| Iron, total recoverable | 3 | 0 | 0 | ||
| Cyanide, weak acid, dissociable | 2 | 0 | 0 | ||
| Selenium, total recoverable | 2 | 0 | 0 | ||
| Silver total recoverable | 2 | 0 | 0 | ||
| Zinc, total recoverable | 2 | 0 | 0 | ||
| Cadmium, total recoverable | 2 | 0 | 0 | ||
| Lead, total recoverable | 2 | 0 | 0 | ||
| Copper, total recoverable | 2 | 0 | 0 | ||
| Oil and grease | 2 | 0 | 0 | ||
| Toxicity [chronic], Ceriodaphnia dubia | 2 | 0 | 0 | ||
| Toxicity [chronic], Pimephales promelas [Fathead Minnow] | 2 | 0 | 0 | ||
| Nickel, total recoverable | 1 | 0 | 0 | ||
| Aluminum, dissolved [as Al] | 1 | 0 | 0 | ||
| Chromium, total recoverable | 1 | 0 | 0 | ||
| Aluminum | 1 | 0 | 0 | ||
| BOD, 5-day, percent removal | 1 | 0 | 0 | ||
| Solids, suspended percent removal | 1 | 0 | 0 |
Cited to the EPA ICIS-NPDES limits and effluent violations files (ECHO download); up to 60 rows shown, most exceedances first.
Inspections, violations and enforcement
- 4Single-event violations
| Date | What EPA recorded | Agency |
|---|---|---|
| July 23, 2026 | WW SSO - Overflow to Dry Land or Building Backup | ST6 |
| June 22, 2026 | WW SSO - Overflow to Dry Land or Building Backup | ST6 |
| April 6, 2026 | WW SSO - Overflow to Dry Land or Building Backup | ST6 |
| March 19, 2026 | WW SSO - Overflow to Dry Land or Building Backup | ST6 |
Inspections
EPA’s inspection file holds no inspection for NPDES ID0023981.
Formal enforcement and penalties
0 formal actions, 0 of them with a penalty assessed. Federal and state penalties are separate figures from separate authorities and are shown as each was filed, never added together.
Informal enforcement
| Date | What EPA recorded | Agency |
|---|---|---|
| July 28, 2026 | No Further Action | State |
Cited to the EPA ICIS-NPDES violation, inspection and enforcement files (ECHO download); up to 50 rows of each shown, newest first.
Watch this permit
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EPA publishes a free Detailed Facility Report for every permit on ECHO: its compliance status quarter by quarter, its inspections, and its enforcement actions and penalties. EPA also sends free notices of new inspections and enforcement actions through ECHO Notify; enter NPDES ID ID0023981 there.
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Figures from EPA’s ICIS-NPDES download, loaded October 14, 2026.