Clean Water Act discharge permit · NPDES MT0022390
LIBBY DAM WWTP, Libby, MT: NPDES MT0022390 discharge permit, effluent exceedances, inspections, penalties
- Administratively continuedPermit status
- MinorDischarger class
- 15Pollutants under a numeric limit
- 5Pollutants with an effluent exceedance
LIBBY DAM WWTP, held by USCOE LIBBY DAM, holds NPDES permit MT0022390, which discharges to Kootenai River. EPA’s file records it issued May 14, 2015 and expiring June 30, 2020. 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 | LIBBY DAM WWTP |
|---|---|
| Permittee as filed | USCOE LIBBY DAM |
| NPDES ID | MT0022390 |
| Permit status | Administratively continued (past its expiration date and still in force until reissued) |
| Permit type | Individual permit |
| Discharger class | Minor discharger |
| Facility type | Federal facility |
| Issued | May 14, 2015 |
| Expiration date | June 30, 2020 |
| Issuing agency | MONTANA DEQ |
| Address | Libby, MT 59923 |
| Receiving water | KOOTENAI RIVER |
| Receiving water impaired | 303(D) Listed |
| Subwatershed | Upper Kootenai River (HUC 170101010711) |
| SIC | 1623 – Water, Sewer, And Utility Lines |
| Other EPA IDs (FRS) | RCRA handler MTR000004747 |
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
- 17Pollutants on file
- 15Under a numeric limit
- 17With a violation of any kind
- 5With 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 |
|---|---|---|---|---|---|
| E. coli, MTEC-MF | 4 | 26 | 18 | September 30, 2013 | 688% over the limit |
| Solids, total suspended | 6 | 29 | 10 | June 30, 2013 | 318% over the limit |
| Chlorine, total residual | 0 | 4 | 4 | April 30, 2012 | 880% over the limit |
| pH | 5 | 19 | 2 | August 31, 2012 | |
| BOD, 5-day, 20 deg. C | 6 | 20 | 1 | May 31, 2012 | 113% over the limit |
| Temperature, water deg. fahrenheit | 18 | 51 | 0 | ||
| Flow rate | 15 | 42 | 0 | ||
| Oil and grease, hexane extr method | 7 | 24 | 0 | ||
| Nitrogen, total [as N] | 2 | 10 | 0 | ||
| Phosphorus, total [as P] | 2 | 10 | 0 | ||
| Nitrogen, ammonia total [as N] | 1 | 5 | 0 | ||
| Nitrite + Nitrate total [as N] | 1 | 5 | 0 | ||
| Nitrogen, Kjeldahl, total [as N] | 1 | 4 | 0 | ||
| BOD, 5-day, percent removal | 1 | 4 | 0 | ||
| Solids, suspended percent removal | 1 | 4 | 0 | ||
| Temperature, water deg. centigrade | 0 | 3 | 0 | ||
| Solids, total dissolved [TDS] | 1 | 2 | 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
- 3Single-event violations
| Date | What EPA recorded | Agency |
|---|---|---|
| March 13, 2025 | Monitoring Violations - Analysis not Conducted | ST6 |
| March 13, 2025 | Monitoring Violations - Frequency of Sampling Violation | ST6 |
| March 13, 2025 | Monitoring Violations - Invalid/Unrepresentative Sample | ST6 |
Velarion’s copy of EPA’s ICIS-NPDES files does not include the inspections, formal enforcement actions and informal enforcement actions files, so this page shows none of them. EPA’s free Detailed Facility Report on ECHO lists this permit’s inspections, enforcement actions and penalties.
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
One permit holder, $99/month. Watch the register for one permit holder and the places and receiving waters tied to its permits. Choose “One permit holder” and enter this permit’s NPDES ID, MT0022390.
Start the watch
- One permit holder — $99/month
- One watershed — $2,990/year
- One state — $4,990/year
- The whole register — $18,000/year
How we handle your data → Privacy
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 MT0022390 there.
Nearby on the register
- Discharge permits in Libby
- Every permit record in Libby, A to Z
- Discharge permits in Montana
- Every permit record in Montana, A to Z
Figures from EPA’s ICIS-NPDES download, loaded October 14, 2026.