Clean Water Act discharge permit · NPDES MT0028720
TENMILE WATER TREATMENT PLANT, Helena, MT: NPDES MT0028720 discharge permit, effluent exceedances, inspections, penalties
- Administratively continuedPermit status
- MinorDischarger class
- 11Pollutants under a numeric limit
- 7Pollutants with an effluent exceedance
TENMILE WATER TREATMENT PLANT, held by CITY OF HELENA, holds NPDES permit MT0028720, which discharges to Ten Mile Creek. EPA’s file records it issued October 11, 2016 and expiring November 30, 2021. 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 | TENMILE WATER TREATMENT PLANT |
|---|---|
| Permittee as filed | CITY OF HELENA |
| NPDES ID | MT0028720 |
| Permit status | Administratively continued (past its expiration date and still in force until reissued) |
| Permit type | Individual permit |
| Discharger class | Minor discharger |
| Facility type | Publicly owned treatment works |
| Program | Publicly owned treatment works |
| Issued | October 11, 2016 |
| Expiration date | November 30, 2021 |
| Address | Helena, MT 59601 |
| Receiving water | TEN MILE CREEK |
| Subwatershed | Middle Tenmile Creek (HUC 100301011402) |
| SIC | 4941 – Water Supply |
Cited to the EPA ICIS-NPDES permit file (ECHO download) and EPA’s NAICS/SIC and component files, the same download.
Effluent limits and exceedances
- 14Pollutants on file
- 11Under a numeric limit
- 14With 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 |
|---|---|---|---|---|---|
| Zinc, total recoverable | 2 | 103 | 81 | May 31, 2023 | 415% over the limit |
| Cadmium, total recoverable | 2 | 97 | 75 | June 30, 2023 | 21,329% over the limit |
| Aluminum, dissolved [as Al] | 2 | 32 | 10 | December 31, 2014 | 1,015% over the limit |
| Solids, total suspended | 3 | 35 | 2 | June 30, 2022 | 44% over the limit |
| Copper, total recoverable | 4 | 24 | 2 | January 31, 2007 | 278% over the limit |
| Chlorine, total residual | 2 | 25 | 1 | May 31, 2016 | 30% over the limit |
| Flow rate | 0 | 1 | 1 | January 31, 2007 | 49% over the limit |
| Flow rate | 3 | 33 | 0 | ||
| pH | 2 | 22 | 0 | ||
| Arsenic, total recoverable | 2 | 22 | 0 | ||
| Duration | 1 | 11 | 0 | ||
| E. coli, MTEC-MF | 0 | 4 | 0 | ||
| Solids, total dissolved [TDS] | 0 | 4 | 0 | ||
| Nitrogen, total [as N] | 1 | 3 | 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
- 7Single-event violations
| Date | What EPA recorded | Agency |
|---|---|---|
| March 14, 2023 | Monitoring Violations - Frequency of Sampling Violation | ST6 |
| March 14, 2023 | Monitoring Violations - Invalid/Unrepresentative Sample | ST6 |
| March 14, 2023 | Reporting Violations - Improper/ Incorrect Reporting | ST6 |
| March 14, 2023 | Monitoring Violations - Improper Analysis or Lab Error | ST6 |
| March 15, 2019 | Management Practice Violations - Failure to Maintain Records | ST6 |
| March 15, 2019 | Monitoring Violations - Improper Analysis or Lab Error | ST6 |
| March 15, 2019 | Reporting Violations - Failure to submit required report (non-DMR non-pretreatment) | 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, MT0028720.
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 MT0028720 there.
Nearby on the register
- Discharge permits in Helena
- Every permit record in Helena, 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.