Clean Water Act discharge permit · NPDES CT0100463
PLYMOUTH WPCF, Pequabuck, CT: NPDES CT0100463 discharge permit, effluent exceedances, inspections, penalties
- Administratively continuedPermit status
- MajorDischarger class
- 27Pollutants under a numeric limit
- 14Pollutants with an effluent exceedance
PLYMOUTH WPCF holds NPDES permit CT0100463, which discharges to Pequabuck River. EPA’s file records it issued February 1, 2006 and expiring January 31, 2011. The status and dates are as EPA’s permit file stood when Velarion loaded it (September 14, 2026); EPA’s free Detailed Facility Report on ECHO carries the permit’s current standing.
Identity
| Facility as filed | PLYMOUTH WPCF |
|---|---|
| Permittee as filed | PLYMOUTH WPCF |
| NPDES ID | CT0100463 |
| 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 | February 1, 2006 |
| Expiration date | January 31, 2011 |
| Issuing agency | CT DEP |
| Address | Pequabuck, CT 06781 |
| Receiving water | PEQUABUCK RIVER |
| Receiving water impaired | 303(D) Listed |
| Subwatershed | Pequabuck River (HUC 010802070404) |
Cited to the EPA ICIS-NPDES permit file (ECHO download).
Effluent limits and exceedances
- 32Pollutants on file
- 27Under a numeric limit
- 17With a violation of any kind
- 14With 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 [as Zn] | 4 | 68 | 68 | January 31, 2025 | 243% over the limit |
| Copper, total [as Cu] | 4 | 25 | 25 | December 31, 2024 | 433% over the limit |
| pH | 2 | 24 | 24 | October 31, 2025 | |
| Solids, total suspended | 5 | 22 | 22 | May 31, 2021 | 578% over the limit |
| Coliform, fecal general | 2 | 19 | 19 | October 31, 2016 | 99,999% over the limit |
| Oxygen, dissolved [DO] | 1 | 12 | 12 | October 31, 2017 | 70% over the limit |
| Solids, suspended percent removal | 1 | 12 | 12 | July 31, 2021 | 133% over the limit |
| Phosphorus, total [as P] | 0 | 11 | 10 | October 31, 2021 | 59% over the limit |
| BOD, 5-day, percent removal | 1 | 8 | 8 | February 29, 2020 | 87% over the limit |
| Nitrogen, ammonia total [as N] | 14 | 3 | 3 | October 31, 2007 | 1,840% over the limit |
| Ultraviolet light intensity | 0 | 3 | 3 | May 31, 2025 | 100% over the limit |
| E. coli | 0 | 4 | 2 | June 30, 2018 | 99,999% over the limit |
| BOD, 5-day, 20 deg. C | 5 | 3 | 2 | January 31, 2019 | 452% over the limit |
| Flow, in conduit or thru treatment plant | 1 | 2 | 2 | March 31, 2011 | 9% over the limit |
| Polychlorinated biphenyls [PCBs] | 1 | 1 | 0 | ||
| Mercury, total [as Hg] | 0 | 1 | 0 | ||
| NOAEL Static 48Hr Acute Pimephales promelas | 0 | 1 | 0 | ||
| Pass/Fail Static 48Hr Acute D. Pulex | 2 | 0 | 0 | ||
| LC50 Static 48Hr Acute Pimephales promelas | 2 | 0 | 0 | ||
| Nitrogen, total [as N] | 1 | 0 | 0 | ||
| Arsenic, sludge tot. dry wt [as As] | 1 | 0 | 0 | ||
| Beryllium, sludge, tot. dry wt [as Be] | 1 | 0 | 0 | ||
| Solids, total, percent | 1 | 0 | 0 | ||
| Solids, fixed, % of total solids | 1 | 0 | 0 | ||
| Solids, volatile % of total solids | 1 | 0 | 0 | ||
| Zinc, sludge, total, dry weight [as Zn] | 1 | 0 | 0 | ||
| Lead, sludge, total, dry weight [as Pb] | 1 | 0 | 0 | ||
| Nickel, sludge, total, dry weight [as Ni] | 1 | 0 | 0 | ||
| Mercury, sludge, total, dry weight [as Hg] | 1 | 0 | 0 | ||
| Chromium, sludge, total, dry weight [as Cr] | 1 | 0 | 0 | ||
| Copper, sludge, total, dry weight [as Cu] | 1 | 0 | 0 | ||
| Cadmium, sludge, total, dry weight [as Cd] | 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
- 2Single-event violations
| Date | What EPA recorded | Agency |
|---|---|---|
| September 13, 2024 | Monitoring Violations - Analysis not Conducted | ST6 |
| November 29, 2021 | 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.
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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 CT0100463 there.
Nearby on the register
Figures from EPA’s ICIS-NPDES download, loaded September 14, 2026.