Clean Water Act discharge permit · NPDES MA0100412
WESTBOROUGH W W T P, Westborough, MA: NPDES MA0100412 discharge permit, effluent exceedances, inspections, penalties
- Administratively continuedPermit status
- MajorDischarger class
- 19Pollutants under a numeric limit
- 16Pollutants with an effluent exceedance
WESTBOROUGH W W T P holds NPDES permit MA0100412, which discharges to Assabet River. EPA’s file records it issued May 2, 2005 and expiring October 31, 2010. The status and dates are as EPA’s permit file stood when Velarion loaded it (September 15, 2026); EPA’s free Detailed Facility Report on ECHO carries the permit’s current standing.
Identity
| Facility as filed | WESTBOROUGH W W T P |
|---|---|
| Permittee as filed | WESTBOROUGH W W T P |
| NPDES ID | MA0100412 |
| 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 | May 2, 2005 |
| Expiration date | October 31, 2010 |
| Address | Westborough, MA 01581 |
| Receiving water | ASSABET RIVER |
| Subwatershed | Headwaters Assabet River (HUC 010700050201) |
| Other EPA IDs (FRS) | RCRA handler MAR000525253 |
Cited to the EPA ICIS-NPDES permit file (ECHO download); cross-program IDs from EPA’s FRS facility-registry crosswalk.
Effluent limits and exceedances
- 30Pollutants on file
- 19Under a numeric limit
- 29With a violation of any kind
- 16With 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 |
|---|---|---|---|---|---|
| pH | 2 | 87 | 82 | March 31, 2015 | |
| Copper, total [as Cu] | 8 | 139 | 63 | April 30, 2022 | 142% over the limit |
| Phosphorus, total [as P] | 24 | 27 | 16 | January 31, 2023 | 459,900% over the limit |
| NOEL Static Renewal 7Day Chronic Ceriodaphnia dubia | 1 | 13 | 12 | March 31, 2014 | 94% over the limit |
| Solids, total suspended | 12 | 22 | 9 | July 31, 2025 | 216% over the limit |
| Nitrogen, ammonia total [as N] | 7 | 15 | 6 | July 31, 2011 | 453% over the limit |
| Flow, in conduit or thru treatment plant | 3 | 14 | 6 | October 31, 2005 | 13% over the limit |
| Chlorine, total residual | 2 | 21 | 3 | September 30, 2010 | 1,625% over the limit |
| BOD, carbonaceous [5 day, 20 C] | 6 | 7 | 3 | February 29, 2008 | 108% over the limit |
| Coliform, fecal general | 2 | 4 | 2 | March 31, 2008 | 150% over the limit |
| Solids, suspended percent removal | 1 | 4 | 2 | March 31, 2008 | 40% over the limit |
| E. coli | 0 | 4 | 2 | July 31, 2024 | 156% over the limit |
| BOD, 5-day, 20 deg. C | 7 | 14 | 1 | April 30, 2016 | 20% over the limit |
| BOD, 5-day, percent removal | 1 | 4 | 1 | March 31, 2008 | 7% over the limit |
| LC50 Static 48Hr Acute Ceriodaphnia dubia | 1 | 3 | 1 | June 30, 2002 | 29% over the limit |
| NOEL Static 7Day Chronic Ceriodaphnia dubia | 0 | 2 | 1 | September 30, 2022 | 50% over the limit |
| Lead, total [as Pb] | 2 | 5 | 0 | ||
| Zinc, total [as Zn] | 2 | 4 | 0 | ||
| Aluminum, total [as Al] | 2 | 4 | 0 | ||
| Oxygen, dissolved [DO] | 1 | 3 | 0 | ||
| Nitrogen, total [as N] | 0 | 2 | 0 | ||
| Nitrogen, Kjeldahl, total [as N] | 0 | 2 | 0 | ||
| Nitrite + Nitrate total [as N] | 0 | 2 | 0 | ||
| Carbon, tot organic [TOC] | 0 | 2 | 0 | ||
| Hardness, total [as CaCO3] | 0 | 2 | 0 | ||
| Cadmium, total [as Cd] | 0 | 2 | 0 | ||
| Nickel, total [as Ni] | 0 | 2 | 0 | ||
| Temperature, water deg. centigrade | 0 | 1 | 0 | ||
| Carbon, dissolved organic [as C] | 0 | 1 | 0 | ||
| Phosphate, ortho, dissolved [as P] | 4 | 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
- 0Single-event violations
EPA’s single-event violation file, as loaded, holds no violation for NPDES MA0100412.
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 MA0100412 there.
Nearby on the register
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- Every permit record in Massachusetts, A to Z
Figures from EPA’s ICIS-NPDES download, loaded September 15, 2026.