Clean Water Act discharge permit · NPDES MD0021741
WESTERN BRANCH WWTP, Upper Marlboro, MD: NPDES MD0021741 discharge permit, effluent exceedances, inspections, penalties
- Administratively continuedPermit status
- MajorDischarger class
- 17Pollutants under a numeric limit
- 10Pollutants with an effluent exceedance
WESTERN BRANCH WWTP, held by Washington Suburban Sanitary Commission - WSSC, holds NPDES permit MD0021741, which discharges to W.Br.Of Patuxent River. EPA’s file records it issued August 12, 2016 and expiring August 31, 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 | WESTERN BRANCH WWTP |
|---|---|
| Permittee as filed | Washington Suburban Sanitary Commission - WSSC |
| NPDES ID | MD0021741 |
| 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 | August 12, 2016 |
| Expiration date | August 31, 2021 |
| Issuing agency | MARYLAND DEPARTMENT OF THE ENVIORNMENT |
| Address | Upper Marlboro, MD 20772 |
| Receiving water | W.BR.OF PATUXENT RIVER |
| Subwatershed | Charles Branch-Western Branch Patuxent River (HUC 020600060304) |
| Program components on file | POTW, Pretreatment |
| SIC | 4952 – Sewerage Systems |
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
- 21Pollutants on file
- 17Under a numeric limit
- 20With a violation of any kind
- 10With 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 |
|---|---|---|---|---|---|
| Flow, in conduit or thru treatment plant | 2 | 39 | 36 | December 31, 2003 | 8,452% over the limit |
| Nitrogen, total [as N] | 11 | 39 | 22 | August 31, 2020 | 267% over the limit |
| BOD, 5-day, 20 deg. C | 8 | 24 | 7 | May 31, 2014 | 97% over the limit |
| E. coli | 1 | 8 | 7 | March 31, 2024 | 313% over the limit |
| Solids, total suspended | 10 | 39 | 6 | November 30, 2020 | 51% over the limit |
| Nitrogen, ammonia total [as N] | 4 | 8 | 6 | April 30, 2014 | 427% over the limit |
| pH | 2 | 5 | 3 | May 31, 2014 | |
| Enterococci | 0 | 4 | 3 | March 31, 2024 | 123% over the limit |
| Oxygen, dissolved [DO] | 5 | 9 | 2 | March 31, 2010 | 16% over the limit |
| Chlorine, total residual | 2 | 7 | 1 | December 31, 2005 | 100% over the limit |
| Phosphorus, total [as P] | 7 | 5 | 0 | ||
| Copper, total recoverable | 1 | 3 | 0 | ||
| Hardness, total [as CaCO3] | 2 | 2 | 0 | ||
| Phosphorous, in total orthophosphate | 2 | 2 | 0 | ||
| Flow, total | 2 | 2 | 0 | ||
| Nitrogen, organic total [as N] | 1 | 1 | 0 | ||
| Nitrite + Nitrate total [as N] | 1 | 1 | 0 | ||
| Nitrogen, Kjeldahl, total [as N] | 0 | 1 | 0 | ||
| BOD, 5-day, percent removal | 0 | 1 | 0 | ||
| Solids, suspended percent removal | 0 | 1 | 0 | ||
| Flow | 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
- 0Single-event violations
EPA’s single-event violation file, as loaded, holds no violation for NPDES MD0021741.
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 MD0021741 there.
Nearby on the register
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- Every permit record in Maryland, A to Z
Figures from EPA’s ICIS-NPDES download, loaded October 14, 2026.