Patapsco Wastewater Treatment Plant
3501 Asiatic Avenue, Baltimore, MD 21226 · Baltimore City County · Publicly Owned Treatment Works
- Average flow
- 51.59 MGD
- Design flow
- —
- NPDES permit
- MDL021601
- Effective
- Permit expires
- December 2030
- Population served
- 293,367
- CWNS 2022
Patapsco Wastewater Treatment Plant is a publicly owned wastewater treatment works in Baltimore, Baltimore City County, Maryland treating an average of 51.59 million gallons per day, serving about 293,367 residents. It discharges under NPDES permit MDL021601 (effective), which expires in December 2030, with 22 recorded violations in the last three years. EPA has recorded 7 formal enforcement actions naming the plant, the latest in January 2024.
Treatment technology
3 treatment structures and unit processes identified at Patapsco Wastewater Treatment Plant.
Available with a free Klarifi account
See the full treatment train at Patapsco Wastewater Treatment Plant: structures, unit processes and planned upgrades, with exact unit counts.
Compliance snapshot (last 3 years)
- Total violations
- 22
- Effluent violations
- 10
Based on NPDES Discharge Monitoring Reports. Full violation history, parameters and discharge data available in the Klarifi platform.
EPA enforcement history
Federal civil enforcement cases, compliance inspections and informal actions recorded for Patapsco Wastewater Treatment Plant in EPA's ICIS system.
- Formal actions
- 7
- 2 since FY2020
- Penalties assessed
- $1.1M
- all cases
- Compliance actions
- $2,723M
- required by EPA orders
- EPA inspections
- 3
- latest Jun 2025
Latest case · Jan 2024
BALTIMORE, CITY OF
Administrative order · SDWA, National Drinking Water Regulations · Final Order No Penalty · Compliance actions $197,633
EPA's description of the case:
“On July 20, 2023, Region III and the City of Baltimore agreed to an Administrative Order on Consent requiring the City to complete work on two of the City's finished water reservoirs, Druid Lake and…”
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Source: EPA ECHO, civil enforcement case 03-2023-0124.
Full case history with a free Klarifi account
Every action against Patapsco Wastewater Treatment Plant with dates, milestones, violation types and EPA's complete case summaries, plus inspections and informal actions.
Capital improvement projects in Baltimore
Baltimore's capital improvement plan lists 212 water, sewer and wastewater line items worth $4.7B starting 2025–2031. The largest budgeted items are shown here.
All water and sewer capital projects in Baltimore →
| Project | Budget | Years |
|---|---|---|
| Future Water Main Replacement | $280,000,000 | 2027–2031 |
| Baltimore St./Smallwood St./Reisterstown Rd. Area Water Main Replacements | $199,868,000 | 2026–2030 |
| OF Hyd Outfall Phase II Sewershed Improvements for 5 Year Storm LOP | $155,083,680 | 2027–2029 |
| (Project 1355) Activated Plant 3 Rehab at BRWWTP | $122,148,822 | 2027–2027 |
| Construction Reserve Meter Replacement | $110,000,000 | 2026–2031 |
Full project details — scope, funding source, engineering consultant and the decision-makers behind each project — are available in Klarifi, along with similar wastewater capital projects in other cities.
Key contacts
12 verified contacts for Patapsco Wastewater Treatment Plant, with validated emails and direct phone numbers.
Unlock 12 verified contacts (9 more than shown)
Names, validated emails and direct phone numbers for decision-makers at Patapsco Wastewater Treatment Plant, plus the full compliance history and discharge data.
Nearby wastewater treatment plants in Maryland
Baltimore · 6 mi away
107.68 MGD
Odenton · 15 mi away
0.47 MGD
Perry Hall · 15 mi away
0.02 MGD
Savage · 15 mi away
16.76 MGD
Glen Arm · 16 mi away
—
Annapolis · 17 mi away
3.79 MGD
Laurel · 17 mi away
1.49 MGD
Bowie · 18 mi away
5.09 MGD
Patapsco Wastewater Treatment Plant: frequently asked questions
Sources and methodology
Flow, permit and violation figures come from the EPA's ICIS-NPDES discharge monitoring records. Population served comes from the Clean Watersheds Needs Survey 2022. Treatment structures are identified by Klarifi's review of aerial imagery, and capital improvement projects are extracted from published municipal budget documents. Violations are counted over the last three years of monitoring reports.
Data refreshed October 26, 2026; facility record last updated September 2, 2025.
Wastewater terms: POTW · MGD · NPDES permit · Inflow and infiltration · Anaerobic digester · Lift station · all terms