EPA system MD0300002 · Maryland
City of Baltimore: 1 PFAS found; PFPeA up to 3.0 ppt, no EPA limit set
90th percentile for the latest monitoring period; sampled Dec 31, 2024. Source: EPA SDWIS/ECHO.
City of Baltimore is a local-government-owned community water system in Maryland serving about 1,600,000 people, matched to 63 ZIP codes.
MCL 4.0 ppt · not detected above the reporting level
MCL 4.0 ppt · not detected above the reporting level
health reference level 10 ppb · not detected above the reporting level
PFAS and lithium: what EPA's national survey found
EPA tested this water for 30 substances and found 1.
Between August 2024 and May 2025, EPA's UCMR 5 program tested 360 samples from 3 sampling locations for 30 contaminants (29 PFAS plus lithium). 1 were detected above the reporting level in at least one sample.
Show the 29 contaminants not detected above the reporting level
Full table: samples, detections, highest single sample, complete-set average and sampling dates for all 30 contaminants
| Contaminant | Samples | Detections | Highest single sample | Complete-set average (results used) | EPA reference | Status | Sampled |
|---|---|---|---|---|---|---|---|
| PFPeA | 12 | 1 | 3.0 ppt | 0.8 ppt (4 of 4) | none set | detected; no EPA reference value | August 2024 – May 2025 |
| 11Cl-PF3OUdS | 12 | 0 | < 5.0 ppt | — | none set | not detected above the reporting level | August 2024 – May 2025 |
| 4:2 FTS | 12 | 0 | < 3.0 ppt | — | none set | not detected above the reporting level | August 2024 – May 2025 |
| 6:2 FTS | 12 | 0 | < 5.0 ppt | — | none set | not detected above the reporting level | August 2024 – May 2025 |
| 8:2 FTS | 12 | 0 | < 5.0 ppt | — | none set | not detected above the reporting level | August 2024 – May 2025 |
| 9Cl-PF3ONS | 12 | 0 | < 2.0 ppt | — | none set | not detected above the reporting level | August 2024 – May 2025 |
| ADONA | 12 | 0 | < 3.0 ppt | — | none set | not detected above the reporting level | August 2024 – May 2025 |
| HFPO-DA (GenX) | 12 | 0 | < 5.0 ppt | — | 10.0 ppt MCL (rescission proposed) · compared on the complete-set average | not detected above the reporting level | August 2024 – May 2025 |
| Lithium | 12 | 0 | < 9 ppb | — | 10 ppb health reference level · compared on the highest sample | not detected above the reporting level | August 2024 – May 2025 |
| NEtFOSAA | 12 | 0 | < 5.0 ppt | — | none set | not detected above the reporting level | August 2024 – May 2025 |
| NFDHA | 12 | 0 | < 20.0 ppt | — | none set | not detected above the reporting level | August 2024 – May 2025 |
| NMeFOSAA | 12 | 0 | < 6.0 ppt | — | none set | not detected above the reporting level | August 2024 – May 2025 |
| PFBA | 12 | 0 | < 5.0 ppt | — | 6,000 ppt screening level · compared on the highest sample | not detected above the reporting level | August 2024 – May 2025 |
| PFBS | 12 | 0 | < 3.0 ppt | — | 2,000 ppt health-based water concentration · compared on the highest sample | not detected above the reporting level | August 2024 – May 2025 |
| PFDA | 12 | 0 | < 3.0 ppt | — | none set | not detected above the reporting level | August 2024 – May 2025 |
| PFDoA | 12 | 0 | < 3.0 ppt | — | none set | not detected above the reporting level | August 2024 – May 2025 |
| PFEESA | 12 | 0 | < 3.0 ppt | — | none set | not detected above the reporting level | August 2024 – May 2025 |
| PFHpA | 12 | 0 | < 3.0 ppt | — | none set | not detected above the reporting level | August 2024 – May 2025 |
| PFHpS | 12 | 0 | < 3.0 ppt | — | none set | not detected above the reporting level | August 2024 – May 2025 |
| PFHxA | 12 | 0 | < 3.0 ppt | — | 3,000 ppt screening level · compared on the highest sample | not detected above the reporting level | August 2024 – May 2025 |
| PFHxS | 12 | 0 | < 3.0 ppt | — | 10.0 ppt MCL (rescission proposed) · compared on the complete-set average | not detected above the reporting level | August 2024 – May 2025 |
| PFMBA | 12 | 0 | < 3.0 ppt | — | none set | not detected above the reporting level | August 2024 – May 2025 |
| PFMPA | 12 | 0 | < 4.0 ppt | — | none set | not detected above the reporting level | August 2024 – May 2025 |
| PFNA | 12 | 0 | < 4.0 ppt | — | 10.0 ppt MCL (rescission proposed) · compared on the complete-set average | not detected above the reporting level | August 2024 – May 2025 |
| PFOA | 12 | 0 | < 4.0 ppt | — | 4.0 ppt MCL · compared on the complete-set average | not detected above the reporting level | August 2024 – May 2025 |
| PFOS | 12 | 0 | < 4.0 ppt | — | 4.0 ppt MCL · compared on the complete-set average | not detected above the reporting level | August 2024 – May 2025 |
| PFPeS | 12 | 0 | < 4.0 ppt | — | none set | not detected above the reporting level | August 2024 – May 2025 |
| PFTA | 12 | 0 | < 8.0 ppt | — | none set | not detected above the reporting level | August 2024 – May 2025 |
| PFTrDA | 12 | 0 | < 7.0 ppt | — | none set | not detected above the reporting level | August 2024 – May 2025 |
| PFUnA | 12 | 0 | < 2.0 ppt | — | none set | not detected above the reporting level | August 2024 – May 2025 |
Sampling-point average: mean of a location's two (ground water) or four (surface water) UCMR 5 results with non-detects counted as zero, EPA's method for comparing UCMR 5 data to the PFAS MCLs. EPA rounds to the reference value's significant digits before deciding whether an average is "greater than" an MCL (PFOA/PFOS averages count as above 4.0 ng/L only from 4.05 ng/L; lithium results count as above the 10 ppb reference only from 15 ppb). This site does not apply that rounding: "at or above" here means the measured value is numerically at or above the reference.
Every detection by sampling location (1 results)
| Date | Sampling location | Source water | Contaminant | Result | Reporting level |
|---|---|---|---|---|---|
| Nov 13, 2024 | WTP POE Ashburton Filter Plant | surface water | PFPeA | 3.0 ppt | 3.0 ppt |
Utility-reported context (UCMR 5 questionnaire, aggregated across sampling events): PFAS previously found at this system: yes at 12 of 12 sampling events; potential PFAS sources nearby: no at 9 of 12 sampling events, not known at 3 of 12 sampling events; PFAS treatment in place: no PFAS treatment at 12 of 12 sampling events.
Lead at customer taps
In the latest completed monitoring period, ending Dec 31, 2024, 9 in 10 sampled homes had lead at or below 2.7 ppb, below the 15 ppb action level that triggers utility action. The action level has been reached in 1 of the 16 periods on record.
In the most recent completed lead monitoring period, ending Dec 31, 2024, the 90th-percentile lead result at customer taps was 2.7 ppb, below the action level of 15 ppb; 1 of the 16 monitoring periods on record reached the action level. The 90th percentile is the value that 9 in 10 sampled homes were at or below. Values are in parts per billion (ppb).
| Monitoring period | Metal | 90th percentile | Action level | Status |
|---|---|---|---|---|
| Jan 1, 2022 – Dec 31, 2024 | Lead | 2.7 ppb | 15 ppb | below the action level |
| Jan 1, 2019 – Dec 31, 2021 | Lead | 3.5 ppb | 15 ppb | below the action level |
| Jan 1, 2016 – Dec 31, 2018 | Lead | 3 ppb | 15 ppb | below the action level |
| Jan 1, 2013 – Dec 31, 2015 | Lead | 5 ppb | 15 ppb | below the action level |
| Jan 1, 2010 – Dec 31, 2012 | Lead | 5 ppb | 15 ppb | below the action level |
| Jan 1, 2007 – Dec 31, 2009 | Lead | 7 ppb | 15 ppb | below the action level |
| Jan 1, 2004 – Dec 31, 2006 | Lead | 11 ppb | 15 ppb | below the action level |
| Jan 1, 2003 – Dec 31, 2003 | Lead | 10 ppb | 15 ppb | below the action level |
| Jan 1, 2002 – Dec 31, 2002 | Lead | 8 ppb | 15 ppb | below the action level |
| Jan 1, 2001 – Dec 31, 2001 | Lead | 11 ppb | 15 ppb | below the action level |
| Jan 1, 2000 – Dec 31, 2000 | Lead | 12 ppb | 15 ppb | below the action level |
| Jan 1, 1999 – Jun 30, 1999 | Lead | 10 ppb | 15 ppb | below the action level |
Show all 16 monitoring periods on record
| Monitoring period | Metal | 90th percentile | Action level | Status |
|---|---|---|---|---|
| Jan 1, 2022 – Dec 31, 2024 | Lead | 2.7 ppb | 15 ppb | below the action level |
| Jan 1, 2019 – Dec 31, 2021 | Lead | 3.5 ppb | 15 ppb | below the action level |
| Jan 1, 2016 – Dec 31, 2018 | Lead | 3 ppb | 15 ppb | below the action level |
| Jan 1, 2013 – Dec 31, 2015 | Lead | 5 ppb | 15 ppb | below the action level |
| Jan 1, 2010 – Dec 31, 2012 | Lead | 5 ppb | 15 ppb | below the action level |
| Jan 1, 2007 – Dec 31, 2009 | Lead | 7 ppb | 15 ppb | below the action level |
| Jan 1, 2004 – Dec 31, 2006 | Lead | 11 ppb | 15 ppb | below the action level |
| Jan 1, 2003 – Dec 31, 2003 | Lead | 10 ppb | 15 ppb | below the action level |
| Jan 1, 2002 – Dec 31, 2002 | Lead | 8 ppb | 15 ppb | below the action level |
| Jan 1, 2001 – Dec 31, 2001 | Lead | 11 ppb | 15 ppb | below the action level |
| Jan 1, 2000 – Dec 31, 2000 | Lead | 12 ppb | 15 ppb | below the action level |
| Jan 1, 1999 – Jun 30, 1999 | Lead | 10 ppb | 15 ppb | below the action level |
| Jul 1, 1998 – Dec 31, 1998 | Lead | 8 ppb | 15 ppb | below the action level |
| Jul 1, 1997 – Dec 31, 1997 | Lead | 8 ppb | 15 ppb | below the action level |
| Jan 1, 1997 – Jun 30, 1997 | Lead | 13 ppb | 15 ppb | below the action level |
| Jul 1, 1992 – Dec 31, 1992 | Lead | 15 ppb | 15 ppb | at or above the action level |
Drinking water violations since Sep 3, 2016
EPA lists 9 violations since Sep 3, 2016. 2 are health-based, meaning a contaminant or treatment rule was not met. The other 7 concern missed monitoring, reporting or public notices.
EPA's SDWIS database lists 9 violations recorded since Sep 3, 2016: 2 health-based (a contaminant above its maximum contaminant level, a disinfectant above its maximum residual level, or a required treatment technique not met), 6 for monitoring or reporting, 1 other (public notification or consumer confidence report requirements).
| Compliance period | Type | Contaminant / rule | Description | Records | Status |
|---|---|---|---|---|---|
| Jan 1, 2026 – Mar 31, 2026 | MCL · health-based | Tthm (81 UG/L, limit 80 UG/L) | Maximum Contaminant Level Violation, Average | 1 record | Archived · 3 enforcement actions |
| Sep 1, 2022 – Sep 30, 2022 | MCL · health-based | Revised Total Coliform Rule | Maximum Contaminant Level Violation, E. coli (RTCR) | 1 record | Resolved · 4 enforcement actions |
| Jul 2, 2025 | RPT | Lead and Copper Rule Revisions | Notification, Known or Potential LSL | 1 record | Resolved · 1 enforcement action |
| Apr 1, 2023 – Jun 30, 2023 | MR | Chlordane | Monitoring, Regular | 2 records at 2 facilities | Resolved · 4 enforcement actions |
| Apr 1, 2023 – Jun 30, 2023 | MR | Toxaphene | Monitoring, Regular | 2 records at 2 facilities | Resolved · 4 enforcement actions |
| Jan 1, 2023 – Dec 31, 2023 | MR | Nitrate | Monitoring, Regular | 1 record | Resolved · 4 enforcement actions |
| Sep 5, 2022 | Other | Public Notice | Public Notification Violation for NPDWR Violation | 1 record | Resolved · 2 enforcement actions |
Sanitary surveys and site visits
Most recent state inspection: Mar 20, 2026 (site visit); 11 visits since Sep 3, 2021.
What you can do about these results
Filters certified to reduce PFOA and PFOS
EPA testing found 1 PFAS above reporting levels in this utility's water.
Look for NSF/ANSI 53 (activated carbon) or NSF/ANSI 58 (reverse osmosis) certification that names PFOA/PFOS reduction.
Filters certified for lead reduction
1 of this utility's 16 lead monitoring periods on record reached the 15 ppb action level (most recent 90th percentile 2.7 ppb).
NSF/ANSI 53 with a lead-reduction claim, or NSF/ANSI 58 reverse osmosis. Lead comes from plumbing, so a point-of-use filter at the kitchen tap is the relevant type.
ZIP codes served
Sources
Data vintage: EPA UCMR 5 occurrence data, samples collected 2023-01-03 – 2026-06-17, final release, August 2026 (file dated Aug 28, 2026); EPA SDWIS via ECHO, 2026Q2 extract (file dated Jul 9, 2026); EPA service-area boundaries v3.0; Census 2020 ZCTAs. Page generated 2026-09-03.
- EPA ECHO detailed facility report
- EPA UCMR 5 Data Finder
- EPA service-area boundary: modeled, 272.7 sq mi
