PFAS in Drinking Water in Maryland
What residents of Maryland need to know about PFAS ("forever chemicals") in drinking water — including contamination sources, which utilities have documented violations, and how to filter PFAS from tap water.
Source: EPA SDWIS, Maryland Department of the Environment, CDC · Last reviewed: 2025-01-01
Quick Answer
Is PFAS in drinking water a real concern in Maryland?
Yes. Maryland has documented PFAS contamination from military installations including Naval Air Station Patuxent River (St. Mary's County), Aberdeen Proving Ground (Harford County), and Andrews Air Force Base/Joint Base Andrews (Prince George's County). These installations have documented AFFF-related PFAS in surrounding groundwater, and some nearby public water systems and private wells have reported detections.
Where does PFAS come from in Maryland?
Naval Air Station Patuxent River — Maryland's largest military installation — is the primary PFAS source in southern Maryland. AFFF from flight operations and fire training has contaminated surrounding groundwater in St. Mary's County. Aberdeen Proving Ground in Harford County has also generated PFAS plumes, and Joint Base Andrews near Washington, D.C., has documented contamination in Prince George's County.
What should Maryland residents know?
St. Mary's County near NAS Patuxent River, Harford County near Aberdeen Proving Ground, and Prince George's County near Joint Base Andrews have the highest documented PFAS risk in Maryland. Private well owners in these areas are especially vulnerable. Maryland MDE has expanded PFAS testing under UCMR5.
Key Facts
| EPA MCL (PFOA/PFOS) | 4 ppt — effective April 2024 |
| MCLG | Zero |
| Primary contamination sources | NAS Patuxent River (St. Mary's), Aberdeen Proving Ground (Harford), Joint Base Andrews (Prince George's) |
| State regulator | Maryland Department of the Environment (MDE) |
| Health effects | Cancer (kidney, testicular), thyroid disruption, immune effects, developmental toxicity |
| Private well risk | Rural St. Mary's, Harford, and southern Anne Arundel counties — test independently |
| Effective treatment | Reverse osmosis (NSF/ANSI 58) or activated carbon certified for PFAS |
Why PFAS Matters in Maryland
Maryland's military-industrial PFAS contamination spans the state from southern Maryland to the Baltimore suburbs to the D.C. suburbs. NAS Patuxent River — a major Navy test and evaluation facility — has one of the most extensive AFFF use histories in the Mid-Atlantic. Aberdeen Proving Ground, a major Army testing installation, has multiple legacy contamination concerns of which PFAS is one layer. The Washington, D.C. metro area's proximity to Joint Base Andrews and other federal facilities means some suburban Maryland residents face military-source PFAS exposure. Maryland MDE has been proactive in testing and in working with the military on remediation.
Maryland PFAS Regulation
Maryland MDE coordinates PFAS investigations at Aberdeen Proving Ground, Joint Base Andrews, Fort Meade, and Indian Head Naval Surface Warfare Center. The Chesapeake Bay watershed context means PFAS contamination affects shared water resources across the region. Maryland follows the federal MCL with no additional state standard.
Largest Maryland Water Utilities
No PFAS violations on record in EPA SDWIS for Maryland utilities in our database. Browse the largest utilities to review their full water quality record.
What Are PFAS (“Forever Chemicals”)?
PFAS are a family of over 12,000 synthetic chemicals used in non-stick cookware, stain-resistant fabrics, food packaging, and AFFF firefighting foam. Their carbon-fluorine bonds do not break down in the environment or the body — hence the name “forever chemicals.” AFFF used at military bases is the single largest source of PFAS in U.S. drinking water.
Full PFAS overview — national data, health effects, all 50 statesWho Should Pay Closest Attention
Residents of Lexington Park and rural St. Mary's County (near NAS Patuxent River), communities adjacent to Aberdeen Proving Ground in Harford County, and Prince George's County communities near Joint Base Andrews face the highest risk. Private well owners in these areas have no regulatory PFAS protection and should test independently.
Residents near military bases with AFFF use history
Private well owners near military or industrial sites
Pregnant residents and families with young children
Residents in communities with documented PFAS detections
Anyone who has consumed water above 4 ppt for an extended period
Residents near airports, fire training areas, or industrial manufacturers
How to Check Your Situation in Maryland
- 1
Identify your water utility using the ZIP lookup below or by browsing the Maryland utility directory on this site.
- 2
Review your utility's Consumer Confidence Report (CCR) — it must report PFAS monitoring results under UCMR5 and the new MCL.
- 3
Check the EPA's ECHO database for your utility's monitoring history. Look for PFAS, PFOA, PFOS, and related compound results.
- 4
Contact your utility directly and ask for their most recent PFAS test results and whether they are implementing treatment under the 2024 MCL.
- 5
If you use a private well near a military base, airport, or industrial facility, order a PFAS panel test from a state-certified laboratory. Tests typically cost $150–$400.
- 6
If PFAS is detected above 4 ppt in your source water, install a certified NSF/ANSI 58 reverse osmosis system or an NSF/ANSI 53-certified activated carbon filter rated for PFAS removal.
How to Remove PFAS from Tap Water
Reverse Osmosis (Best)
90–99% removal — NSF/ANSI 58 certified systems only
Certified Activated Carbon
Effective with NSF/ANSI 53 or 58 certification — verify before buying
Boiling concentrates PFAS. Standard pitcher filters and water softeners do not remove PFAS. Always verify NSF certification before purchasing.
Take Action Now
Look up your Maryland utility's PFAS monitoring history on the PFAS Watchlist below.
If your utility has detected PFAS above 4 ppt, install an NSF/ANSI 58-certified reverse osmosis system at your drinking tap.
Private well owners near military or industrial sites should order a PFAS panel test ($150–$400 at a state-certified lab).
Request your utility's most recent Consumer Confidence Report — PFAS results must be disclosed under the new 2024 MCL.
Frequently Asked Questions
Related Pages
PFAS — National Overview
All U.S. utilities with PFAS records
Maryland PFAS Watchlist
Live utility PFAS monitoring data
Maryland State Overview
All utilities and water quality data
Reverse Osmosis Guide
Removes 90–99% of PFAS
Activated Carbon Filter Guide
NSF/ANSI 53/58 certified options for PFAS
Arsenic in Drinking Water
Another priority contaminant
All Contaminants
Complete reference library
Data Sources & Provenance
All data on this page is sourced from official U.S. government or public datasets.
Find Your Utility
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Maryland Department of the Environment ↗