Potomac, MD
WASHINGTON SUBURBAN SANITARY COMMISSION · Serves 1.9M people · Surface Water
contaminants
detected
exceed
guidelines
PFAS
chemicals
Most concerning
HAA9
1456×health limit
TraceAlso detected: Dibromochloromethane, chromium, Thallium, Nitrate, Bromoform, manganese, Atrazine, Fluoride, strontium, chlorate, Barium, PFPeA… (+21 more contaminants)
Enter your email to receive the latest report in PDF
The truth about legal limits
Legal does not equal safe.
Meeting EPA legal limits does not mean your water is safe for drinking.
We benchmark against the strictest independent health-based guidelines.
All Contaminants
31Filter by health risk
Critical findings — every contaminant in your water that exceeds the EWG health limit by 10× or more. Start here.
Filtration Analysis
Viven
Multi-stage
Activated
Carbon filter
Reverse
Osmosis only
PFAS / Forever Chemicals
Viven
99.9%Carbon
PartialRO only
YesHeavy Metals
Viven
99.9%Carbon
LimitedRO only
YesRadionuclides
Viven
99.9%Carbon
NoRO only
YesMinerals re-added
Viven
YesCarbon
NoRO only
NoContaminants in your water that Viven removes
Reserve nowFrequently asked
Potomac water quality questions
- Is tap water in Potomac, MD (ZIP 20859) safe to drink?
- Tap water for ZIP 20859, served by WASHINGTON SUBURBAN SANITARY COMMISSION, has 17 contaminants detected above independent EWG health guidelines, including HAA9 at 1456× the guideline. Meeting EPA legal limits does not necessarily mean water is safe — federal legal limits are often far higher than the latest health-based guidelines.
- What contaminants are in Potomac, MD tap water?
- EPA monitoring data for ZIP 20859 shows 31 contaminants detected, including HAA9, HAA5, TOTAL HALOACETIC ACIDS (HAA5), TTHM, HAA6Br, Trichloroacetic Acid. Each detected level is compared against both EPA legal limits and the stricter EWG health guidelines.
- Does Potomac, MD tap water have PFAS ("forever chemicals")?
- Yes — 2 PFAS compounds were detected out of 30 tested for ZIP 20859. PFAS are persistent synthetic chemicals linked to cancer, immune effects, and developmental harm, with no safe level of exposure established.
- How can I remove these contaminants from my drinking water?
- A multi-stage filtration system that combines activated carbon, reverse osmosis, and remineralization removes PFAS, heavy metals, and disinfection byproducts while restoring beneficial minerals. The Viven faucet is engineered to remove 99.9% of the contaminants found in tap water.
- Where does this Potomac, MD water quality data come from?
- This report is built from U.S. EPA data: the Unregulated Contaminant Monitoring Rule (UCMR 3/4/5), the Six-Year Review (SYR4), the Lead and Copper Rule (LCR), and SDWIS violation records. Detected levels are compared against EPA legal limits and Environmental Working Group (EWG) health guidelines. Data last updated 2026-05-01.
Check water quality for another area