Potomac, MD: Lead Above EPA Limits — 34/100 (2026)
2 ZIP codes · 3 water systems · Updated 2026-06-03
Water systems serving Potomac record elevated violation rates against MD benchmarks — residents in affected areas may want to check their local system's current compliance status.
How Potomac Compares
Data: EPA SDWIS Last verified: 2026-06-03
Potomac Water: The Quick Version
- Average lead level: 0.034 mg/L — exceeds the EPA action level of 0.015 mg/L.
- Estimated remediation: $4,250 per household.
- CDC health risk index: 10.24.
Water Systems Serving Potomac
Potomac, MD draws its residential water from 3 separate providers among the 3 federally tracked systems. Each operates independently, with its own infrastructure, rate structure, and compliance record.
Overview
We track water quality and home safety data for 2 ZIP codes in Potomac, Maryland (population ~49,694), covering 3 community water systems serving approximately 1,900,220 people region-wide.
No EPA violations recorded across any ZIP codes in Potomac — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for Potomac: F (34/100)
The score combines three factors:
| Factor | What It Measures |
|---|---|
| Water Quality | EPA violations and compliance history |
| Lead Levels | 90th percentile lead concentration vs EPA action level |
| Radon Risk | EPA radon zone classification |
Water Sources
Potomac water systems draw from: Groundwater.
Lead & Copper
- Average lead level (90th percentile): 0.0340 mg/L (exceeds EPA action level) (EPA action level: 0.015 mg/L)
- 2 ZIP codes exceed the EPA lead action level
Radon Risk
Dominant radon zone: Zone 1 (High Risk)
- Zone 1 (High): 2 ZIP codes
- Zone 2 (Moderate): 0 ZIP codes
- Zone 3 (Low): 0 ZIP codes
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
Areas with No Violations
| ZIP Code | Safety Score | System | Population |
|---|---|---|---|
| 20854 | F | WASHINGTON SUBURBAN SANITARY COMMISSION | 1,900,000 |
| 20859 | F | Woodbine Village Mobile Home Park | 150 |
All ZIP Codes in Potomac
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Lead/copper: EPA Lead and Copper Rule sampling data
- Radon: EPA Map of Radon Zones
Updated daily.
CDC Health Data for Potomac
Source: CDC PLACES (County-level estimates). Water contamination can correlate with respiratory and chronic health conditions.
Compared to National Average
Vertical line = national average. ■ Above national · ■ Below national
Potomac: Remediation Cost in Perspective
In Potomac, documented water and safety issues can be addressed without making a meaningful dent in home equity — the financial proportionality here is favorable, and the commitment fits within standard property planning frameworks.
Remediation costs in Potomac are relatively low compared to home values. The $2,800–$5,800 estimated range is a small fraction of median property value. Home values are 159% above the Maryland average.
Protecting Children from Lead in Potomac
Why children are most at risk: The CDC states there is no safe level of lead exposure for children. Children under 6 absorb lead more readily than adults, and even low levels can cause developmental delays, learning difficulties, and behavioral problems.
If you have young children or are pregnant, consider testing your home's water — especially if your home was built before 1986.
<strong>2 ZIP codes</strong> (100% of the city) exceed the EPA lead action level of 0.015 mg/L.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Climate-Related Water Risk for Potomac
Flood exposure in Potomac is meaningful by NFIP measures — 53 claims on record and 50% of ZIP codes carrying FEMA flood zone designations. That level of activity makes flood history a relevant factor when evaluating local water quality over time.
Potomac has a moderate flood history with 53 FEMA claims averaging $10,380 per payout. 50% of ZIP codes fall within FEMA flood zones. Flood events can contaminate drinking water and overwhelm treatment systems.
How flooding affects water quality: Flood events can introduce sewage, agricultural runoff, and industrial chemicals into water supplies. Even after floodwaters recede, contamination can persist in wells and aging infrastructure. Flood damage can add significantly to the estimated <strong>$4,250</strong> remediation cost per household.
Residents in flood-prone areas should consider flood insurance even outside FEMA zones — over 25% of flood claims come from low-to-moderate risk areas. After any flood event, test your water before drinking.
Source: FEMA National Flood Insurance Program (NFIP) claims data, FEMA flood zone designations.
What You Can Do in Potomac
- Test your water at home. City-level data shows averages — your tap may differ. Lead testing is especially recommended given the area's lead levels.
- Install a certified water filter. An NSF-certified pitcher or under-sink filter removes most common contaminants.
- Check your home's plumbing. Homes built before 1986 may have lead solder in pipes. A licensed plumber can assess your risk.
- Review your water system's CCR. Your utility publishes an annual Consumer Confidence Report with detailed test results. Request it or find it online.
Deep Dive Reports
Detailed analysis for Potomac, MD