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Not health advice. Contact your local water utility for concerns.
Data from EPA Water Quality Reports. For official information, contact your water utility or health department.
Water quality data for 1 cities serving 52,000 residents
Montgomery County in Maryland has an average water quality score of 84/100 (Grade B) based on analysis of 1 municipal water systems. The county's water systems serve approximately 52,000 residents.
Overall, Montgomery County demonstrates good water quality standards. 1 of 1 cities exceed the county average, with Rockville leading with a score of 84/100.
1 cities ranked by water quality score
| Rank | City | Score | Grade | Population |
|---|---|---|---|---|
| 1 | Rockville Biggest deduction: 16 monitoring/reporting violations in the last 5 years (−10 pts) | 84 | B | 52,000 |
Real EPA readings across county water systems (lead: latest 90th percentile; PFAS: UCMR5 2023–2026; others: 2012–2019 averages)
| Contaminant | Avg Level | Max Level | EPA Limit | % of Limit | Cities |
|---|---|---|---|---|---|
| TTHM (2012–2019 avg) | 50.206 ug/L | 50.206 ug/L | 80 ug/L | 62.8% | 1 |
| HAA5 (2012–2019 avg) | 26.948 ug/L | 26.948 ug/L | 60 ug/L | 44.9% | 1 |
| Nitrate (2012–2019 avg) | 1.363 mg/L | 1.363 mg/L | 10 mg/L | 13.6% | 1 |
| Fluoride (2012–2019 avg) | 0.526 mg/L | 0.526 mg/L | 4 mg/L | 13.2% | 1 |
| Lead (90th percentile) | 0 ppb | 0 ppb | 15 ppb | 0% | 1 |
| PFAS (PFOA/PFOS max, UCMR5) | 0 ppt | 0 ppt | 4 ppt | 0% | 1 |
| Arsenic (2012–2019 avg) | 0 ug/L | 0 ug/L | 10 ug/L | 0% | 1 |
Recent violations across county water systems
Showing 10 of 16 recent violations
Water quality in Montgomery County, Maryland reflects the region's unique combination of water sources, treatment infrastructure, and environmental factors. Our comprehensive analysis examines 1 municipal water systems serving a combined population of over 52,000 residents.
The county shows strong water quality performance, with scores ranging from 84/100 in Rockville to 84/100 in Rockville. This 0-point spread indicates relatively consistent water quality standards across municipal systems.
The most prevalent contaminants detected across Montgomery County water systems include TTHM (2012–2019 avg), HAA5 (2012–2019 avg), Nitrate (2012–2019 avg). At least one reading averages above 50% of its EPA limit across the county's systems, worth attention from residents and utilities.
Montgomery County's water quality is generally good. Residents can feel confident in their tap water quality, though those with specific health concerns or sensitivity to certain contaminants may still benefit from filtration. Regular review of your city's annual Consumer Confidence Report is recommended.
Montgomery County has an average water quality score of 84/100 (Grade B) based on analysis of 1 municipal water systems serving 52,000 residents.
Rockville has the highest water quality score in Montgomery County at 84/100. View the detailed report for Rockville.
Most cities in Montgomery County have water that meets EPA standards. However, a water filter can provide additional protection and improve taste. The need depends on your specific city and any personal health considerations.
Click on any city in the rankings table above to view its detailed water quality report, including contaminant levels, EPA compliance history, and filter recommendations.