Loading water data...
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 6 cities serving 398,992 residents
Montgomery County in Maryland has an average water quality score of 83/100 (Grade B+) based on analysis of 6 municipal water systems. The county's water systems serve approximately 398,992 residents.
Overall, Montgomery County demonstrates good water quality standards. 5 of 6 cities exceed the county average, with Gaithersburg leading with a score of 93/100.
6 cities ranked by water quality score
| Rank | City | Score | Grade | Population |
|---|---|---|---|---|
| 1 | Gaithersburg Top concern: Haloacetic Acids (16.6% of limit) | 93 | A | 67,750 |
| 2 | Takoma Park Top concern: Total Trihalomethanes (16.9% of limit) | 89 | A- | 17,186 |
| 3 | Silver Spring Top concern: Fluoride (19.2% of limit) | 88 | A- | 80,907 |
| 4 | Bethesda Top concern: Total Trihalomethanes (18.4% of limit) | 88 | A- | 66,273 |
| 5 | Rockville Top concern: Lead (34.9% of limit) | 85 | A- | 70,922 |
| 6 | Germantown Top concern: Total Trihalomethanes (66.8% of limit) | 55 | C- | 95,954 |
Top detected contaminants across county water systems
| Contaminant | Avg Level | Max Level | EPA Limit | % of Limit | Cities |
|---|---|---|---|---|---|
| Total Trihalomethanes | 20.658 ug/L | 53.409 ug/L | 80 ug/L | 25.8% | 5 |
| Lead | 0.003 mg/L | 0.01 mg/L | 0.015 mg/L | 22.8% | 6 |
| Haloacetic Acids | 12.116 ug/L | 16.833 ug/L | 60 ug/L | 20.2% | 3 |
| Fluoride | 0.756 mg/L | 1.39 mg/L | 4 mg/L | 18.9% | 6 |
| Arsenic | 0.002 mg/L | 0.004 mg/L | 0.01 mg/L | 18.3% | 4 |
| Mercury | 0 mg/L | 0.001 mg/L | 0.002 mg/L | 17.5% | 6 |
| Chromium | 0.014 mg/L | 0.03 mg/L | 0.1 mg/L | 14.3% | 6 |
| Nitrite | 0.111 mg/L | 0.199 mg/L | 1 mg/L | 11.1% | 6 |
Recent violations across county water systems
Showing 10 of 13 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 6 municipal water systems serving a combined population of over 398,992 residents.
The county shows strong water quality performance, with scores ranging from 55/100 in Germantown to 93/100 in Gaithersburg. This 38-point spread indicates significant variation in water quality across the county, suggesting different water sources or treatment approaches.
The most prevalent contaminants detected across Montgomery County water systems include Total Trihalomethanes, Lead, Haloacetic Acids. All monitored contaminants remain within acceptable levels relative to EPA Maximum Contaminant Levels (MCLs).
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 83/100 (Grade B+) based on analysis of 6 municipal water systems serving 398,992 residents.
Gaithersburg has the highest water quality score in Montgomery County at 93/100. View the detailed report for Gaithersburg.
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.