District of Columbia Water Quality Report
Tap water quality data for 2 cities in District of Columbia, updated 2026.
US average: 100 ppm
2 of 2 cities violation-free
2 cities tested
2 water systems tracked
Cleanest Tap Water in District of Columbia
Cities with the fewest water quality issues
No cities in District of Columbia have recorded water quality violations in the past 3 years.
District of Columbia Tap Water: What You Need to Know
District of Columbia has 2 tracked water utilities serving approximately 632K residents. The average water hardness is 126 ppm (7.4 GPG), classified as Hard — above the national average of 100 ppm. Hardness ranges from 126 ppm in Washington to 126 ppm in Washington.
No cities in District of Columbia have recorded water quality violations in the past 3 years — an excellent compliance record. All 2 tested cities have lead levels below the EPA action level of 15 ppb.
With hard water on average, many District of Columbia residents may notice mineral buildup on fixtures, dry skin, or stiff-feeling hair. A shower filter for hard water can help reduce chlorine exposure, while a water softener addresses the mineral buildup directly.
Frequently Asked Questions About District of Columbia Water
Is tap water safe to drink in District of Columbia?
Based on available EPA data, no cities in District of Columbia have recorded water quality violations in the past 3 years. However, water quality can vary by building — older homes may have lead pipes. Consider testing your water at home for complete peace of mind.
How hard is the water in District of Columbia?
District of Columbia's average water hardness is 126 ppm (7.4 GPG), classified as Hard. This is above the national average of 100 ppm. Hardness varies significantly by city — use our Water Hardness Calculator to check your specific area.
Which city in District of Columbia has the cleanest tap water?
Based on EPA violation data, lead testing, and water quality metrics, D.c. ranks as having the cleanest tap water in District of Columbia. It has zero violations in the past 3 years and lead levels well below the EPA action level.
Where does District of Columbia get its water from?
The majority of District of Columbia's water systems (50%) use surface water as their primary source. Surface water comes from rivers, lakes, and reservoirs. Each city's specific source can vary — check individual city reports for details.
Largest Cities in District of Columbia
The 2 biggest utilities by population served — hardness, lead status, and violations at a glance