Question 1

Which county in District of Columbia has the best water quality?

Accepted Answer

District of Columbia has the highest water quality score in District of Columbia at 100.0/100 (Grade: B), based on EPA SDWIS data.

Question 2

Which county in District of Columbia has the most water violations?

Accepted Answer

District of Columbia has among the lowest water quality scores in District of Columbia at 100.0/100. See the individual county page for detailed violation history.

Question 3

Is the tap water safe to drink in District of Columbia?

Accepted Answer

District of Columbia has an average water quality score of 100.0/100 based on EPA Safe Drinking Water Act compliance data. Individual county scores vary — check your specific county's page for detailed information.

Question 4

What contaminants are found in District of Columbia water supplies?

Accepted Answer

Drinking water quality varies by county and water system. The EPA Safe Drinking Water Information System (SDWIS) tracks violations for contaminants like lead, nitrates, bacteria, and disinfection byproducts. See individual county pages for specific contaminant and violation history.

District of Columbia Water Quality

All District of Columbia Counties

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