C

Fair — Average Score 70/100

Water Quality in District of Columbia

268 ZIP codes analyzed · Data updated March 2026

State Overview

About Water Quality in District of Columbia

Water quality across District of Columbia receives an overall grade of C (Fair) with an average score of 70 out of 100, based on EPA compliance data from 268 ZIP codes statewide. This is 5 points below the national average of 75, suggesting significant water quality challenges that affect residents statewide. Approximately 1% of ZIP codes (2 areas) receive a D or F grade, indicating communities with notable water quality concerns that warrant attention. The lowest-scoring area is ZIP code 20240 (Washington) with a score of 39/100. Scores are calculated from EPA Safe Drinking Water Information System (SDWIS) violation records, lead and copper testing results, PFAS monitoring data from UCMR5, and enforcement actions over the past 5 years.

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