U.S. Water Quality & Home Safety Data by ZIP Code

U.S. drinking water quality and home safety data by ZIP code from EPA and 49 federal/state sources. Updated weekly. Erratum (v2, 2026-06-10): Versions of this dataset published before 2026-06-10 emitted enforcement_action_count=0, enforcement_health_violations=0, has_active_issues=false, and boil_water_advisories=0 for ZIP codes that had no enforcement record in the source (approximately 7,579 ZIPs). That conflated "data not available" with a measured zero / no-active-issues result. In v2 those four fields are emitted as null (empty in CSV) when the ZIP is absent from the enforcement source; a 0/false now appears only where it is a genuine measured value. A null means data not available, NOT measured-zero. See CHANGELOG.md and the erratum block in zipcheckup-metadata.json. (Precedent: CCR dataset v1 to v2 correction.)