Water quality · Colorado
Water quality in Colorado
Of the 8 Colorado ZIPs matched to an EPA SDWIS community water system, none reports a health-based violation in the last 3 years, though 7 carry at least one non-health-based violation. 2 further ZIPs have no water-system record on zipradar yet. That is a gap in our records, not a sign that the water is untested. SDWIS reports the system serving the county, never an address-level test, and never private wells.
Last verified 2026-09-24 · methodology
Water quality by ZIP code in Colorado
The largest community water system EPA lists for each ZIP's county, and its health-based violations in the last 3 years.
| ZIP | Largest system | Health-based violations |
|---|---|---|
| 80202DenverDenver County | DENVER WATER BOARD | None |
| 80206Denver (Cherry Creek)Denver County | No record yet | |
| 80424BreckenridgeSummit County | BRECKENRIDGE TOWN OF | None |
| 80302BoulderBoulder County | BOULDER CITY OF | None |
| 81611AspenPitkin County | ASPEN CITY OF | None |
| 80525Fort CollinsLarimer County | No record yet | |
| 81301DurangoLa Plata County | DURANGO CITY OF | None |
| 80205Denver (Five Points)Denver County | DENVER WATER BOARD | None |
| 80113Englewood (CO)Arapahoe County | ENGLEWOOD CITY OF | None |
| 80020Broomfield (CO)Broomfield County | BROOMFIELD CITY AND COUNTY OF | None |
County-level figures from EPA SDWIS, joined to each ZIP by county. None of them is a measurement at a specific address.
What lands here
Pages show the largest community water system on record for the ZIP's county, its PWSID and population served, and its health-based and total violations in the last 3 years. Lead and copper sampling results are not shown; your utility's annual water quality report (CCR) has them.
Source & refresh
EPA SDWIS. Refreshed quarterly (federal mandate). Primary source →
Colorado top concern
Radon Zone 1, wildfire on the Front Range
Colorado is one of the most uniformly Zone 1 radon states in the US. WUI wildfire risk concentrates along the Front Range from Boulder to Colorado Springs. Drinking water sourcing splits between Front Range water districts and Western Slope reclamation projects, each with distinct EPA SDWIS compliance histories.
See Colorado state page for the full state-level rollup across all 12 dimensions.
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EPA Radon Zones — what 1, 2, and 3 mean and when you should test
EPA classifies every US county into Zone 1 (high), Zone 2 (moderate), or Zone 3 (low) for radon. Plain-English guide to the classifications and at-home testing.
EPA AQI categories explained — what 0–50 Good through 301–500 Hazardous mean
Plain-English guide to the six EPA Air Quality Index categories: 0–50 Good, 51–100 Moderate, 101–150 Unhealthy for Sensitive Groups, 151–200 Unhealthy, 201–300 Very Unhealthy, 301–500 Hazardous — what each level means and who is at risk.
Lead and Copper Rule 2024 — the federal lead-pipe inventory mandate
The 2024 Lead and Copper Rule Revisions (LCRR) require every US community water system to inventory and report lead service lines. Plain-English guide.