Colorado: Certified labs by state

Colorado treats private-well water quality largely as a homeowner responsibility: the Division of Water Resources handles well permits and construction oversight, CDPHE certifies drinking-water labs, and Colorado State University Extension provides most homeowner testing guidance. Official Colorado sources repeatedly highlight nitrate in rural vulnerable aquifers, naturally occurring arsenic in some parts of the state, and radionuclides such as radon and uranium as notable concerns. ([dwr.colorado.gov](https://dwr.colorado.gov/services/well-permitting?utm_source=openai))

Checked against official sources on October 4, 2026. Rules and links change; confirm with the office listed before you act.

Official resources in Colorado

CDPHE Drinking Water Laboratory Certification

Official CDPHE page for certified drinking-water laboratories in Colorado. ([theverygoodwatercompany.com](https://theverygoodwatercompany.com/labs/colorado?utm_source=openai))

Colorado Division of Water Resources — Well Permitting

Use this page for new or replacement well permits, the Well Permit Search, and homeowner guidance on permit records and allowable uses. ([dwr.colorado.gov](https://dwr.colorado.gov/services/well-permitting?utm_source=openai))

Colorado State University Extension — Selecting an Analytical Laboratory

CSU Extension explains which baseline private-well tests to order and says annual water testing is suggested. ([extension.colostate.edu](https://extension.colostate.edu/resource/selecting-an-analytical-laboratory/?utm_source=openai))

Colorado State University Extension — Nitrates in Drinking Water

Colorado-specific guidance on nitrate sources, health risks, and how often well owners should test for nitrate. ([extension.colostate.edu](https://extension.colostate.edu/resource/nitrates-in-drinking-water/?utm_source=openai))

Colorado State University Extension — Well Water Contamination Assessment

A Colorado checklist residents can use to judge whether their well is vulnerable to contamination from septic systems, fuels, pesticides, and other hazards. ([extension.colostate.edu](https://extension.colostate.edu/resource/well-water-contamination-assessment/?utm_source=openai))

Key facts for Colorado

CDPHE's Laboratory Services Division runs Colorado's Drinking Water Laboratory Certification program. ([theverygoodwatercompany.com](https://theverygoodwatercompany.com/labs/colorado?utm_source=openai))
Colorado DWR issues permits for new or replacement wells and provides a Well Permit Search tool. ([dwr.colorado.gov](https://dwr.colorado.gov/services/well-permitting?utm_source=openai))
CSU suggests baseline well tests for bacteria, nitrate, sulfate, chloride, pH, TDS, hardness, and conductivity; annual testing is suggested. ([extension.colostate.edu](https://extension.colostate.edu/resource/selecting-an-analytical-laboratory/?utm_source=openai))
CSU says nitrate contamination above the MCL occurs mainly in rural Colorado areas overlying vulnerable aquifers. ([extension.colostate.edu](https://extension.colostate.edu/resource/nitrates-in-drinking-water/?utm_source=openai))
Official Colorado cancer-plan materials urged at least one arsenic test, especially in northeastern and southern Colorado. ([cdphe.colorado.gov](https://cdphe.colorado.gov/sites/cdphe/files/DC_Cancer_Plan-Public-Comment-SurveyMonkey.pdf?utm_source=openai))
CSU notes Colorado has naturally occurring radon and uranium; radon water testing is recommended when indoor-air radon is high and the source is groundwater. ([waterknowledge.colostate.edu](https://waterknowledge.colostate.edu/hydrology/water-quality/?utm_source=openai))

What to do next

Start by pulling your well permit and allowable uses from DWR's Well Permit Search, especially before buying property or replacing a well. ([dwr.colorado.gov](https://dwr.colorado.gov/services/well-permitting?utm_source=openai))
Choose a CDPHE-certified lab, request the CSU baseline private-well panel, and keep results so you can compare changes year to year. ([theverygoodwatercompany.com](https://theverygoodwatercompany.com/labs/colorado?utm_source=openai))
Test nitrate yearly; if results are high or borderline, CSU recommends retesting every three to six months. ([extension.colostate.edu](https://extension.colostate.edu/resource/nitrates-in-drinking-water/?utm_source=openai))

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