34 named for arsenic itself on the list.
Per the state list or a state web page. Call to confirm.
Located outside Colorado but on its list.
USGS estimate for Colorado.
How many labs test for arsenic in Colorado
34 labs on Colorado's official drinking-water lab list are certified to test for arsenic. All 34 are named for arsenic on the list. 24 of them are marked as taking samples from the public. They are listed first. 16 are located outside Colorado.
The list is published by the Colorado Department of Public Health and Environment (CDPHE) - Laboratory Services Division, Drinking water lab certification. List version on file: Live report, no edit date shown; data read by the report at 2026-11-02 20:39 UTC (Looker Studio dataTimestamp). Fetched 2026-11-02 (UTC).
Colorado labs certified for arsenic
Marked as taking public samples (24)
| Lab | Location | Arsenic certification | Public samples | Cert. expiry |
|---|---|---|---|---|
| ACZ Laboratories, Inc. | Steamboat Springs, CO | Named on the official list | Public samples: yes (per state) | Not on the list |
| Alliance Technical Group, LLC-Akron | Cuyahoga Falls, OH | Named on the official list | Public samples: yes (per state) | Not on the list |
| Chemtech - Ford Laboratories | Sandy, UT | Named on the official list | Public samples: yes (per state) | Not on the list |
| Colorado Analytical Laboratory - Commerce City | Commerce City, CO | Named on the official list | Public samples: yes (per state) | Not on the list |
| Continental Water Laboratory | Sacramento, CA | Named on the official list | Public samples: yes (per state) | Not on the list |
| Culligan Analytical Laboratory | Rosemont, IL | Named on the official list | Public samples: yes (per state) | Not on the list |
| Eagle River W / S District | Avon, CO | Named on the official list | Public samples: yes (per state) | Not on the list |
| Energy Laboratories - Billings | Billings, MT | Named on the official list | Public samples: yes (per state) | Not on the list |
| Environmental Science Corp.dba PACE TN | Mt. Juliet, TN | Named on the official list | Public samples: yes (per state) | Not on the list |
| Eurofins Lancaster Laboratories Environment Testing, LLC | Lancaster, PA | Named on the official list | Public samples: yes (per state) | Not on the list |
| Eurofins Pomona - CA | Pomona, CA | Named on the official list | Public samples: yes (per state) | Not on the list |
| Eurofins South Bend - IN | South Bend, IN | Named on the official list | Public samples: yes (per state) | Not on the list |
| GEL Laboratories, LLC | Charleston, SC | Named on the official list | Public samples: yes (per state) | Not on the list |
| Hazen Research | Golden, CO | Named on the official list | Public samples: yes (per state) | Not on the list |
| National Testing Laboratories | Ypsilanti, MI | Named on the official list | Public samples: yes (per state) | Not on the list |
| Pace Analytical Services - FL | Ormond Beach, FL | Named on the official list | Public samples: yes (per state) | Not on the list |
| Pace Analytical Services - MN | Minneapolis, MN | Named on the official list | Public samples: yes (per state) | Not on the list |
| RTI International | Durham, NC | Named on the official list | Public samples: yes (per state) | Not on the list |
| Sangre De Cristo Laboratory | Alamosa, CO | Named on the official list | Public samples: yes (per state) | Not on the list |
| SGS North America, Inc. - Dayton | Dayton, NJ | Named on the official list | Public samples: yes (per state) | Not on the list |
| SGS North America, Inc. - Denver | Denver, CO | Named on the official list | Public samples: yes (per state) | Not on the list |
| SGS North America, Inc. - Wheat Ridge | Wheat Ridge, CO | Named on the official list | Public samples: yes (per state) | Not on the list |
| SPL, Inc. Reading | Reading, PA | Named on the official list | Public samples: yes (per state) | Not on the list |
| Weld County Department of Public Health & Environment | Greeley, CO | Named on the official list | Public samples: yes (per state) | Not on the list |
Other labs on the list (10)
| Lab | Location | Arsenic certification | Public samples | Cert. expiry |
|---|---|---|---|---|
| Denver Water - National Western Complex | Denver, CO | Named on the official list | Not marked as taking public samples | Not on the list |
| Parker Water & Sanitation District | Parker, CO | Named on the official list | Not marked as taking public samples | Not on the list |
| Ute Water Conservancy District | Palisade, CO | Named on the official list | Not marked as taking public samples | Not on the list |
| Aurora, City of | Aurora, CO | Named on the official list | Not marked as taking public samples Looks like a utility or municipal lab, judging by the name (our label, not the state list) | Not on the list |
| Broomfield, City & County - WWTP | Broomfield, CO | Named on the official list | Not marked as taking public samples Looks like a utility or municipal lab, judging by the name (our label, not the state list) | Not on the list |
| Colorado Springs Utilities | Colorado Springs, CO | Named on the official list | Not marked as taking public samples Looks like a utility or municipal lab, judging by the name (our label, not the state list) | Not on the list |
| Fort Collins, City of | Fort Collins, CO | Named on the official list | Not marked as taking public samples Looks like a utility or municipal lab, judging by the name (our label, not the state list) | Not on the list |
| Grand Junction, City of - WWTP AKA Persigo | Grand Junction, CO | Named on the official list | Not marked as taking public samples Looks like a utility or municipal lab, judging by the name (our label, not the state list) | Not on the list |
| Loveland, City of - WQL | Loveland, CO | Named on the official list | Not marked as taking public samples Looks like a utility or municipal lab, judging by the name (our label, not the state list) | Not on the list |
| Pueblo Board of Water Works | Pueblo, CO | Named on the official list | Not marked as taking public samples Looks like a utility or municipal lab, judging by the name (our label, not the state list) | Not on the list |
How the Colorado list marks public samples (whole list). Per lab, from CDPHE's column "Accepts Outside Samples": Yes means the lab takes samples from outside its own organisation, so call first to ask about a household sample, its bottles and its fees; No (utility and municipal labs that test only their own system's water) is shown as not accepting homeowners' samples. CDPHE's 'Water testing services' page sends well owners to this list: "Refer to the list of other accredited laboratories that may be able to accept your samples."
Before you send a sample, call the lab to confirm it is currently certified for the exact test and method, that it accepts samples from homeowners, and how to collect and ship them. Status can change between list updates.
Why test for arsenic in Colorado
Arsenic is invisible, tasteless and mostly natural, and it comes in two forms that respond very differently to treatment. Read our arsenic explainer.
Colorado guidance that mentions arsenic:
- Colorado's health department (CDPHE) recommends testing every year for total coliform bacteria, total dissolved solids, nitrate/nitrite and pH, and every 3 to 5 years for arsenic, copper, fluoride, hardness, iron, lead, manganese and uranium. For a new well or a well with no known testing, it lists a broader panel that includes PFAS and a volatile organic compound (VOC) screen. It says more frequent testing may be needed if pregnant or breastfeeding people, small children or elderly adults drink the water. [1]
USGS estimates that the most private-well users with arsenic above 10 µg/L, EPA's limit for public water, live in Alamosa County, El Paso County and Rio Grande County (about 2,831 people in Alamosa County, 2010 base year). USGS describes this kind of estimate as useful "for broad screening of the population at risk", so it says nothing certain about any one well. [2]
Show the numbers
| Item | Value | Note |
|---|---|---|
| Alamosa County | 2,831 people (2010 base year) | |
| El Paso County | 1,547 people (2010 base year) | |
| Rio Grande County | 1,382 people (2010 base year) | |
| Elbert County | 1,257 people (2010 base year) | |
| Douglas County | 997 people (2010 base year) | |
| Adams County | 697 people (2010 base year) |
USGS model estimate for broad screening, not a measurement of any well. Only a test tells you about your own well. Source: USGS, Estimated county level domestic well population with arsenic greater than 10 micrograms per liter (Ayotte, Medalie and Qi, 2017), accessed 2026-11-01.
About 286,474 people in Colorado used private wells in 2015, by the USGS estimate of people on domestic self-supplied water. [3] Federal limits are written for public water systems, not private wells, so testing is up to the owner.
For tests that depend on your home (farms nearby, old plumbing, a new baby), use the which-tests checklist. When results arrive, check your numbers against EPA's limits. State guidance, county data and every lab: Colorado.
Other tests in Colorado
- Colorado Department of Public Health and Environment (Colorado Environmental Public Health Tracking), Private well water and your health
- USGS, Estimated county level domestic well population with arsenic greater than 10 micrograms per liter (Ayotte, Medalie and Qi, 2017)
- USGS, Estimated use of water in the United States, county-level data for 2015 (Dieter et al., ver. 2.0, 2018)
- CDPHE Drinking Water Lab Certifications (Looker Studio report on cdphe.colorado.gov/dwlabs) (official list)
CDPHE Drinking Water Lab Certifications (Looker Studio report on cdphe.colorado.gov/dwlabs).
Official source