About this list
- Agency
- Colorado Department of Public Health and Environment (CDPHE) - Laboratory Services Division, Drinking water lab certification
- Format
- Interactive report (Google Looker Studio, 'Drinking Water Lab Certifications') on CDPHE's page: one row per lab, analyte and method, with lab status (Active/Expired), city/state/ZIP and 'Accepts Outside Samples'; analyte-level; no street address, phone or expiry date
- Homeowner flag
- 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."
Certified as ofLive report, no edit date shown; data read by the report at 2026-11-02 20:39 UTC (Looker Studio dataTimestamp)
CDPHE Drinking Water Lab Certifications (Looker Studio report on cdphe.colorado.gov/dwlabs). Fetched 2026-11-02 (UTC).
Official sourceTesting your well in Colorado
How often to test
- 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]
- CDPHE also says to test if someone in the home becomes pregnant or a child moves in, if people get unexplained stomach illness, if contaminants are found in a neighbor's well, if the water's taste, odor, color or clarity changes, after a spill near the well, after any well repair or part replacement, and after a nearby flood or fire. In areas with historic mining, it suggests you may consider a general metals panel. [1]
- Colorado State University Extension says wells used for drinking water should be tested for coliform bacteria every one to two years, along with other water quality parameters, and more often if the well is in poor condition, has been flooded, the septic system has failed, abandoned wells or feed yards are nearby, or visitors have had stomach or intestinal trouble. Its well-care checklist also says to have the well tested once a year for coliform bacteria, nitrate and other contaminants of concern. [2]
Free testing
- Anyone with a private well in Colorado can apply to CDPHE's PFAS Testing and Assistance Program (PFAS TAP) for free PFAS testing: a kit is mailed to you, you collect the sample and mail it back with a prepaid label. Households that use the well for drinking and cooking and have PFAS above EPA's drinking water standard can get a free filter dispenser and one year of replacement filters; results from an independent lab test can also qualify. CDPHE says the program is available while supplies last. In 2026 it is doing targeted outreach with Boulder County and the San Luis Valley. [3]
Testing programs and help
- CDPHE says your local public health agency may offer annual water testing, and suggests contacting it or CDPHE's ToxCall line with questions about what to test for. [1]
- CDPHE publishes a list of labs it has confirmed can test private well water. It does not endorse any lab, says the list is not exhaustive, and recommends calling the lab to confirm the method, contaminants and price. It notes that results from some labs may not meet the criteria for state or federal assistance programs. [1]
- CDPHE's online well water tool lets you enter your lab results and compare them with drinking water guidelines. CDPHE notes that drinking water standards do not apply to private wells, but you can still use them to assess your water. [4]
State lab and rules
- As of November 2026, the Colorado State Public Health Laboratory has temporarily suspended water chemistry testing to address quality control issues and has no timeline for reopening; it encourages using an accredited lab instead. Bacterial testing is not affected: the lab still tests for total coliform and E. coli. Well owners and real estate agents can order sample bottles, which the lab ships by FedEx at no cost. Samples must reach the lab within 24 hours of collection, payment is due when you submit the sample, and most results are ready within 72 hours. The lab says it cannot point you to a specific outside lab, because it certifies the labs on its list. [5]
- CDPHE certifies labs that test Colorado public drinking water and inspects them on site every two years. Approved testing may include chemistry, radiochemistry and microbiology. [6]
- CDPHE does not regulate water quality in private wells; only public water systems are regulated. Well permits are issued by the Colorado Division of Water Resources. [7]
Show the numbers
| Item | Value | Note |
|---|---|---|
| Zone 1 | 53 counties | |
| Zone 2 | 11 counties | |
| Zone 3 | 0 counties |
Radon in indoor air, not in water. EPA: Zone 1 = highest potential (average indoor radon may be above 4 pCi/L); Zone 2 = 2 to 4; Zone 3 = below 2. EPA says the map should not be used to decide whether an individual home needs testing. Source: U.S. EPA, Map of Radon Zones, county list (EPA 402/A-16/001, spreadsheet Sep 2025), accessed 2026-11-01.
Sources
- Colorado Department of Public Health and Environment (Colorado Environmental Public Health Tracking), Private well water and your health
- Colorado State University Extension, Bacteria in Water Wells (published Dec 2005, reviewed Aug 2025)
- Colorado Department of Public Health and Environment, PFAS Testing and Assistance Program (PFAS TAP)
- Colorado Department of Public Health and Environment (Colorado Environmental Public Health Tracking), Understanding your well water test results
- Colorado Department of Public Health and Environment, State Public Health Laboratory, Water testing services
- Colorado Department of Public Health and Environment, Drinking water lab certification
- Colorado Department of Public Health and Environment, Drinking water: Private wells
- U.S. EPA, Map of Radon Zones, county list (EPA 402/A-16/001, spreadsheet Sep 2025)
Loan test (FHA, VA, USDA) in Colorado
- VA. Test results are valid for 90 days from the date the local health authority certifies them, unless the local authority says otherwise. VA’s chapter names no list of contaminants: the water must meet the local health authority’s requirements, or EPA guidelines where it has none. Your lender may ask for specific tests.
- FHA. A well test is required in the situations FHA’s handbook lists, among others, and the report may not be more than 180 days old at disbursement.
- USDA. Guaranteed loans need a water quality test for a private well, done by the local health authority or a state-certified lab, and no more than 180 days old at closing.
Lenders can ask for more (extra tests, a particular lab, who takes the sample): ask your lender before you book. Federal rules as read on Nov 3, 2026 source 1 source 2 source 3. Full comparison: VA, FHA and USDA well water test requirements. Loan test kits sold by mail, with price and days to results: kits compared.
What Colorado labs say on their own websites
State lists say what a lab is certified for, not whether it takes your sample or what it costs. We read each lab’s own site; a second reader re-checked every fact below. 7 labs on this list are on our register so far; 2 say they take homeowner samples and 2 print a price.
| Lab | Bacteria (coliform / E. coli) | Nitrate | Arsenic | Lead | Basic well panel | Home sale / loan package | Turnaround |
|---|---|---|---|---|---|---|---|
| Colorado State University Fort Collins, CO · You collect the sample with the lab's bottles | – | W4 $40.00 Nitrate-N (NO3-N) and Ammonium (NH4+) source | – | – | W1 $87.00 Household Drinking Water Suitability source | – | You will receive the soil testing report within 7 to 10 business days after the laboratory receives your sample. |
| Three Lakes W/S District Grand Lake, CO · You collect the sample with the lab's bottles | The test cost is $50.00. Public Water System and bulk purchases of 10 or more tests are $45.00. source | – | – | – | – | – | – |
Say they take homeowner samples: Colorado State University, Three Lakes W/S District.
Prices exactly as each lab prints them, read 15 Nov 2026; re-checked every 90 days. Labs not shown have not been read yet or print nothing for homeowners. Confirm price and turnaround with the lab.
Labs by contaminant
Labs on the Colorado list for one test, with homeowner-accepting labs first.
Well water by county
Private-well population (USGS, 2015), arsenic estimate, radon zone and nearby labs for each county with at least 1,000 people on private wells, largest first.
El Paso County37,721 on wellsDouglas County22,037 on wellsJefferson County19,654 on wellsElbert County18,555 on wellsPark County13,840 on wellsGarfield County12,845 on wellsAdams County12,327 on wellsDelta County7,259 on wellsFremont County7,252 on wellsAlamosa County6,656 on wellsLogan County6,516 on wellsTeller County6,215 on wellsArapahoe County5,576 on wellsChaffee County5,438 on wellsLa Plata County5,298 on wellsMontezuma County4,838 on wellsPitkin County4,727 on wellsRio Grande County4,623 on wellsMesa County4,333 on wellsYuma County3,796 on wellsMoffat County3,787 on wellsArchuleta County3,762 on wellsBoulder County3,672 on wellsConejos County3,630 on wellsPueblo County3,571 on wellsLake County3,365 on wellsSummit County3,307 on wellsClear Creek County3,253 on wellsEagle County3,245 on wellsMontrose County2,926 on wellsSan Miguel County2,749 on wellsWashington County2,524 on wellsCuster County2,455 on wellsBent County2,360 on wellsKit Carson County2,328 on wellsWeld County2,114 on wellsGilpin County1,878 on wellsRio Blanco County1,851 on wellsCrowley County1,812 on wellsLas Animas County1,748 on wellsMorgan County1,720 on wellsSaguache County1,541 on wellsRoutt County1,490 on wellsGunnison County1,467 on wellsCostilla County1,454 on wellsOtero County1,253 on wellsOuray County1,221 on wellsGrand County1,185 on wellsPhillips County1,139 on wellsBaca County1,085 on wellsLarimer County1,057 on wellsDolores County1,028 on wells