About this list
- Agency
- U.S. EPA Region 8 - Drinking Water Laboratory Certification (Wyoming has no state drinking-water program of its own: EPA Region 8 runs it and certifies Wyoming's labs)
- Format
- 1-page PDF matrix, analyte-level (inorganics, disinfection byproducts, microbiology, radionuclides, synthetic organics, VOC)
- Homeowner flag
- Yes for the 6 labs that Wyoming DEQ's Know Your Well page lists under "Find a Laboratory": "This information is provided to assist homeowners in finding an analytical laboratory for water analysis, inclusion on this list does not indicate WDEQ endorsement of the lab or the services provided." Call first. Not stated for the other 6 labs (utility, park, hospital and county labs). EPA's list itself is written for public water systems.
Partial list. Only the labs that EPA Region 8 certifies itself are listed. EPA Region 8 also accepts labs certified by other states ("reciprocal certification"); those labs are not on this list.
EPA Region 8 Certified Drinking Water Laboratories in Wyoming. Fetched 2026-11-15 (UTC).
Official sourceTesting your well in Wyoming
How often to test
- Wyoming DEQ recommends testing for bacteria (E. coli, total coliform) and nitrates every year, and for arsenic, lead, copper, iron, manganese, sulfate and total dissolved solids every five years. It notes that uranium, radium, selenium and methane are also common in Wyoming groundwater, and that owners in areas of possible oil and gas development should test for more. [1]
- DEQ also says to test right away if the taste, color or odor of your water changes or someone in the household has an unexplained illness, and to test when someone in the home is pregnant, an infant, elderly or has a health condition. [1]
Free testing
We found no statewide free testing program in Wyoming. Ask your county health department whether it runs one.
Testing programs and help
- DEQ's Know Your Well program helps private well owners with water quality questions, including reading lab results. DEQ also points owners to the Be Well Informed web tool, which Wyoming partners on, to check results against drinking water standards. [1]
- DEQ says local health departments in Wyoming can give information and guidance on well water testing and health effects. [1]
State lab and rules
- DEQ's Find a Laboratory list (which includes the Wyoming Department of Agriculture Analytical Lab) is meant to help homeowners find a lab and is not an endorsement. DEQ says to check prices with each lab and to ask it for bottles and sampling instructions. [1]
- EPA Region 8 certifies Wyoming laboratories for drinking water tests, analyte by analyte. [2]
Show the numbers
| Item | Value | Note |
|---|---|---|
| Zone 1 | 21 counties | |
| Zone 2 | 2 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.
- Wyoming Department of Environmental Quality, Know Your Well
- U.S. EPA Region 8, Certified Drinking Water Laboratories for Systems in Wyoming and on Tribal Lands in EPA Region 8 (last updated Feb 18, 2026)
- U.S. EPA, Map of Radon Zones, county list (EPA 402/A-16/001, spreadsheet Sep 2025)
Loan test (FHA, VA, USDA) in Wyoming
- 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.
Labs by contaminant
Labs on the Wyoming 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.