A well is only as good as its water quality, and unlike municipal water, nobody is testing it for you. Regular testing is the only way to actually know what’s in your water rather than assuming it’s fine because it looks and tastes normal.
What to Test For
At minimum, most well owners should test annually for bacteria (total coliform and E. coli) and nitrates, and periodically for factors specific to your region — arsenic, lead, radon, or agricultural runoff contaminants depending on local geology and land use. The EPA’s guidance for private well owners covers what’s recommended and how often.
How to Get It Tested
Your county or state health department often offers low-cost basic testing, and is usually the best first call since they’ll know what contaminants are common in your specific area. Private certified labs offer more comprehensive panels for a higher cost if you want to test for something specific, like agricultural chemicals near farmland.
What Affects Cost
A basic bacteria-and-nitrate test is inexpensive; a comprehensive panel covering heavy metals, VOCs, and other contaminants costs considerably more. Testing right after drilling a new well, and then annually afterward, is the standard recommendation — skipping years doesn’t save meaningfully and risks missing a developing problem.
If Something Comes Back Positive
A positive result doesn’t necessarily mean starting over — filtration systems exist for most common well water issues, from simple sediment filters to UV purification for bacteria to reverse osmosis for a broader range of contaminants. Which system you need depends entirely on what the test actually found, which is exactly why testing first matters more than guessing at a filter to install.
Protecting Your Well Going Forward
Keep septic systems, livestock areas, and chemical storage a safe distance from your wellhead, and have the well itself inspected periodically for cracks or seal failures that could let contaminants in. See our guide to off-grid water purification for filtration options once you know what you’re dealing with.