How often should you test your well water in North Carolina?

The recommended schedule

Private wells aren't regulated the way city water is, so nobody tests yours unless you do. NC DHHS puts it plainly: as a private well owner, it's up to you to test your water.^[source] Here's the schedule it recommends:

NC DHHS also recommends checking the wellhead once a year to make sure it works properly and has no cracks or openings where contaminants could get in.^[source] That's a visual check you can do yourself: look at the cap, the casing and the ground around it.

Why repeat metals if they come from rock that doesn't change much? Because plumbing ages, well conditions shift, and NC DHHS notes that many North Carolina wells have too much lead, arsenic, iron, manganese or low pH.^[source] Some of those, like iron, announce themselves with stains; others, like arsenic, give no visible sign, so only a lab result tells you. Our guides on arsenic in Union County wells and low pH and pinhole leaks show how common some of these are locally.

When to test outside the schedule

NC DHHS lists situations that call for additional testing.^[source] If any of these apply, don't wait for the calendar:

• After a repair or replacement of any part of the well system, since contaminants can get in while it's open.^[source]
• After flooding, especially if the wellhead was under water.^[source]
• After problems near the well, such as land disturbance, construction or a nearby waste disposal site.^[source]
• When taste, color or odor changes.^[source]
• When there are known problems with well water in your area.^[source]
• If someone in the home is pregnant or there's an infant, NC DHHS says to test for nitrates. It also notes that boiling doesn't remove nitrates.^[source]

If you have treatment equipment, test the treated water too

A treatment system changes the question from "what's in my well?" to "is my system still doing its job?" EPA's WaterSense program notes that all treatment systems need ongoing maintenance, that unmaintained systems can make water quality worse, and that periodic testing helps confirm a system is working.^[source]

• Test the raw well water on the NC DHHS schedule, so you know if the source changes.
• Test the treated water for whatever the system is meant to address, such as arsenic after a reverse osmosis system or bacteria after UV disinfection.
• Retest after a cartridge, media or lamp change if results have been close to a limit.

Our Care Plans bundle scheduled maintenance with an annual retest, so the testing doesn't depend on remembering.

Where to get your well tested

NC DHHS says private well water can be tested through the North Carolina State Laboratory of Public Health, arranged through your local health department, or through a state-certified commercial lab. Procedures, fees and ordinances vary by county, so start with your county's environmental health program.^[source]

1. Step 1

   Pick the panel

   Match the test to the schedule above, plus anything a trigger calls for. A certified-lab panel through our water testing service can combine several.

2. Step 2

   Collect it correctly

   Use the lab's bottles and instructions. Bacteria samples in particular need sterile handling and fast delivery.

3. Step 3

   Read it against the limits

   Our guide to reading an NC well test explains units and limits.

4. Step 4

   Write down the date

   Keep results together so you can see trends and know when the next test is due.