Water Quality Testing for Wells

Contaminants in drinking water can harm everyone’s health. Some can cause short-term health problems while others can cause long-term health problems. As a well owner, you can protect your family’s health by testing your water regularly. 

How often should I test my well water?

Wells are required to be tested for coliform bacteria when installed or repaired in Michigan. It is the property owner’s responsibility to collect the appropriate samples, as specified on your permit. As an alternative, you may contract the water well drilling contractor or home builder to collect the samples on your behalf.

The Michigan Department of Health and Human Services (MDHHS) recommends the following routine well testing schedule.

Every 3 to 5 Years


Certified Drinking Water Labs in Livingston County:

Brighton Analytical
2105 Pless Drive
Brighton, MI 48116
(810) 229-7575

Water Tech
718 S. Michigan Ave
Howell, MI 48843
(517) 548-2505

For help interpreting your water sample results, visit Home - Be Well Informed.

Please review your issued permit for required testing. At a minimum, most new wells must be tested for:

  • Bacteria: Must be negative
  • Nitrates: Must be 10 parts per million (ppm) or less
  • Arsenic: Must be 10 parts per billion (ppb) or less

Packaging and shipping water samples: MDHHS Video about Thermal Preservation of Water Samples

PFAS Testing

PFAS are human-made chemicals that can persist in the environment for many, many years. See the image below showing how some PFAS sources contaminate the environment.

Learn more about what PFAS are, including potential health risks, and how you can protect yourself and your family. If you are on a private well, take a look at the PFAS in Drinking Water for private residential Well Owners Fact Sheet. If you live near a potential source or if you are unsure, consider testing your drinking water as a precaution. Call the MDHHS Environmental and Health Hotline at 800-648-6942 to see if your home is in an area that is under investigation for PFAS. They may be able to test your water for free. If they cannot test your water for free, contact a certified drinking water lab about PFAS testing and the test cost. They can help you get sample bottles and provide instructions on how to collect your water sample yourself. View labs that offer PFAS testing. Read more on home testing guidance for PFAS.

Home filters

If you have a private residential well, an in-home filtration system can help filter natural impurities (such as iron) and manmade contaminants (such as PFOS and PFOA).  Learn How to Choose a Filter

Avoiding PFAS in consumer products

You could also be exposed to PFAS from every-day household items such as carpeting, cosmetics, and cleaning products. Switching to PFAS-free products can reduce your daily exposure to PFAS and reduces the amount of PFAS entering the environment.

By using PFAS-free products, Michiganders can help protect the environment and send a message to companies that consumers no longer want products containing PFAS. Learn What to Look for

Visit Michigan PFAS Action Response Team (MPART) website to learn even more about Per- and Polyfluoroalkyl Substances (PFAS).

Lead & Copper Rule

The purpose of the Lead and Copper Rule  (LCR) is to protect public health by minimizing lead and copper levels in drinking water. Lead and copper enter drinking water mainly from corrosion of plumbing materials. The rule establishes action levels for lead and copper. An action level exceedance is not a violation but triggers other requirements to minimize exposure to lead and copper in drinking water, including water quality parameter monitoring, corrosion control treatment, source water monitoring/treatment, public education, and lead service line replacement. All community water supplies and non-transient noncommunity water supplies are subject to the LCR requirements.

Exposure to lead and copper may cause health problems ranging from stomach distress to brain damage.  Lead is toxic to everyone, but the impact on children can be devastating. It stunts brain and physical development; creates learning and behavioral problems; and damages organs. All of it can make it difficult for children to reach their potential at no fault of their own.

The Michigan Department of Health and Human Services updated their definition of an elevated blood lead level for children from 5 µg/dL to 3.5 µg/dL, following the Centers for Disease Control and Prevention updating their blood lead reference value (BLRV) in October 2021. For more information check out MDHHS’s Get Ahead of Lead webpage.


How do I test my well water for bacteria?

  • Obtain sample bottles from a Certified Drinking Water Laboratory.
  • When you are ready to sample, remove the aerator from the faucet, if possible. (If the aerator is difficult to remove, just leave it on). Dip the tip of the faucet into a small container of bleach for 30 seconds. Leave the bleach on the faucet for 5 minutes to kill any bacteria present.
  • After disinfection, turn on the cold water full stream and let it run for 15-20 minutes. While the water is running, remove the lid from the sample bottle. Do not touch the interior of the bottle or lid. Also, leave any pill or powder in the bottle! Turn the faucet down to a small stream and collect the sample. Fill the bottle up to the neck of the bottle (but don’t overflow!) and replace the lid.
  • Put the aerator back on the faucet.
  • Return the sample to Certified Drinking Water Laboratory.  It is best to collect the sample just before delivery to the lab. Samples should be refrigerated or chilled while stored or transported.
  • If you receive a notice that your sample is positive for bacteria, you may want to disinfect your well.

How do I disinfect (chlorinate) my well?

If your well water has tested positive for coliform bacteria, you may want to disinfect (chlorinate) your well.  Please read carefully and follow these instructions.
  • One cup granular chlorine or one gallon regular unscented liquid bleach
  • Clean hose(s) that extend from outside spigot to well
  • Wrenches to remove well cap
  • 5-gallon bucket
  • Small cup
  • Water sample bottle(s)
  • Location of ON/OFF switch for well pump
  • Eye and skin protection


  1. Draw off about four gallons of water into a 5-gallon bucket.
  2. Mix one gallon of regular unscented liquid bleach with the four gallons of water.
  3. Note: Liquid bleach should not be used with a steel well casing; it can break loose accumulated corrosion and cause pump failure. Instead, use granular chlorine in a steel well casing.
  4. Turn off the power to your well pump.
  5. Remove the well cap. Be careful if set screws or bolts on your well cap are rusty.
    • Note: If the well cap has one large bolt in the center of the cap, you should not attempt to remove it. Have a licensed well contractor disinfect your well. In addition, if your well head or top is buried, or if you have a shallow well installation, your well does not meet current well construction code requirements. Chlorinating these wells is difficult and in many cases impossible. If you have an unsafe water sample and you have a well that fits this description, contact Livingston County Environmental Health.
  6. Pour the chlorine/bleach mixture into the well between the casing and the cross bar or “T” bar. DO NOT pour the mixture into the 1” center hole. (Newer wells will often have markings or a statement next to the correct hole, indicating where to pour the chlorinating solution.)
  7. Avoid contact of the solution with the wire connections inside the well, as they could corrode.
  8. Connect a clean hose to an outside spigot and extend it into the well approximately four feet.
  9. Turn the power supply back on to the well pump.
  10. Turn on the outside spigot that is connected to the hose in the well. Allow the hose to run in the well for approximately 20 minutes. This distributes the disinfectant throughout the well system.
  11. Turn the spigot off when done.
  12. Turn off the power supply to the well pump. Once the power is off, remove the hose from the well, and put the well cap back onto the well using the existing nuts and bolts.
  13. Turn on the power to the well pump.
  14. All work is now completed on the wellhead. Now it’s time to distribute the chlorine/bleach to the pipes. Turn on each indoor and outdoor water faucet, and allow cold water to run until a chlorine/bleach odor is detected. Don’t forget to run the shower, clothes washer, dishwasher, and any outside hydrants or plumbing fixtures in other buildings. Also, flush each toilet a couple of times. Once you detect a bleach odor, turn off all faucets.
    • Note: Some water softening units should not be chlorinated. Contact your water softening company prior to disinfection to determine if you should bypass the softening system.
  15. Allow the solution to remain in the system for a minimum of eight hours, or overnight. During this time you should not drink, bathe, wash clothes, or cook with the water, but you can use it for toilet flushing.
  16. After the solution has remained in the system for a minimum of eight hours, connect a hose to an outside spigot and allow water to run onto the ground for 20-30 minutes to remove the chlorine solution from the water system. Try to keep the water away from your drainfield and any plants or trees if possible.
  17. After 20-30 minutes, turn off the spigot and then run each indoor and outdoor water faucet for 2-3 minutes to remove the solution that was in the pipes.
  18. It is now time to collect the water sample. Remove the screen or aerator from the faucet tip.
  19. Submerge the tip of the faucet into a small container of bleach for 30 seconds. Allow the bleach to remain on the faucet tip for five minutes. (This reduces the possibility of a false-positive sample reading, as the faucet tip is a potential area of bacterial growth.)
  20. Once the faucet tip has been disinfected, turn on the cold water and allow it to run for five minutes.
  21. While the water is still running, remove the lid from the sample bottle. DO NOT touch the interior of the lid or sample bottle, and remember that the pill or powder substance in the bottle must remain inside the bottle.
  22. Fill the bottle to approximately ½ inch from the top and replace the lid.
  23. Place the screen/aerator back on the faucet.
  24. We recommend that samples be refrigerated or chilled while stored or transported. If you receive a notice that your sample is positive for coliform bacteria, or if you have any questions regarding the well disinfection procedure, please contact Livingston County Environmental Health.

Disclaimer: This procedure is intended to be used for chlorinating 5-inch PVC wells with submersible well pumps. If your well has a jet pump (either shallow or deep), or if your casing is 4-inch steel or smaller, we advise that you consult with a licensed well driller prior to chlorination. These instructions are provided as public information based on conditions found in Livingston County. There is no implied guarantee and the procedure may have to be repeated. Livingston County accepts no responsibility for the outcome, or for any damage incurred.

For questions regarding well, soil evaluations, and/or septic systems, please call/email the assigned Environmental Health point of contact (based on your Township).

Last Modified March 1, 2024

Environmental Health
Livingston County Health Department Logo
Matt Bolang

Matt Bolang
Health Officer



(517) 546-9858


Monday – Friday
8:00 a.m. – 5:00 p.m.
Closed County Holidays


2300 E Grand River Ave
Suite 102
Howell, MI 48843


(517) 546-9853
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