Private well owners should test their well for bacteria and nitrates on a yearly basis. Residents whose water is provided by a community source, such as a subdivision, or municipal well supplier (e.g., Barrington and Tower Lakes) do not need to test individually since the supplier is required to perform tests regularly.

BACOG facilitates Bacteria and Nitrates testing for residents in the Barrington Area at an annual event at reduced costs and increased convenience:

The Annual BACOG Private Well Water Testing Event will be held Wednesday, October 11, 2023, 11:00am – 6:30pm at The Barrington Area Library.

Purchase water testing kits from October 2 – 10 at your local Village/Township Office. The full list includes: BACOG Office, Barrington Hills Village Hall, Barrington Township Office, Deer Park Village Hall, Lake Barrington Village Hall, South Barrington Village Hall and Tower Lakes Village Hall during regular office hours. Households with private wells are advised to test for bacteria and nitrates on an annual basis to detect these invisible, odorless contaminants. Bacteria and nitrates can result from animal, insect or human waste or fertilizers reaching the well water and can cause illness in humans.

On October 11, residents may drop off their water sample kits off at the BACOG Event at the Barrington Area Library anytime between 11:00am and 6:30pm. Follow the signs to the community room on the left right inside the main entrance. Although primarily a drop-off event, several of our Community Partners will be there with information and take-aways, along with the Lake County Health Department Staff, who will be available to residents for water testing questions. Test results will be emailed to homeowners within two weeks. Any homeowner with positive results for bacteria or elevated nitrate levels will be contacted within 48 hours by the Lake County Health Department.



Residents also have the option to test their water for bacteria and nitrates throughout the year at the following public health departments:

Cook County Public Health (847) 818-2841 (bacteria testing only)
To obtain a water testing kit from the Cook County Public Health Department,  contact their office in Rolling Meadows to schedule an appointment for pick up.  Residents will be responsible for mailing the test kit and paperwork to the IDPH lab in Chicago.

Lake County Health Department: (847) 377-8020 (bacteria and nitrates testing)
To obtain a water testing kit from the Lake County Health Department, stop by their office in Libertyville or pick one up at one of the following participating locations below.  Residents will be responsible for delivering the test kit to their lab in Libertyville.

    • Village of Barrington Hills (847) 551-3000
    • Village of Deer Park (847) 726-1648
    • Village of Lake Barrington (847) 681-6010


Residents rely on the water that comes into their home every day, and it is up to each private well owner to maintain its quality and safety.  Additional testing may identify contaminants in the natural well water before it is treated by a water softener or reverse osmosis (RO) system. Testing is recommended every 5 years or with a transfer of real estate.

The Barrington Area Council of Governments (BACOG) refers residents to the Illinois State Water Survey (ISWS) to test your natural water quality.  If a resident would like additional information about additional well water testing, contact the Illinois State Water Survey.