Cross Connection Control (Backflow Prevention) Program

As required by the Illinois Environmental Protection Agency and the Department of Public Health, Every drinking water system in Illinois must have a cross connection control program, more commonly known as a backflow prevention program. Backflow prevention is designed to protect the public water supply from contamination from non-drinkable sources. For this reason, the Village of Deerfield created a cross connection control program with the goal of ensuring the quality of Village supplied water and protecting water customers. 

The Village of Deerfield has contracted with Backflow Solutions, Inc. (BSI) to manage the Village's backflow inspection program. BSI has experience managing similar programs for municipalities across the Chicagoland area. BSI will serve as the primary point of contact for backflow inspections within the Village and can be contacted at (800) 414-4990 or through their website at

Water customers with previously registered backflow devices will receive a notification and reminder directly from BSI Online that testing is due. The customer is free to choose any licensed backflow tester they want. Once the annual inspection is complete, the licensed tester will enter that information directly into BSI’s online reporting system. While BSI does not perform the backflow tests, they do have a comprehensive list of certified contractors that can be requested by contacting them. 

For residents that do not use their sprinkler systems and do not want to continue paying for annual backflow testing, the Public Works and Engineering Department offers a backflow prevention lock program. The lock can be installed on the water shut-off valve that supplies the sprinkler system. The device costs $45 to have installed and has a annual $25 re-inspection fee that begins the second calendar year that the device is installed. To sign up for the program please print out and sign the lock agreement form and return it to the Public Works and Engineering Department at 465 Elm Street with a $45 check written to the Village of Deerfield. 

For more information regarding the Village's Cross Connection Control Program, please contact the Public Works and Engineering Department at  (847) 317-7245. 

Frequently Asked Questions (FAQs)

What is a Cross Connection?

Any real of potential connection between the water supply and a source that can contaminate or pollute that water is considered a cross connection. 

Common Cross Connections include:

  • Commercial properties - from carbonated beverage machines and ice-makers, fire sprinkler systems and x-ray machines.
  • Residential properties - with lawn irrigation, fire sprinkler systems and even a common garden hose, when submerged in water.

What is Backflow?

When the system experiences a loss in water pressure, such as when a fire hydrant is opened or a water main breaks, a backflow can occur that causes water in the pipes to flow in the opposite direction.  That's when a contaminant or pollutant could travel into drinking water.

How will i know when my device is due for testing?

Backflow Solutions, Inc. will send you a letter thirty days before your device is due for its annual test. This letter will include a unique Customer Confirmation number that your testing contractor will use to register your test results. 

Does my backflow device still need to be tested if I no longer use my sprinkler system?

The State of Illinois requires that backflow device are tested annually whether or not the system is still in use. 
Does Backflow Solutions, Inc. perform backflow testing?

No, BSI is not permitted to do any testing. However, they do maintain a list of contractors in the area that can be obtained by contacting them at (800) 414-4990.

Do I send my test report to Backflow Solutions, Inc. from now on?

No, your backflow testing contractor will submit your test results for you.

Who do I contact for more information?

Please contact the Public Works and Engineering Department at (847) 317-7245.