A backflow prevention assembly is a mechanical device that prevents water from flowing backwards. The common assembly types are a testable dual-check valve (DCV) and a Reduced Pressure Zone (RPZ) valve.
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Under normal conditions, water from the public water distribution system (the “public system”) flows into plumbing inside a home or business. When backflow occurs, the water flows from the plumbing in the home or business back into the public system.
Backflow occurs when the water pressure in the home or business is higher than the pressure in the public system. This condition can be caused by a drop in water pressure in the public system or by an internal home or business piping system that operates at higher pressures than that of the public system.
A cross-connection is a connection between the public system and a source of non-potable (not safe to drink or contaminated) water or other fluid. If such a connection is not properly controlled, and a backflow occurs, contaminants could make their way from a non-potable source into the public system. Because of the risk of contamination, such non-potable systems typically require the installation and proper maintenance of a backflow prevention assembly.
Examples of common cross connections are:
- Commercial kitchen equipment
- Commercial laundry equipment
- Fire suppression systems
- Lawn sprinkler systems
- Outdoor pools
Assemblies must be tested when installed and once a year thereafter.
Any plumber or plumbing contractor licensed through the Illinois Department of Public Health (IDPH), who is also a Certified Cross Connection Device Inspector (CCCDI), as recognized by the Illinois Environmental Protection Agency (IEPA), is acceptable.
The Village has hired BSI, Inc. (“BSI”) to manage the Village’s backflow inspection program, including maintaining the yearly inspection records. Due to the large number of assemblies in the Village, it is more efficient to have an outside contractor with a specialization in managing such systems, like BSI, to manage the program. BSI will contact registered assembly owners to inform them when the annual inspection is required.
To change the contact name or telephone number for a backflow prevention assembly, the water service customer or property owner should contact BSI at 800-414-4990.
The CCCDI, described above, is responsible for returning the original, signed test reports to BSI, either by regular mail or through an email attachment. The test reports must be submitted within five (5) calendar days of the test date. The CCCDI should provide the water customer with proof that the forms have been submitted to BSI as required.
If an assembly fails, it must be repaired or replaced. Replacement of an assembly requires a plumbing permit from the Village’s Community Development Department which can be contacted at 847-459-2620, and can only be done by a licensed Illinois plumber or plumbing contractor (Section 16.2.010 of the Village Code).
An application for a building/plumbing permit and a plumber letter of intent can be found at the following web addresses:
If assembly test results are not received by the required due date, the Village, through BSI, will send the water customer/property owner a second notice requiring testing within 30 days. If the water customer does not have the backflow prevention assembly tested, further enforcement actions will be undertaken, including:
No, the removal, replacement, or relocation of an existing backflow prevention assembly, requires a plumbing permit from the Community Development Department, and can only be performed by a licensed Illinois plumber or plumbing contractor.
.If you would like to synchronize the test due dates for several assemblies on numerous water meters, whether located inside the same building, or inside multiple buildings, or located on multiple properties, please contact BSI at 800-414-4990.
Most cross connections are observed by the Village during inspections associated building permits or business license applications, however, the Village also conducts periodic surveys to identify and eliminate possible sources of cross connections to help ensure the safety of the public water supply. The information collected through the surveys helps to identify where backflow prevention devices may be needed as well as providing information on existing devices that may not have been previously submitted to BSI.
It is the responsibility of the water customer or property owner to pay for the annual testing and any required repairs to the backflow device.
If you have any questions regarding the backflow prevention program, please call the Utility Division of the Public Works Department at 847-279-6920.
Backflow prevention is required by federal, state and local regulations, as summarized below: