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Information for Property Owners

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What is an RPZ and why do I need it tested?

RPZ stands for Reduced Pressure Zone Backflow Preventer and is installed on various plumbing systems to protect your drinking water and the City water supply from contaminates. An RPZ is a specific type of backflow prevention device that is used when a higher level of protection is needed. Even small fluctuations in City water mains can cause drops in pressure large enough to allow contaminants from a non-potable system to backflow into the potable drinking water supply.

The State of Illinois regulates the use of RPZs as outlined in the Illinois State Plumbing Code and by the Illinois Environmental Protection Agency. The law not only requires the use of RPZ devices, but also that the devices must be tested once per year. State law also requires that the local municipality provide oversight that all requirements are being met.

Is there a fee for having an RPZ?

Yes. There is an annual fee of $35 for each device. This fee will appear on your water bill once per year.

Is there a special requirement for hiring a contractor to work on my RPZ?

Yes. On September 26, 2011 the Evanston City Council provisionally adopted ordinance 50-O-11 requiring all those who install, repair, alter, remove, certify and test cross connection control devices within the boundaries of the City of Evanston to obtain a Cross Connection Control (C3) Contractor License. As of May 1, 2012 only City of Evanston Cross Connection Control Device Testing & Certification Reports submitted by a licensed C3 Contractor will be accepted by the City. Please verify that your contractor has obtained this license prior to completing any work.

How do I find a C3 Contractor?

The City of Evanston maintains a list of licensed C3 Contractors (see link below). If your contractor does not appear on this list, you may wish to contact them to determine if they have been recently licensed. There is no fee for a contractor to become licensed and contractors may be licensed at any time by submitting the appropriate application.

C3 Licensed Contractors Public List (updated 5/1/2019)

Are there special requirements for lawn irrigation systems?

Yes. All lawn irrigation systems must have a reduced pressure principle zone (RPZ) backflow prevention device, which must be installed and certified annually by a licensed C3 Contractor. This testing and certification must be completed between January 1 and May 15 of each year, and prior to the system going into service.

What if I don’t put my irrigation system into service until after May 15?

It is required by the City of Evanston that all irrigation systems be certified no later than May 15 even if the system is placed into service later in the season.

Are there other types of backflow prevention devices that can be used on a lawn irrigation system other than an RPZ?

No. Older systems may have had a different type of backflow prevention device installed. However, current regulations require that all lawn irrigation systems must use an RPZ.

What if I am not using my irrigation system this year? Do I still need to have the RPZ tested and certified?

Yes. Unless the lawn irrigation system is permanently abandoned, the RPZ must be tested and certified annually. The proper procedure for abandonment of an irrigation system is shown in the link below.

Proper Procedure for Abandonment of an Irrigation System