RPZ Backflow Testing

(Reduced Pressure Zone) Device

An RPZ (reduced pressure zone) is a type of backflow device that protects drinking water in your residence and prevents contaminants from reaching the city water supply.

RPZ backflow testing is an annual city requirement.

Once the irrigation system is turned on, we recommend testing to be done in the spring.

The device must be tested before your system is shut off; otherwise, it cannot be examined.

Please notify us if you would like your RPZ backflow tested when we schedule your turn-on.

*Please Note: Testing is done at a separate time from your appointment.

Open & Operating

Valve handles are parallel to the pipes and the direction of water flow.

Closed & Shut-Off

Valve handles are perpendicular to the pipes and the direction of water flow.

How Does an RPZ Device Work?

The RPZ Device prevents back pressure and back siphonage (if reduced pressure exists in the supply piping, allowing undesirable substances to be drawn into the drinking water supply). Contaminants can enter an irrigation system from fertilizer or pesticides that are sprayed on lawns. If there is a water leak in the house, a house water service break, a city water main break, or a hydrant flushing, the water pressure can drop, causing systems to back up into the drinking water supply. If this occurs, the RPZ will open up and dump water out rather than allowing potentially contaminated water to backflow into the drinking water supply.

Received a Letter from Your Village?

Sometimes you may receive a letter from your village requiring your device to be tested. If you are unsure whether or not your backflow needs testing, please check with your city or village.

We do not control mandates.