Marana Water News: Pressure Reducing Valves

Some homes in the Marana Water service area have special devices installed known as Pressure Reducing Valves (PRV). These devices, as the title suggests, reduce the water pressure at the point of installation. 

Water pressure is used to ensure water can move reliably through the system across the various elevations, to provide fire flow, and to prevent cross-contamination. Pressures throughout the system are managed by Booster Stations or by gravity storage, which work to keep the system pressure between 40 and 80 pounds per square inch (PSI). Each of the water systems have their own set of booster stations working to regulate the water pressure. Additionally, the service area is divided into pressure zones based on elevation. These zones help to provide consistent pressure across the whole system. 

 Samples of a Pressure Reducing Valves (PRV)

Samples of a Pressure Reducing Valves (PRV)

Per the building code, any time the static pressure to a building is over 80 PSI, a PRV is required. Static pressure is the water pressure in the lines when no fixtures are turned on in the building, and can vary at different elevations. Typically, at lower elevations the static pressure is higher. It can be thought of as the weight of the water above that specific point from where the water leaves the booster station. There are some points in the Marana Water system where, due to topography, gravity may cause the pressure to exceed 80 PSI.

 PRV installed on a home

PRV installed on a home

The intention of a PRV is to reduce the pressure coming into a home to approximately 60 PSI. This can prevent damage to internal fittings, joints, and faucets. These devices are typically installed where the main water supply comes into the home, and have a slight bell shape. The photos to the left show examples of what a PRV might look like if there is one installed on a home.

Should a customer choose to install a PRV, Marana Water recommends having the work completed by a licensed plumber. If a PRV is already on the home, it is important to maintain it properly. A non-functioning device can reduce the pressure inside your home. Overtime, due to the hardness of the water, deposits can build up and cause the device to malfunction. A table of Marana Water's hardness can be found here.

 Close up of a PRV installed on a home

Close up of a PRV installed on a home

Marana Water is committed to providing the water reliability customers have come to expect. Keeping the water pressure at appropriate and safe levels is one of the duties of the Marana Water team. This dedicated group of employees monitor the booster stations and pressure in the lines.

If you have questions regarding the pressure in your area, or about PRVs in general, do not hesitate to contact our office at (520) 382-2570.