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Chesterfield County Utilities offers a residential companion meter that will charge for water consumption only, as opposed to both water and sewer. We are often asked by customers that live in Chesterfield County about companion meters. Over the years, Richmond Irrigation has obtained hundreds of companion meters and connected them to residential irrigation systems – so we have the answers!

Obtaining a companion meter and getting it connected to your irrigation system can be somewhat of a challenge, as there are multiple steps. We prefer to handle the entire process for our customers, but if you are interested in knowing what all is involved read on.

1. We obtain a plumbing permit for the backflow prevention device from Chesterfield County Department of Building Inspection.
2. Next, we complete an application for a companion meter and pay the fee – this is done at Chesterfield County Utilities.
3. After paying the meter application fee, Chesterfield County Utilities will come out to your property and physically install a second meter (usually next to your home’s domestic meter, see picture) – usually within 45 days of the application fee being paid.
4. Once the meter has been installed, the irrigation system must be connected to the newly installed meter. The piping between the new meter and the backflow prevention device must be inspected prior to being backfilled. Chesterfield County Department of Building Inspection will perform the inspection and once approved they will close out the plumbing permit (from step 1)
   • This step is very labor intensive, as the piping between the new meter and the backflow prevention device must be installed at a depth of 24”. If your backflow prevention device is located at your home’s foundation or in the crawlspace, significant labor is required to perform this work – as the bulk of it must be hand-dug to minimize disruption to the lawn and avoid damaging existing utilities.
5. After the inspection has been approved, we return to the property and backfill/compact the ditches.
6. Lastly, we test the backflow prevention device and submit the report to Chesterfield County Utilities.

The total cost of installing a companion meter, including all the county fees and the labor to connect the new meter to your existing system, ranges from $1,000 for systems with existing backflow prevention devices located near the meter to $2,000 for systems that require extensive labor to get piping from the new meter to the existing backflow prevention device.

We are often asked “How long will it take to recover my initial investment?” This will obviously vary depending on the cost associated with installing the meter, along with the size of your property. A good rule of thumb is if you are planning on owning the home for the next four years – you will likely come out even or ahead during that time.

How To Winterize Irrigation Backflow Prevention Devices

The backflow prevention device is the most important (and most expensive) component of a home’s irrigation system.

There are two types approved for use on irrigation systems in Virginia, the RPZ and the PVB. Both devices are highly susceptible to freeze damage, as they are installed above ground which typically makes them the first component or an irrigation system to sustain freeze damage. In order to minimize costs associated with repair or replacement of the irrigation system’s backflow prevention device, it is important to properly winterize. Richmond Irrigation always follows the manufacturer recommendations when servicing your home’s irrigation system. After properly winterizing an irrigation system by turning off the water and blowing out the lines with high volume, low pressure air – all the valves (ball valves and test ports) on a backflow prevention device should be left in a 45° (half open) position. Each manufacturer of backflow prevention devices specifies this procedure – see below for snips from product literature.

Winterization Procedure for Irrigation Backflow Prevention Devices

In order to follow the manufacturer recommendations for winterization, the ball valves and test ports of a backflow prevention device will be turned to the 45° position (half open position) and remain as such until spring startup.

On a PVB backflow prevention device there will be two ball valves and two test ports turned to the 45° position. To properly setup an RPZ backflow prevention device for the winter months, there will be two ball valves and four test ports turned at 45°. Again, this is the half open position – so it is important to return these valves to the normal position prior to spring startup. See the pictures (left) for more information. The RPZ backflow prevention device pictured to the far left is properly setup for the winter months, two ball valves and four test ports turned to the half open position (45°). The picture to the right shows an RPZ that is now ready for the water to be turned back on for the spring, two ball valves turned to the fully open position and four test ports turned to the fully closed position.

Most backflow prevention devices for irrigation systems in Richmond are installed on pvc piping with unions. The unions allow the backflow prevention device to be easily removed (without cutting pipe) for service. These unions are typically left in a ‘loose’ position over the winter months. Prior to turning the water back on for the spring startup, the o-rings of the unions need to be inspected and replaced if needed. Once verifying the o-rings are properly installed, the unions must be hand-tightened.

The pictures below show how a union allows the backflow prevention device to be easily removed from the pvc piping by simply unthreading it. You can also see the o-ring of the union that must be checked and replaced (if needed).

If requested, Richmond Irrigation will remove your backflow prevention device so you can safely store it in a heated environment over the winter months. However, we do not recommend this as it is not necessary to prevent freeze damage and it also allows for dirt/debris to possibly enter your system.

What Type of Backflow Prevention Device Do I Have?

Backflow prevention devices are the most important (and most expensive) component of an irrigation system. These devices protect the drinking water by preventing possible contaminants that can commonly be found in a lawn (pesticides, pet waste, etc.) from entering your home’s water supply.

There are two types of backflow prevention devices approved for use on irrigation systems in Virginia – the PVB (pressure vacuum breaker) and the RPZ (reduced pressure zone). Both devices are effective in keeping your home’s water supply safe from possible contaminants provided they are installed properly and routinely tested (annually).

Both devices are installed above ground and are usually located near the irrigation system’s main shut-off valve, as the device needs to be upstream of all irrigation components. Because the device is located above ground and can be an eyesore, we try to install it in a location that minimizes its visibility. A great location to install a backflow prevention device is a plant bed or along the side of a home’s foundation with other equipment, such as the A/C units.

Backflow prevention devices are sized based on the pipe size of the inlet/outlet of the device, which is determined by the flow requirements of the irrigation system. Most residential properties in Richmond have either a ¾” or 1” device. The size of a device does not dramatically change its appearance until you get into the larger sizes, which wouldn’t be found on a residential property. Commercial properties will commonly have the larger devices, 1-½” and greater. There are several popular manufacturers of backflow prevention devices — Wilkins, Febco, Apollo, Watts, and more – with Wilkins overwhelmingly being the most popular in the Richmond market. When installing an RPZ backflow prevention device, Richmond Irrigation’s first choice is the Wilkins 975XL. Our choice for a PVB backflow prevention device is the Wilkins 720A pressure vacuum breaker assembly. These devices will provide years of dependable service provided they are properly winterized prior to being exposed to freezing temperatures. For more information about the difference between the two types of backflow prevention devices, please see below:

What is a PVB? (Pressure Vacuum Breaker, or PVB)

The PVB backflow prevention device only provides protection against back-siphonage, not backpressure. Therefore, it must be installed at an elevation 12” higher than the highest outlet. The outlets of an irrigation system would be the sprinkler heads. For example, if your property has significant elevation changes, you will need the PVB to be located on the highest elevation of your property – otherwise it is likely that sprinkler heads would be installed at a higher elevation. This device has two ball valves (typically with blue handles) installed in a ‘L pattern.’ The PVB has two test ports. The test ports are a small ball valve operated by a flat head screwdriver. The purpose of the ports is to allow a testing instrument to be connected to the device for its annual test.  The PVB will have a name plate that contains a serial number used to complete the backflow test report form.

What is an RPZ? (Reduced Pressure Zone, or RPZ)

The RPZ backflow prevention device provides protection against both back pressure and back-siphonage. This allows it to be installed at any location/elevation of a property – which also makes it a much more expensive option. Most properties in Richmond have enough elevation change to mandate the use of the RPZ backflow prevention device. This device has two ball valves (typically with blue handles) installed ‘in line’. The RPZ backflow prevention device has four test ports – used to connect the testing equipment to the device for its annual test. The RPZ device will also have a name plate that contains a serial number that is used to complete the backflow test report form.

Do I Have a PVB or RPZ Backflow Prevention Device?

In summary, both devices perform the same task of protecting the water supply from possible contaminants. For the PVB to perform this task it must be installed higher than the highest sprinkler whereas an RPZ can accomplish this task regardless of the elevation it is located. Both the RPZ and the PVB are required to be tested annually to verify the internal components are functioning as designed. Both devices are installed on above ground piping (typically pvc) and the device itself is constructed from brass. The best way to distinguish between the two devices is to count the number of test ports. A PVB backflow prevention device has two test ports whereas an RPZ backflow prevention device has four. The picture shown to the left depicts a testing instrument connected to two of the four test ports of an RPZ backflow prevention device. Both devices will have two ball valves, one on the inlet side and one on the outlet side – however the orientation of the valves is different between the two devices. The orientation of the PVB’s ball valves are in a ‘L pattern’ whereas a RPZ’s ball valves are installed ‘in-line’.

Lastly, while it is useful to understand what type of backflow prevention device you have and its role in protecting the water supply – your best bet is to use a trusted professional when working on this device.

One of the most common questions we are asked is “How long should I water?”

While many companies might give you a recommendation of 15 minutes per zone on Monday, Wednesday, and Friday – Richmond Irrigation likes to consider more factors when setting up a watering schedule.

The truth is the amount of water that is required varies from month to month – if you setup your controller in the spring and don’t adjust it throughout the year, you are likely overwatering during the spring and fall months and underwatering during the summer months. To properly water a lawn in the Richmond area, you should at minimum adjust the watering schedule on a monthly basis. We understand that most folks with irrigation systems don’t have time to deal with this (we also understand that most controllers are not user friendly) – so we offer an Enhanced Maintenance Agreement that includes monthly visits during the growing season to adjust the watering schedule and review the system for any issues.

Our goal when setting up a watering schedule is to replace the amount of water that is being lost – water is lost through evaporation and transpiration (evapotranspiration). The rate that water is being lost changes dramatically throughout the year – see below table for historical data.