Backflow System Basics for Your Yard’s Sprinklers

It’s not just the plants in a landscape that benefits from a well-designed irrigation system; people do, too. An efficient irrigation system isolates landscape water from drinking water to minimize disease outbreaks from contaminated water. For this reason, a backflow system must be installed on all irrigation systems. In addition, you should do annual backflow testing to ensure the integrity of your backflow system is fine.

What Does Backflow Mean?

As the name suggests, backflow happens when water flows oppositely into your water supply rather than out of it. When irrigation backflow occurs, contaminants from pesticides and other sources can contaminate your drinking water supply. As a result, you can accidentally ingest the fertilizer you intended for the garden.

What Situations Lead To Backflow?

There are two forms of backflow: back-siphonage and backpressure. Back-siphonage from sprinkler heads and the irrigation pipe system can introduce harmful substances like fertilizers, pesticides, and manures into the drinking water supply if the pressure in the main region water line suddenly drops. Similar contamination can occur with a sprinkler, spray nozzle, or pesticide sprayer linked to a garden hose. Therefore, the public’s health is seriously at risk from this. Reduction in pressure may be due to a line break or withdrawal of a lot of water, like during firefighting.

A lawn sprinkler pump or injector system might reintroduce pollutants to the drinking water supply if not installed correctly. Also, avoiding doing annual backflow testing is another contributor to the problem. In this instance, the pump creates a pressure higher than the pressure in the drinking water system; the process is known as backpressure backflow.

How Frequently Do Backflow Events Occur?

Backflow problems occasionally happen, even though you might not hear about them frequently. As a result of the backflow of toxic and poisonous substances, there have been several incidences of harm, sickness, and even death in the United States. The good news is that it’s not hard to keep your house, family, and drinking water safe. Even if a backflow system wasn’t built with your irrigation system, you might install one immediately to avoid contamination. You may also reduce contamination by annual backflow testing of your existing backflow system.

Why do You need to Install a Backflow System on Your Sprinkler System?

If the flow of water in your irrigation lines reverses for any reason—the chemicals in irrigation water, which include fertilizer and pesticide, might pollute your drinking water. Backflow pollution can pose a major health risk, leading to severe disease or, in the worst circumstances, death. By installing a backflow system, you can be sure that your drinking water will be safe from contamination by a flow reversal. Also, you can ensure that your system is in good condition every year by doing annual backflow testing.

Types of Backflow Systems Available

The sprinkler system valve unit is the backflow prevention device for most residential irrigation systems. It’s essential to take some time and think about your specific lawn irrigation system when selecting a backflow prevention device. Still, it would help if you didn’t let that stop you from making an informed decision. The three most often approved and utilized backflow devices include a pressure vacuum breaker, a double-check valve, and reduced pressure assemblies. Each of these three types of backflow preventer devices is put in an irrigation system to ensure the safety of the entire system. After each zone’s control valve, an atmospheric vacuum breaker is fitted as a typical fourth form of backflow system. You may learn all about these backflow systems by reading the following:

1. Pressure Vacuum Breaker

It is the most popular and least expensive form of whole-system backflow preventer. Therefore, Irrigation systems would be incomplete without a pressure vacuum breaker (PVB). It prevents the contamination of your home’s potable freshwater supply from the irrigation system backflow. The PVB is often outside, either adjacent to an external wall or in a ground-recessed box in sprinkler systems. Moreover, some systems feature PVBs inside, usually close to the irrigation system’s water cutoff in a crawl space or basement. You can mount it above the tallest part of the system, whether the sprinkler head or the steepest part of the yard. It has two main components a check valve and an air intake with an external vent (open-air). Normally, the check valve will let water through but will prevent air from entering the system. To avoid water backflow, the vented chamber opens when air pressure exceeds water pressure.

Extra information on Pressure Vacuum Breaker Assembly:

• Installation must be 12 inches above the system’s highest outlet.
• It should be used for irrigation without chemigation.
• Installation must be vertical, with the intake at the bottom.
• Only back-siphonage is prevented.
• Where there is a risk of backpressure, installation is not recommended.

2. Reduced Pressure Zone

The most complicated, most expensive, and most secure and dependable backflow prevention device is the reduced pressure zone. An RPZ is put explicitly on your plumbing system to safeguard your drinking water and the municipal water supply. It consists of an outlet shutoff valve, four test cocks, two separately working spring-loaded check valves, a relief valve, and an intake shutoff valve. In addition, these valves offer the most protection for your potable water. As a result, authorities and contractors across the country mandate the use of backflow protection devices in new construction. Therefore, annual backflow testing ensures that these parts of the backflow system function at maximum capacity.

The first check valve lowers the supply pressure such that there is always less pressure in the check valves than in the supply. Since the pressure in supply is always higher than in the zone, even a leaking upstream check cannot allow backflow to get through. In the event of backflow, an RPZ’s built-in relief valve will open and release the water. You can tell that the RPZ’s backflow preventer is functioning correctly if you approach it and see that no water is spilling from the relief valve.

There are several different configurations for reduced pressure zone assemblies. When installing underground, go with a straight or “inline” layout. If you want a small footprint for above-ground installation, consider using an “n” configuration assembly.

Extra information on Reduced Pressure Zone (RPZ):

• Above-ground or inline installation is possible, although above-ground installation is more appropriate.
• It can be used in combination with chemigation.
• They are installed where there is a risk of backsiphonage or backpressure.
• Unless otherwise specified by the factory, it must be mounted horizontally.

3. Double Check Valve

Installations below ground or inside buildings benefit from double-check valve (DCV). It has an input cutoff valve; two authorized, independently working spring-loaded check valves, an output shutoff valve, and four test cocks. Depending on regulations in your area, you may set up the double-check valve vertically and do an annual backflow testing every year.

When it comes to inline backflow prevention devices for underground lawn sprinkler systems, the DCVA is by far the most popular choice. Before moving on, verify with local authorities since specific local codes call for above-ground installation. This backflow system can be constructed from new parts, but it’s not recommended due to the possibility of noncompliance with local regulations. Therefore, buying a pre-assembled double-check valve is the most reliable, time-efficient, and financially sensible choice.

Extra information on Double Check Valve Assembly:

• Both above-ground and inline (underground) installations are possible.
• Installed either horizontally or vertically; however, horizontal installation is ideal.
• Should not be installed in an irrigation system that uses chemigation.
• Installed where there is a risk of backsiphonage or backpressure.

4. Atmospheric Vacuum Breaker (AVB)

When it comes to backflow protection for single- or dual-zone irrigation systems, AVB is the cheapest and most straightforward option. Furthermore, it is the least dependable and recommended option. Most urban and suburban areas do not permit AVB installation in lawn sprinkler systems. It cannot be utilized at constant pressure, when shutdown valves are downstream, where backpressure is possible, or on a chemigation system.

To stop backflow, an atmospheric vacuum breaker employs a check float. The pressure from the water moving forward forces the check-up out of the path of water, sealing the air gap. A backflow situation may develop when the pressure in one direction suddenly decreases or ceases. Then the check is released into the water stream, creating a pressure differential that prevents siphoning.

Extra information on Atmospheric Vacuum Breaker Assembly:

• It cannot be used with chemigation
• Back-siphonage can only stop if installed vertically with the lid on top.
• It cannot be installed in areas where there is a possibility of backpressure
• One unit is needed per zone and must be installed after the zone control valves.
• Avoid using it in situations where it will be continuously under pressure for longer than 12 hours because the disc float might stick, making it incapable of protecting the water supply. As a result, this is one important reason why annual backflow testing is a must for any backflow preventer.

What Is Annual Backflow Testing?

Annual backflow testing may be something you’ve heard of as a property or business owner. The backflow system on your St. Louis property must be checked and serviced regularly, and in many areas, this must be done every year. You may get a notice asking you to send test findings to the appropriate authorities or Water Company. However, as you continue reading the notice, your confusion over its contents and subsequent actions grow. Fortunately, Allen Outdoor Solutions are available to address any concerns or issues. Let’s define annual backflow testing and see why it’s crucial.

First, backflow system testing determines the existence of a backflow issue and its source. Standard testing procedures involve temporarily turning off your water supply. Hiring a professional company like Allen Outdoor Solutions to do backflow testing is essential for this and other reasons. Instead of you having to disconnect the water supply manually, we will do it for you. You should know that you can have your water service cut off permanently if you don’t perform annual backflow testing.

Our technician will coordinate a temporary water service shutoff on the day of your backflow testing. The technician will measure the pressure in your backflow system to ensure that your backflow system is working correctly. At the same time, our technician will perform a series of tests that include opening and closing the valves. Also, the technician will examine the valves for signs of leaking, gauge movement, and other malfunctions. The technician will ensure that the system correctly activates before concluding. If the valves are functioning properly, you won’t have any problems; otherwise, our technician can probably do some fast repairs to ensure that your drinking water will be clean and safe. After finishing, the technician from Allen Outdoor Solutions will restore your water service, complete the required documentation, and submit your findings directly. It should be noted that Missouri law requires you to have a licensed backflow testing company do your annual backflow testing.

The Importance of Annual Backflow Testing?

Annual backflow testing is essential to avoid its negative consequences. Here are a few advantages of backflow testing:

1. Preventing Exposure to Heavy Metals

Another type of contamination caused by backflow is heavy metals; this problem is more common in public places like restaurants, where carbonated water can dissolve the copper in soda dispensers, potentially exposing customers to copper poisoning. In addition, heavy metals used in metal plating, such as arsenic, chromium, or lead, may leak into water supplies, backflow, or otherwise endanger people’s health in their homes or commercial establishments.

2. Preventing Chemical Contamination

Through backflow, chemical wastes like herbicides, insecticides, and substances like sodium hydroxide can enter plumbing systems. Once these compounds get into the water supply, they pose serious health risks to humans.

3. Health Concerns

Annual backflow testing is important for many reasons, but health safety is at the top of the list. Pollutants in the sewage system can contaminate the water supply if water flows in the opposite direction. This pollution creates a serious health concern in the home environment since drinking dirty water is a real possibility.

4. Keeping the Community Healthy

Communities with backflow preventers tend to be healthier overall. If a society deals with dirty water, it will never flourish. Excessive dampness can cause some community members to become ill and buildings to fall apart. To avoid making the entire neighborhood sick, you should frequently examine your backflow prevention devices. Cities that don’t regularly inspect and maintain their backflow preventers may be subject to penalties.

Suppose you are in St Louis and need your landscape transformed into your dream garden. Contact Allen Outdoor Solutions, the leader in the landscaping business. We offer sprinkler installation and maintenance, outdoor lighting solutions, landscaping, snow removal, fencing, and lawn care. You dream about it, and we make it a reality.

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