If you own a house or a business in the United States, you might have heard of backflow testing. In many regions, people are required to do annual testing of a plumbing component called a backflow preventer.
If you’ve received a notice to send your testing results to the local government or water company and you are not exactly sure what it is and what you need to do, we have the answer to all your questions.
Below, we have explained what backflow testing is, why it is important, what’s involved in the testing process, and how much it costs. Let’s start with the basics.
Backflow testing is a process of inspecting backflow prevention components (such as atmospheric vacuum breakers and dual check valves) to ensure their integrity and correct functioning. These components prevent the water in your main water supply lines from flowing in a reverse direction.
Proper functioning backflow preventers protect clean water supplies from contaminated or dirty water due to backflow.
Table of Contents
What is Backflow Testing?
First, we need to understand what backflow is.
The water distribution system in our home contains two types of pipes — one that brings clean drinking water in and one that carries waste out of the house. In both cases, the water is supposed to flow in one direction — either into or out of your home.
Sometimes, the direction of water flow is reversed, especially in situations like
- when pipes freeze
- pump breaks
- local public sources like fire hydrants use extensive water during an emergency event
The water is pumped into homes at a specific pressure. In such cases, the pressure level decreases, allowing water to flow in the opposite direction. This is called backflow. And when this happens, polluted water from the ground, storage, or other sources can enter your home pipes.
In simple terms, the reduced pressure levels disrupt the normal flow in the water system, causing polluted water to flow out through the clean pipes rather than through the waste pipes as it should.
To make sure this doesn’t happen, backflow prevention devices are installed in water systems. They allow water to flow in only one direction, safeguarding against contamination of water.
However, installing a backflow preventer isn’t enough. You must regularly test and maintain these devices to ensure they function properly.
Backflow testing is a standard process used to inspect the plumbing system (including all connected backflow devices) to make sure that water flows in one direction and is not contaminated by pollutants infiltrating the water supply.
A properly-working backflow prevention device won’t allow water to flow in both directions, even when pipes experience an unexpected drop in pressure levels due to bursting, freezing, or irregular high demand on the water supply.
Why is it important?
Intentionally letting backflow preventer devices fail or ignoring them will not only set you up for hefty fines (of up to $3,000) but also some serious illnesses and property damages down the line. There are several good reasons to perform backflow testing —
If a backflow preventer doesn’t work properly, clean water can be contaminated by solids, liquids, or gases entering the water supply. The dirty water may come from damaged pipes of water storage tanks, swimming pools, or sewer systems.
Imagine the health impacts of chemicals and pollutants in sewer systems and other dirty water regions when they reach your faucets. Your family members may suffer fever, stomach ache, vomiting, and diarrhea.
Avoid structural damage
When water travels in the opposite direction at high speeds, it puts more pressure on the wall and surrounding structures. If it happens more frequently, you may see corrosion, moisture, and other types of damage.
Thus, periodic backflow testing is important to keep your building intact and moisture-free.
Without a properly functioning backflow prevention device, your neighbors might suffer from water-borne diseases, such as bacterial gastroenteritis and amoebiasis.
This is why many state governments enforce strict testing compliance and impose heavy fines on violators. Some authorities have made it necessary to have a backflow prevention plan in every district.
Polluted water not only harms you or your neighbors, but it also disrupts the ecological balance. When contaminants get into the water supply, they re-enter the environment — dirty water goes back into the sewer, ultimately making its way to lakes and oceans.
The lakes are already polluted; you wouldn’t want to make it worse by putting contaminated water into these water bodies.
The bottom line is you can reduce water pollution by getting backflow preventers checked regularly.
What is a backflow preventer, and how does it work?
Typically, a backflow preventer is a check valve component installed on a piping system. It automatically opens and closes the valve, eliminating the possibility of water flowing in the opposite direction.
The other way to prevent backflow is to create an air gap (an open vertical space). The air gap can be created between any component that connects to the plumbing system (such as a faucet or valve) and any spot where polluted water can pool. This is the simplest and most reliable method because it doesn’t contain any moving part except flowing water.
In several countries, it is compulsory to install a backflow prevention system in every district. It must be tested when installed or relocated as well as on a regular basis.
When and how to book a backflow test?
Like all other mechanical components, backflow preventers won’t last forever. Their lifespan depends on several factors, such as water pressure, water quality, the external environment, and how often the device is used.
Nearly 5% of the backflow preventers that are tested fail. The failure usually arises due to a broken spring or a faulty O-ring that needs to be replaced.
Building managers and household heads are required to test backflow preventers every year. However, it is recommended to book a plumbing service when you experience any of the following things —
- A strong sulfur water smell
- Dust particles or sediments in the water
- Irregular water flow
- Discolored water
- Change is water taste
You can book the service by contacting a plumber or an HVAC contractor with a backflow testing license. Experienced, licensed, and insured plumbers are available 24/7 in most areas.
Many providers offer emergency plumbing services like sink installation, sump pump installation, drain cleaning, garbage disposal repair, gas line replacement, and water heater repair.
What’s involved in the testing process?
During a test, a certified technician determines whether your backflow preventers are up to code and conducts a test to see if the plumbing system is experiencing any backflow. The testing process usually involves closing valves and monitoring changes in gauge movement, water leaks, or other obvious signs.
Since the technician needs to monitor pressure levels in the plumbing system, he will shut off the main water supply for about 30-40 minutes. If your building has multiple backflow preventers, he will need to test each device. You won’t have running water during the entire testing process.
In most cases, technicians follow a checklist that includes a series of tasks like
- Verify valves prevent backflow
- Verify air-ports open when they should
- Verify relief valves open at specified pressure levels
If any component fails, the technician repairs or replaces it and runs a subsequent test to check the whole device.
Once the test is completed, the backflow inspection report is submitted to the local authority. The authority then reviews and approves the report and eventually sends a stamped copy for your records.
How much does backflow testing cost?
While most commercial backflow assembly tests cost between $50 and $200, the prices may vary depending on numerous factors, such as location, accessibility, the type of backflow prevention devices being tested, test failures, the company performing the tests, and additional services.
The cost of backflow tests may seem like an additional expense, but it ultimately saves more money by preventing damage to your water supply systems and ensuring that you drink uncontaminated water.
Plus, if you skip or miss the annual testing procedure, local authorities will impose a heavy fine of up to $3,000. In the worst case, they will cut off your water supply.
More to Know
A list of backflow prevention components and assemblies
A backflow prevention system can be made of several different (independent) devices. For example,
- Check valve is a two-port valve; one for water to enter and the other for water to leave.
- Double check valve contains two check valves assembled in series. It is designed to prevent back pressure and back siphonage.
- Chemigation valve is used in the agricultural sector to protect water supplies from chemicals.
- Reduced pressure zone device prevents back pressure and back siphonage. They are more reliable and testable to verify correct operation.
- Vacuum breaker is usually installed on a bibcock valve and urinal flush valve to prevent water from being siphoned back into the freshwater supplies.
- Air gap is the unobstructed vertical empty space between drinking water and the nonpotable point of use. It is the simplest form of backflow prevention system.
Backflow Preventers Market Size
The global backflow preventers market size is expected to reach $2 billion by 2030, growing at a CAGR of 4.5% from 2023 to 2030. This includes backflow prevention devices used in residential, commercial, and industrial places.
The key factors behind this growth include the strict government regulations regarding potable water, increasing demand for safe drinking water, and growing awareness about the importance of backflow prevention devices.