What Is The Purpose Of A Backflow Preventer?

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We assume that the water in our plumbing system is clean and safe for consumption, but that may not always be the case. Did you know that if your backflow preventer is not functioning, your water may be contaminated with pesticides, harmful chemicals, or even sewerage?

Backflow preventers/devices are part of the plumbing system that go relatively unnoticed, that is until they malfunction. In 1990, the Florida Building Code mandated that all buildings with an irrigation system, are to be fitted with a backflow preventer, but what are these devices, and how do they work?

What Is A Backflow Preventer?

A backflow preventer is a mechanical device also known as a Reduced Pressure Zone Valve (RPZ Valve). Installed in the water pipe next to the meter, this device allows water to flow in one direction only and prevents any water from flowing in the opposite direction. A backflow preventer serves the vital function of protecting both your drinking water and the city’s water supply, from contamination.

Degrees of hazard vary between commercial and residential properties, so not all backflow devices are the same. A qualified plumbing technician will need to assess the degree of hazard of your home or business and advise on the appropriate backflow preventer, by taking the county’s environmental health regulations into account.

How Is Water Contaminated?

Water flowing in the wrong direction, contaminated with chemicals, pesticides, human waste, or food, poses a serious health risk. There are two main reasons that water will flow in the opposite direction, and both these reasons relate to the water pressure. Two water pressure shifts, known as backpressure and back siphonage occur if:

• There is increased water flow further down the water system
• There is a decreased flow in your home.

Back Pressure

Back Pressure forces water to flow in the opposite direction. This happens when the downstream pressure of a non-portable water source becomes greater than the pressure of the main water supply.

Back Siphonage

Negative pressure in the water line can cause a vacuum or partial vacuum, resulting in potentially contaminated water being pulled back into the clean water supply. This often occurs if there is a break in the mainline, or if there are construction or firefighting activities nearby.

Signs That Your Water May Be Contaminated

We all expect the water flowing from the faucet to be clean, a clear color, have a pleasant taste, and have no odor. Signs that your water may be contaminated include:

• Appears discolored. Be wary of the water if it is brown, yellow, or pink.
• Smells bad. Often contaminated water has a bad rotten egg/sulfur smell.
• Has visible particles (often rust) or contains sediment.
• Has a bad taste
• Contaminated water flow (out of the faucet) is often slow or interrupted.
• Contaminated water affects the drainage system. The water will either drain very slowly, or you may notice both increased and decreased pressure in different drains, simultaneously.

Where Are Backflow Preventers Fitted

Backflow preventers are installed wherever there are high-risk scenarios of backflow water potentially contaminating the main water supply. Normally fitted next to the water meters, these devices will be found on:

• Irrigation systems
• Buildings using reclaimed, pond or well water
• Commercial fire hydrant service lines
• Portable water lines
• On the water supply lines of businesses that use chemicals daily. These include:
  • Car Washes
  • Restaurants
  • Hair salons

When Must Backflow Preventers Be Maintained

Backflow preventers consist of many internal parts like:

• Internal springs,
• Seals,
• Test cocks,
• Shut-off valves, and
• Other moving parts

These all need to be tested and maintained annually to ensure that the device is functioning as it should. Other instances where backflow devices need testing and maintenance are:

• When they are initially installed
• If they are relocated
• If they are broken and need repair

​​Art Plumbing, Air Conditioning & Electric, South Florida’s Backflow Protector Specialists

Does your drinking water look cloudy or smell bad? Contaminated water poses a serious health risk and needs to be attended to urgently. Art Plumbing, Air Conditioning & Electric are South Florida’s plumbers of choice and are a phone call away. Call us at 1-800-475-1504 to inspect, maintain or replace your backflow preventer today.