Backflow Preventer Installation & Repair

Backflow preventers protect your family’s drinking water from contamination. Southside Plumbing installs, repairs, and tests residential backflow devices throughout South Metro Denver.

PROTECTING YOUR WATER

What Is Backflow — and Why Should You Care?

Backflow is the unwanted reversal of water flow in your plumbing system. Normally, water pressure keeps water moving in one direction — from the municipal supply into your home. But when that pressure drops suddenly, water can reverse direction and pull contaminated water backward into your clean drinking supply.

What causes that pressure drop? A water main break in your neighborhood, heavy fire hydrant use, or even a significant pressure imbalance in your own system. When it happens, water from your irrigation system — which may contain fertilizers, pesticides, soil, and bacteria — can be pulled back through the supply line and into the same pipes that feed your kitchen faucet and showers.

A backflow preventer is a mechanical device that stops this from happening. It’s installed at the point where your potable water supply connects to a potential contamination source (like your sprinkler system), and it automatically closes when it detects reverse flow. It protects your family’s drinking water and prevents contamination from reaching the municipal water system that serves your entire neighborhood.

How Backflow Happens

Normal operation: Municipal water pressure pushes clean water into your home and through your irrigation system.

Pressure drops: A water main break, heavy hydrant use, or system imbalance causes a sudden drop in supply pressure.

Reverse flow: Without a backflow preventer, contaminated water from irrigation lines, pools, or other outdoor sources is pulled back into your potable supply.

Backflow preventer activates: The device detects the reversal and automatically closes, blocking contaminated water from entering your clean supply.

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IS IT REQUIRED?

Does Your Home Need a Backflow Preventer?

If your home has any of the following systems or features, a backflow preventer is most likely required by code — and is essential for protecting your water quality.

Irrigation / Lawn Sprinkler System

The most common reason for backflow preventer installation. Your sprinkler lines are underground, exposed to soil, fertilizers, and pesticides — all potential contaminants that can be pulled back into your water supply.

Pond or Water Feature

Decorative ponds and water features can harbor algae, bacteria, and organic debris. Any connection to your potable supply requires backflow protection.

Swimming Pool

Pool water contains chlorine, algaecide, body oils, and bacteria. A backflow preventer ensures none of this can enter your potable water supply if pressure drops.

WHAT WE DO

Backflow Preventer Services

From new installations to annual testing, our licensed plumbers handle every aspect of residential backflow prevention.

  • New Installation – We install backflow preventers for new irrigation system connections, pools, ponds, and fire suppression systems. Every installation meets Colorado plumbing code requirements and is performed by a licensed master plumber.
  • Repair & Rebuilds – Failed test? Leaking relief valve? Freeze damage? We repair and rebuild backflow preventers — replacing internal check valves, seals, and damaged components to restore full function and compliance.
  • Freeze Damage Repair – Backflow preventers are exposed to Colorado’s harsh winters and are a common freeze casualty. We repair or replace freeze-damaged devices and the copper and brass supply piping connected to them.
  • Replacement – When a backflow preventer is too damaged to repair or has reached the end of its service life, we replace the entire assembly. We match the correct device type and size to your system and ensure a clean, code-compliant installation.
  • Winterization Support – We help homeowners prepare their backflow preventers for winter, including draining the device and ensuring the supply line is properly cleared. Proper winterization is the best defense against costly freeze damage in Colorado.

WARNING SIGNS

Signs Your Backflow Preventer Needs Attention

A failing backflow preventer puts your family’s drinking water at risk. Watch for these signs that your device may need repair or replacement — and don’t wait to have it inspected.

Visible Leaking

Water dripping or pooling around the device body, connections, or relief valve ports is a clear sign that internal seals or check valves have failed.

Continuous Draining from Test Ports

Water running steadily from the test ports indicates a check valve is not seating properly and the device is not providing full protection.

Failed Test

If your backflow test comes back as failed, the device needs repair or replacement before it can be recertified. This is not something to postpone.

Discolored or Odd-Tasting Water

Unusual color, taste, or odor in your tap water could indicate that contaminated water has entered your potable supply — a sign of backflow failure.

Visible Freeze Damage or Cracking

After a hard winter, inspect the backflow device for cracks, splits, or deformation. Freeze damage is one of the most common causes of failure in Colorado.

Low Irrigation Pressure

Reduced water pressure to your sprinkler system can mean the backflow device is partially blocked, damaged, or not opening fully.

Need a Backflow Preventer Installed or Repaired?

Schedule with Southside Plumbing today!