Backflow Prevention

💧 Purpose and Background: Protecting the City's Drinking Water

The U.S. Environmental Protection Agency (EPA) sets standards for Ground Water and Drinking Water safety. Local water suppliers, including our City, are responsible for maintaining clean, safe, and uncontaminated drinking water. One key requirement is to prevent contaminated water from flowing back into the City’s water distribution system.


🔄 What Is Backflow?

Water in the City’s distribution system is normally kept under pressure to flow safely to your home or business (e.g., through faucets, showers, irrigation systems). However, when that pressure drops - such as when water mains break, pipes crack, faucets are left open, or there is high water demand in another part of the system - contaminated water from outside sources can be pulled back into the clean water supply. This reverse flow is called backflow.

There are two main types of backflow:

  • Back-siphonage: Caused by a sudden drop in pressure in the main system.
  • Back pressure: Occurs when equipment connected to the system (like pumps or boilers) generates more pressure than the City’s supply, pushing water back into the system.

 


🛡 Why Backflow Prevention Matters

To protect our public water supply from contamination, all customers are required to install backflow prevention devices where their property connects to the City’s water system - usually near the water meter.

This is required by:

 

These devices must be installed at the customer’s expense and are a critical part of keeping our community's drinking water safe.


🧰 Types of Backflow Prevention Devices

Different types of backflow prevention devices offer varying levels of protection based on the potential risk at a given location or usage type. Types of devices include:

  • Air Gap
  • Atmospheric Vacuum Breaker (AVB)
  • Pressure Vacuum Breaker (PVB)
  • Double Check Valve (DCV)
  • Double Check Valve Detector (DCVD)
  • Reduced Pressure Zone (RPZ)
  • Reduced Pressure Zone Detector (RPZD)

Most Common Devices:

  • DCV – Typically used for residential water connections.
  • PVB – Commonly used for irrigation systems.


🔁 Testing & Permitting Requirements

All new and replacement backflow devices must be tested and inspected upon installation. To ensure continued protection of the water system, backflow prevention devices must be tested annually by a certified backflow tester (available through most plumbing contractors).

Customer Responsibilities:

  • Install devices as required by code.
  • Test annually (except for non-testable dual check valves).
  • Submit results to the City’s backflow administrator via BSI Online.
  • Obtain a plumbing permit for new installations or device replacements.
    • (Note: Re-certification does not require a permit.)

For details on the testing process, please visit the Backflow Assembly Tests Fact Sheet.