Cross Connection 101

Background | What is a Cross-Connection? | Backflow Devices | Questions?

Background
The City of Brighton has been providing services to eliminate cross connections for commercial and industrial facilities since 1981. This program has proven to be effective in safeguarding our resident from questionable water quality issues due to backflow. Beginning in the fall of 2021, the water department will extend this program for residential properties. Two goals will be accomplished with this program. First, it will help to further protect the water distribution system against the entrance of contaminants. Secondly it will place the City of Brighton in compliance with the Department of Environment, Great Lakes, and Energy (EGLE) as mandated by Michigan’s Safe Drinking Water Act.

Residential Cross Connection program will consist of inspections and the testing of backflow devices. Inspections will be of the exterior of the property and focus on irrigation systems, pools, spas, hose bibs, and any other hazardous conditions that may be found. Inspectors will not enter the home at any time. The testing of backflow devices for irrigation systems and other testable devices will be required as part of this program as well.

HydroCorp will be responsible for conducting inspections and track all device testing for the City. They are currently responsible for the commercial cross connection program and will transition to administrate both programs.

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What is a Cross Connection?

A cross connection can be described as a connection or arrangement of piping through which “backflow” of nonpotable water could flow directly into the public drinking water supply. Backflow is a reversal of flow in a public supply that allows water of questionable quality, containments, and wastes to enter the distribution system. There are two types of backflows, backsiphonage and backpressure. Backsiphonage can occur during water main breaks or during firefighting activities. Back pressure can occur if pump starts and creates a higher pressure area than the downstream pressure. Both types of backflows are real concerns for water operators and can occur in commercial and residential plumbing.

The best way to prevent a cross connection is to separate the potable and nonpotable water supplies completely. If a separation in plumbing cannot be achieved, there are backflow devices that can be installed on plumbing to prevent backflow from occurring. There are a variety of backflow devices available and their application depends on the degree of hazard of the cross connection.

The City participates in a cross connection program as required by EGLE. To achieve compliance, this program mandates regular site inspections to investigate the plumbing of commercial, industrial, and residential properties. It also requires the periodic testing of backflow device. The goal of our cross connection program is to ensure the health and safety of our residents and provide drinking water absent of water quality containments.

Backflow Devices

Hose Bib Backflow Devices
Exterior faucets on homes have a higher probability of a cross connection due to the application of a hose. Hoses are used for a variety of reasons and can be connected to containers used for herbicides, pesticides, detergents, and other hazards. There are a twodevices available for use to protect the health of our community and preventing cross connections from occurring. Both devices consist of a spring loaded check valve that is normally in the closed position, and a vent, that is normally in the open position. When the device is pressurized, the check valve will open and the vent will close, allowing water to flow through the device. Under a backsiphonage condition, the check valve will close and the vent will open, allowing air into the system to prevent backsiphonage. These products can be purchased at your local hardware store. The City of Brighton’s cross connection program requires the installation of backflow devices on exterior faucets.

Atmospheric Anti-Siphon Outdoor Faucet (ASSE #1019)
These are approved backflow devices which are designed and manufactured with an approved internal backflow device that is effective in preventing backsiphonage from occurring. These devices are not testable, but need to be monitored periodically to ensure they are in good working condition.

Hose Bib Vacuum Breakers (ASSE #1011 and #1011 Frost Free)
These are approved devices to prevent a cross connection from occurring at your exterior spigot. Hose Bib Vacuum Breakers (HBVB’s) are small devices that are similar to atmospheric vacuum breakers. HBVB’s are typically attached to hose bibs that are then connected to garden hoses and spray outlets. They are also considered to be non-testable devices.

Pressure Vacuum Breakers (PVB)

Pressure vacuum breakers are among the simplest and least expensive types of mechanical backflow preventers. When properly installed, they provide excellent protection against backsiphonage.

Properly installed pressure vacuum breakers (PVB) will provide excellent protection against backsiphonage for lawn irrigation systems. Pressure vacuum breakers consists of a spring loaded check valve, spring loaded air inlet valve, test cocks and two shutoff valves forming an assembly. Because of the spring loading, it can be installed where it will be under continuous pressure for long periods, i.e. be installed with a downstream shutoff valve. PVBs are testable assemblies and must be tested at regular frequencies. The following are general installation requirements for vacuum breakers:

Must be installed in a vertical position.
Shall be installed “in line” and be the same size of the supply piping.
Must be installed a minimum of 6-inches above all downstream piping and the highest outlet (sprinkler head) or flood level rim.
Shall not be installed in areas where spillage is a concern (unless it is spill resistant type).
Shall not be installed in a vent hood or other areas where toxic or other fumes are present.

Questions? Contact US!
City of Brighton Water Dept.
dps@brightoncity.org