Backflow Prevention

What is backflow?

Backflow is a loss of pressure in the public water system that can draw water on customer property (from within fire sprinkler systems, irrigation systems, hot tubs, etc.) back into the public water system. This water can contain contaminants that would put the public water supply at risk. Studies have shown links between waterborne disease outbreaks and the backflow of contaminants from private property. It is critically important to prevent backflow to protect public health.


What am I responsible for?

Commercial properties and properties/usage categorized as “high risk” are required to install and maintain backflow prevention assemblies where they are needed. Water utility customers are also responsible for any costs related to maintaining and testing their backflow assemblies. The District uses a third party contractor for annual testing and handles necessary scheduling to help keep costs down and ensure that all testing is done consistently and adheres to regulatory requirements.

Where is a backflow assembly required?

A backflow assembly is required wherever there is a risk of contamination of the public water system. Examples include, but are not limited to, irrigation systems, drainage systems, hot tubs, and other water-using equipment. The Colorado Department of Public Health and Environment regulates drinking water quality and standards. The Colorado Primary Drinking Water Regulations (Regulation 11) outline the District’s requirements for cross-connection control and backflow prevention.

A warning about outdoor faucets

Everyday things you do when using an outdoor faucet can put you and your family at risk. If an outdoor faucet is in contact (directly or via a hose) with dirty water and there is an unexpected change in pressure, that water can be sucked back into your home’s drinking water pipes.

Tips to prevent outdoor faucet backflow

The easiest and best way to protect your family is to install vacuum breakers on all outdoor faucets. Vacuum breakers completely prevent backflow through outdoor faucets and are available at all major home improvement stores for around ten dollars.

If you choose not to install vacuum breakers make sure you:

Never submerge a hose in a bucket of water

Hold hoses above the water line when filling hot tubs, pools, etc.

Do not use fertilizer sprayers

For More Information

For more information and full program details, see our Backflow Prevention & Cross-Connection Control Program Guide.

Left Hand Water District