Protecting Your Drinking Water

The Town of Johnstown is focusing on backflow prevention - the reverse flow of contaminated water into a building's water supply. The law requires that every connection with the public water system be protected with a backflow prevention device. These devices must be tested by a licensed Backflow Tester during initial installation and then annually. A test report must be filed with Aqua Backflow.

Pertaining to backflow devices, the Town has hired Aqua Backflow to manage and monitor backflow assemblies, track existing devices, identify the need for businesses to install a new device, ensure that devices are tested annually, and improve communication with water customers. This is a major step forward in the protection of the Town's drinking water to prevent contamination by end users. 

Currently backflow requirements apply to commercial businesses and multifamily units. It is the responsibility of the property owner to have backflow prevention assemblies installed and tested by a Certified Colorado Cross Connection Control Technician who is also licensed with the Town of Johnstown.

If you have a backflow prevention assembly on your property, please do your part to ensure a safe drinking water supply for yourself and everyone in Johnstown. If you have any questions about Johnstown's Cross Connection Program, please feel free to call the Public Works Department at: 970-587-4664. You can also send an email to or

What are Backflow Preventers?

In an unprotected system, water can flow both in and out of a building or fixture. When water service is interrupted in the street or in a building for any reason, there is a pressure drop which can draw contaminated water backwards into the water system. Backflow preventers, also known as Reduce Pressure (RP), Double Check (DC), or Pressure Vacuum Breaker (PVB) devices, protect the Town's water supply from outside contamination. The devices operate by allowing water to flow in only one direction.

Backflow protection is required wherever an end user poses a risk of polluting the Town's water. 

Backflow prevention assemblies MUST be installed on all commercial, industrial and multi-family, service connections to protect the Town's water from cross connection with the customer. 

Internal protection is also HIGHLY RECOMMENDED, by installing backflow devices on internal machinery that is directly connected to a water supply to protect industrial and commercial customers from potentially hazardous cross connections in their own system.

The Town of Johnstown Public Works Department takes all precautions to protect the water entering your system. We take pride in the high quality of the water we provide and we will continue to protect it for our residents.  However, once the water enters your business property you become responsible for protecting the water quality. As a consumer, you must be aware of cross connections and prevent them. By testing the backflow prevention assemblies annually, and performing repairs when needed, you are helping us to ensure that the assemblies are operating properly. With cooperation, a comprehensive Cross Connection Control program together we will keep a purified water distribution system free from impurities and health hazards. 

Omission to Regulations

Due to the potential threat to public health and safety, violations involving Cross Connection may be subject to citation, fine and water service disconnection. 

The contractor hired by the Town of Johnstown to implement and oversee this program is Aqua Backflow. Aqua Backflow can be reached toll-free at 866-777-2124 with any questions. You may also contact the Town of Johnstown Public Works Department at 970-587-4664 with any questions.

The Town of Johnstown Cross Connection Control Program is designed to safeguard public health. We ask for your cooperation with our program, its enforcement, and any request for information that comes from either Aqua Backflow or Town Staff.

To learn more about Backflow Prevention go to