Cross Connection Control Program

Updated on October 30, 2025

Cross Connection Control

The RDN owns and operates nine public water systems and three parks with drinking water facilities in Central Vancouver Island. These water systems operate under the terms of Operating Permits issued by the Island Health Authority. A condition of these Operating Permits is that there is a Cross Connection Control Program in place. This program helps protect public health by reducing the risk of contaminants flowing back into the public water supply. 

The RDN's Cross Connection Control Program addresses cross connection threats by establishing operating policies and procedures. It also establishes selection, installation, testing, and maintenance practices and procedures for backflow preventers. This program operates in line with RDN Cross Connection Control Regulation Bylaw No. 1788, and the British Columbia Building Code. 

Cross Connection Control Program

What is a Cross Connection?

A cross connection is a link or structural arrangement where drinking water in a distribution system can be exposed to unwanted contaminants. It is a point which it is possible for a non-potable substance to come in contact with the drinking water system.

What is Backflow?

Backflow is the reversal of the normal flow of non-potable water through an unprotected cross connection into the public drinking water system.

Cross Connection Control

The best way to prevent hazardous backflow is to eliminate all existing cross connections in your home and yard. If a cross connection cannot be feasibly eliminated, it must be protected by an approved backflow prevention device selected and installed in conformance with the Canadian Standards Association CSA B64.10 standard.

Every RDN water service line is required to have a non-testable dual check valve (backflow preventer) in-place at all times. If a higher risk of cross connection exists, a testable backflow preventer device will need to be installed.

Additional Resources