What is a cross connection? Why is it important?
A cross connection occurs whenever there is potential for liquid to come in contact with existing GID waterlines. e.g if you have a hose going into any container, and the hose end is submerged (filling a pool or hot tub; filling a stock water tank or pond; filling a bucket of water; connecting well water to GID pipes; using a hose siphon for applying chemicals or fertilizer)
It is important because any drop in GID water pressure can result in contaminated water being siphoned back into the main line and causing contamination of the system. Nick and Mabel Denisoff recalled an incident where that occurred in Glade. The main water had been shut off for some reason. An upstream neighbor had been filling their swimming pool when that happened. Nick and Mabel continued to have water in their taps even though the main water was off. The water that was coming out of their taps was from the neighbor's swimming pool!
Glade water pressure can drop at anytime there is an increase in water usage. It is particularly important to be aware of pressure drop when the system is shut off for maintenance.
Our current bylaws require an actual Air Gap for any potential cross connection. This means that there should NEVER be a hose submerged in another body of water. see here for more info
Diagram of Air Gap installation
An excellent reference for more complex solutions to prevent cross contamination for continuous refilling of pools and stock tanks is found here.
Methods other than an air gap will require inspection by Water Systems Operator.
A cross connection occurs whenever there is potential for liquid to come in contact with existing GID waterlines. e.g if you have a hose going into any container, and the hose end is submerged (filling a pool or hot tub; filling a stock water tank or pond; filling a bucket of water; connecting well water to GID pipes; using a hose siphon for applying chemicals or fertilizer)
It is important because any drop in GID water pressure can result in contaminated water being siphoned back into the main line and causing contamination of the system. Nick and Mabel Denisoff recalled an incident where that occurred in Glade. The main water had been shut off for some reason. An upstream neighbor had been filling their swimming pool when that happened. Nick and Mabel continued to have water in their taps even though the main water was off. The water that was coming out of their taps was from the neighbor's swimming pool!
Glade water pressure can drop at anytime there is an increase in water usage. It is particularly important to be aware of pressure drop when the system is shut off for maintenance.
Our current bylaws require an actual Air Gap for any potential cross connection. This means that there should NEVER be a hose submerged in another body of water. see here for more info
Diagram of Air Gap installation
An excellent reference for more complex solutions to prevent cross contamination for continuous refilling of pools and stock tanks is found here.
Methods other than an air gap will require inspection by Water Systems Operator.