Final answer:
To prevent backflow between the potable water supply and the irrigation system, a means of protection must be installed. This can be achieved by using various types of backflow preventers. The minimum height requirement for installation is typically around 12 inches above the highest head.
Step-by-step explanation:
Backflow is the reverse flow of non-potable water or other substances into the potable water supply system. To prevent backflow between the potable water supply and the irrigation system, a means of protection must be installed.
This can be achieved by using atmospheric-type vacuum breakers, pressure-type vacuum breakers, or reduced pressure principle backflow preventers.
Regardless of the specific type of protection chosen, it must be installed a minimum of a certain height above the highest head of the irrigation system.
The exact minimum height requirement may vary depending on local building codes and regulations, but it is typically around 12 inches.
For example, an atmospheric-type vacuum breaker may need to be installed a minimum of 12 inches above the highest sprinkler head. This ensures that any potential backflow from the sprinkler system does not reach the potable water supply.