In an effort to spread out the costs of the system installation I had mine installed in the fall of last year. This part of the project must be installed by a licensed plumber. Its purpose is primarily to prevent the backflow of stagnant or potentially contaminated water from your irrigation system into your household. The cost was roughly $350.00.
I have a basement so this shut off valve and drain is installed inside in the basement allowing it to gravity drain. In the fall the valve is turned to the off position as shown and the spigot is opened to allow water to drain out of the outside portion. This prevents freezing and damage to the back flow in winter.
The next step in this process will be the installation of the system in the yard. I am just about giddy with excitement!