I do not understand the cross connection of the main water service and supply to the kitchen. Take a look at the images, the valve is the main shut off. Why have the “T” fitting to the cold water side of the water heater? Do we need a check valve? Opinions appreciated. 
Looks like the t in the first pic, simply splits the cold supply. One way goes through the foundation (probably to a hose bib or the rest of the house), the other to the water heater.
Am I missing something?
I was looking at the wrong valve, Monday morning brain damage from too many weekend parties and 20" of snow!
It happens, even without snow. 