If you cannot find it, make a call to your delivering dealer. If no luck, call around to CW stores and inquire regarding your model. OR, you can trace it by following every line to the HW heater. It's not hard to find, but can be a PITA since there is no consistency.
Just for example; on my Outback, I have to crawl a small way into the compartment where I generally store my outside stuff; pull out 2 screws and remove a panel, search like a mouse needing cheese on the rear of the HW holding tank and there , by golly, is a small lever that when pulled down closes the water intake to the tank.
As I said, each is different, but persistence will pay off,
Good luck....