Running water to my garage

[sheslostcontrol]

I'm going to be digging a trench for low-voltage cabling (coax, security, ethernet) soon. While I have a trencher I am thinking about some other improvements....

My long range plan is to install a bathroom in the garage, but it is currently not stubbed for any plumbing. This leads me to a couple questions....

1) Should I go ahead and run another trench for some pex, and lay that down to the garage?

2) If so, what is considered "Code" for running a water line to an outbuilding? How do I properly tie into my existing water system? Do I have to connect a Y fitting at the street, or can I commandeer an unused water spigot under my deck?

[sberry]

As far as I know you can source water anywhere you can get it, needs to have sufficient pipe size, usually 3/4 for small garage and buried deep enough frost isn't an issue where you live.