Noozer,

When I lived in Pennsylvania, we needed to bury water lines at least 5
feet deep to prevent freezing in normal winters. A couple of years it
got down to -20, and five feet deep was not deep enough. I would
suggest 7-feet deep for the water line, but ask your local water
company.

The electrical will need (2) #10 hots, (1) # 10 neutral and 1 # 10
ground if you are going to a subpanel in the garage. If you are
putting GFCIs in the house, they cannot share a neutral, so you will
need 2 neutrals then.

I do not know how far apart to separate the gas and electric, but I
would not bury them together without permission from the gas company.
Keep the phone lines and cat-5 away from the power, use separate
conduits.

Stretch