I am running underground electrical to a detached garage and want to run cable/phone, gas, and water along with it. I already have the electrical ran in 2 inch conduit done and want to add the water, gas, and cable/phone. The trench now is 2 feet deep and 2 feet wide. What are the space requirements between all four? Do they go side by side or on top of one another? Also what kind of material should I use for the water and natural gas? I am in southern california so freezing is not an issue. Any help would be greatly appreciated. Thanks.