How deep will ComEd bury their plant? You can follow in "their" trench but, keep at least a foot of dirt between them and your telephone/CATV. This also applies to placing your cables in plastic pipe. Depending on bends and turns you should be able to get by with 3/4" pipe.
But, why bother? Both Telco and CATV will deliver to your house. Let them take on the expense. Just make sure you run your "outside" cables from inside your house to an area that accessable to them - usually near the electric entrance.
