My dishes look through the utility service lines and I have never noticed an issue. High power transmission lines generate a magnetic field around them and have a broader influence on transmissions.
That's a lot of wires... I suspect there will likely be some attenuation. You'll have to try it out and see if signals are ok or not, it's one of those situations that are dificult to predict and subjective; which wires carry electrical power, voltages/load, cableTV signal (good or leaky cable), etc. Certainly better if you can find a spot where you can avoid the wires.