most likely by what you describe there is a bridge that is low.
not knowing your area but looking at the map, perhaps 35W has a low bridge?
the katrina loads were high priority loads. i had some friends that were on some, there was no hesitation to hand out permits like Halloween candy after it hit. there were also some bridge strikes because of it. but i believe that is what your looking at.
a few tips for your safety:
look both ways before you pull out, it would not be the first time i was driving down the wrong side of the road and had someone pull out in front of me.
if your cable or telephone wires cross the road have the cable and phone company's install them higher if they droop. i have pulled down tele and tv wires, and do about 1 per week. here in the north east we are not liable if the wire is below 15'8".
TEXAS. i have been there ONE time. loads have to be huge to have escorts, and the fine to get cough running without one is $250 in texas, that's way cheaper then if they hire one. just be careful.
here is a kinda out dated but good site for photos.
http://www.jsupor.com/HeavyHauling/index1.htm
they carry the HUGE stuff. only up to 500tons thou.