I feel ok but some of those power lines in town makes you second guess about going through.
If the "overhead" is not marked it "should" be 14'+
Power lines over the roadway "should" be 18' NEC (
http://www.naffainc.com/x/cb2/elect/overheadserviceconductors.htm)
Cable and phone will be lower, but still should be at least 14'
100 degree plus days, you better be careful with the wires, they can sag below the minimum, especially older stuff where poles and supports could have moved.
And if you snag a power line on a roadway, don't let anyone BS you about having to pay for it - it shouldn't be that low.
I have found now with about 20K miles of towing, most unmarked structures are high enough.
Most marked structures are correctly marked.
Most structures that look too low, no matter how they are marked, probably are. Especially older train bridges that have had multiple re-pavings before the milling become popular.
And some are just wrong. We have a train trestle in our town that is marked 10'2". Our ladder truck is 11'5". We have used that road for 30 years - until. One day while returning from an alarm we hit the bridge. Mind you, we went through the same bridge 20 minutes prior.
What had happened was the bridge had been hit by a truck and the "web" was bent down a bit. We actually managed to hit that bent portion, that had a rivet sticking even lower (was an old bridge). The rivet hit the 1" wide portion of the ladder beam. Just a minor dent in the ladder.
Turns out the bridge had always been marked wrong and never corrected with years of re-paving, because at 10'2" it should have kept the trucks at bay.
It is still marked incorrectly, but is now off limits to ariel apparatus.
And you can't fix stupid
http://11foot8.com/
If you look close at some of the shots you can see where a steel I-beam has now been built in front of the bridge to protect the bridge itself.