As you know, the official clearance on those fixed bridges is 65 feet, so you are very close. Obviously, you can clear at least some of those bridges as you got there somehow, unless the mast
was down. I don't think any of the bridges in that stretch are known to be particularly low, but you will have to proceed with great caution. Fill up with water
before you leave (to sink the boat). Also, have you measured your clearance? Often builders or designers notes are inaccurate with regard to actual clearance.