Low Overhead

by Virgil Soule. 0 Comments

  About a month ago, the News-Post reported on a stuck-truck incident at the rail overpass on MD75 in Monrovia. I was curious, so I drove over to see what might be causing problems for the truckers. The truckers are being blamed and Maryland SHA considers the matter closed, but It appears to me that the SHA might share some of the responsibility for the low-overhead problem.

  On the interstates, the roadway is straight and flat going under overpasses. A long truck will have the same clearance front and rear as it passes under. Truckers know their clearances and rarely have overhead problems.

  The overpass in Monrovia is different. The roadway undulates up and down as you pass under the overpass. In the most-recent incident pictured in the June 22 News-Post, the truck was coming from the South. It apparently had clearance going in, but then the roadway rose up in front, which forced the front end of the truck up and trapped the trailer in the middle. If the roadway had been flat for a truck-length on either side of the overpass, the trucker would have gotten through with clearance to spare.   The clearance is posted as 12 ft., 6 in. for the overpass. Given the irregularities in the roadway surface, it is probably somewhat less than that for long trucks. Short trucks might get through at that height but not eighteen-wheelers. Measuring the actual clearance height for long trucks – front, middle, and rear – ought to be a simple surveying task.   Truckers are apparently using MD75 and MD80 as a shortcut between I-270 at Urbana and I-70 at Monrovia. This makes MD75 a legitimate commercial route and places some obligation on Maryland SHA to make it accessible to all truckers. All they would have to do is to re-grade the roadway on either side of the overpass to give long trucks the same clearance front and rear as they go under the overpass.   A minor matter, perhaps, but in this "green" era, any shortcut that reduces a trucker’s fuel burn is a step toward energy independence.

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