Warning System For Overly Tall Trucks –

In Search Of A Better Mousetrap For Would-Be Bridge Victims

By Andrew Gorosko

The Police Commission is asking the state to install electronic sensors at the Church Hill Road railroad overpass to warn truckers when their vehicles are too tall to pass under the bridge without striking it.

Police Commission members July 5 agreed to ask the state Department of Transportation (DOT) to install the warning system, known as an Overheight Vehicle Detection System (OVDS), at the black steel span which has been struck by trucks for decades. The commission serves as the town’s traffic authority.

Although the posting of low-clearance signs and flashing warning lights on the overpass several years ago appears to have reduced the number of accidents there, the span is still often struck by errant truckers with vehicles too tall to pass under it. The overpass has a 12-foot, 7-inch clearance. The modern standard for bridge clearances in 13 feet, 6 inches. The overpass, which is owned by the Housatonic Railroad, is used to haul rail freight between Botsford and Hawleyville.

Of the OVDS proposal, Police Commission member Carol Mattegat said, “This is a great idea. I think this is a wonderful idea. This is fabulous.”

Commission member Charles Pilchard suggested that the state simply hang some chains from the overpass which would alert truckers of a clearance problem when their vehicles hit the hanging chains.

Acting Police Chief Michael Kehoe said that to be effective, any OVDS system would have to be installed for vehicles approaching the overpass from both directions.

Police Commission Chairman James Reilly said the state would assume the costs for warning system installation. The warning equipment could be dismantled and used elsewhere in the state after a planned new, higher overpass is constructed to replace the existing overpass, he said.

New Bridge

Installing a warning system would be a temporary measure intended to prevent bridge collisions until the new bridge is in place.

The state plans to replace the Church Hill Road overpass with a new, higher span which meets modern clearance standards, but that replacement won’t be made until the end of 2001, at the earliest, according to the Housatonic Valley Council of Elected Officials (HVCEO), the regional traffic planning agency.

Building a new, higher railroad bridge is more complex than it would appear, because the elevation of the railroad tracks approaching a new bridge from both directions must be increased for considerable distances in order to increase the bridge’s height. 

The overall volume of truck traffic under the low-clearance overpass has decreased during the past several years with the opening of the Fairfield Hills bypass road, a thoroughfare which provides truckers with an alternate east-west route through town. Later this year, the DOT plans to install signs on Interstate-84 alerting truckers that the preferred east-west truck route through Newtown is the Fairfield Hills bypass road, not Church Hill Road.

In response to a request from First Selectman Herbert Rosenthal for aid in preventing trucks from colliding with the railroad overpass, HVCEO Deputy Director David Hannon wrote to Mr Rosenthal that three OVDS systems are in use in the state to prevent trucks from hitting low overpasses.

Such systems use beams of light, which when interrupted by an overheight vehicle, switch on an electronic sign which warns the truck driver that his vehicle is too tall to pass under the span. The system directs the driver to turn off the road and alerts the police department of the situation. The system also has the ability to activate warning bells, a stop light, very bright flashing lights on the overpass, or to drop a crossing gate to block the road in front of the overpass.

The three low-clearance warning systems in use in the state protect railroad overpasses. They are located on Route 67 in Seymour, Route 110 in Stratford, and Route 106 in New Canaan. Bethel also has requested that the DOT install a warning system for the Route 53 railroad overpass there.

The Seymour warning system has been in use for eight years and appears to be successful, according to a DOT study. DOT installed the New Canaan system last April.

“The Seymour [warning system] was constructed for a total cost of $63,200. If such a system could be installed on Church Hill Road at a cost of, say, $100,000, that would represent about 2 percent of the total project cost to replace the railroad bridge,” Mr Hannon wrote.