Tuesday, March 26, 2024

When The Bridge Fell In Milton, March 1987

The Milton West Milton Bridge Collapsed on Friday March 27th, 1987, while a new bridge was being constructed beside it.  All of the vehicles on the bridge were able to exit just before it gave way.

See a history of the various bridges between West Milton & Milton here:

The concrete bridge arch bridge in Milton was opened in July of 1925, although the west lane was not completed until later, and the official grand opening ceremony was held in May of 1926

In 1987, a new bridge was being constructed, to replace the 1925 bridge.

On the afternoon of March 27th, motorcyclist Rodney W. Finan rode over the old bridge on his motorcycle, and he knew something was wrong.  When he got to the other side, he stopped traffic, telling motorists it wasn't safe to cross.

At 3pm on  Friday March 27th, the concrete bridge collapsed. 

Although some traffic was moving across the bridge at the time, no vehicles were on the section that fell ingo the river.

Within minutes, a rumbling was heard, and a 125 foot span at the eastern end collapsed into the West Branch of the Susquehanna River.

Penn Dot bridge engineer Jim Seksinsky said that the "66 year old span failed slowly enough that people noticed it and got off." [that dates the span to 1921]

It is thought that  the pylons for the new bridge that was under construction changed the water current,  putting more pressure on the already weakened and failing bridge.

Or more specifically, Penn Dot officials stated that unusually swift water around the causeway, a dirt road into the river, caused erosion under the the bridges pier, causing it to tilt backwards.

A 125 foot section of the bridge fell into the west branch of the Susquehanna River, when a pier supporting it tilted west.

It was reported that the piers for the Milton/West Milton Bridge were likely constructed at different times - earlier piers being made of stone, and later, newer piers made of concrete.

Stephen R. Simco, the states chief bridge inspector, said that the problem may have occurred because the pier that tilted was old and made of stone, and was probably not embedded as deeply into the river as the newer concrete piers.  "The stone pier that tilted was on a higher elevation and more sensitive to scour."

Pier scour occurs due to the acceleration of flow around the pier and the formation of flow vortices (known as the horseshoe vortex). The horseshoe vortex removes material from the base of the pier, creating a scour hole.

When the new bridge opened on November 4th 1987, Finan, the motorcyclist who warned others of the impending collapse, was the first to cross,.  Behind him in the procession was John Yingling, who had been in the line of traffic waiting to cross the bridge when Finan stopped traffic with his warning.

Wooden nickels were passed out to the first 500 motorists to cross the new bridge, which opened about a year ahead of schedule.  

Another Collapse, that Same Day in 1987

Earlier that same day, another bridge had collapsed in Snyder County.  A 30 ton cement mixer truck has attempted to cross a small bridge over Mahantango Creek, Between Snyder and Juniata Counties.  The wooden bridge had a weight limit of 9 tons, and collapsed when the truck got to the middle.

Bridges throughout the area were scrutinized, and in Bloomsburg the East Bloomsburg bridge was closed for a short time while divers inspected the piers to be certain they were sitting on a firm foundation.


More about the Snyder County Bridge Collapse

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