Winter travelers on Route 30 in southeast Hamilton County, N.Y., may not have known it, but at times they were literally riding on solid ice. And that rare but significant occurrence was a key reason behind the replacement of the bridge over the West Stoney Creek in Benson, N.Y.
"There were a lot of ice jams [at the bridge site]," says Engineer-in-Charge Anthony Bruno, with the New York State Department of Transportation's Region 2 office in Utica. "And I believe there were times when the ice actually touched the bottom of the bridge."
To eliminate the ice jamming problem, NYSDOT designed a replacement for the 60-year-old bridge. To rebuild the bridge, DOT selected two precast concrete spans. Formerly a three-span bridge, the pair of piers in the river were removed and replaced with a single pier. The riverbed under the remove piers was restored to its original elevation. Overall the new spans reached roughly 200 feet in total.
DOT also decided to improve the underside of the bridge to further prevent any ice jamming problems. Instead of precast I-beams, engineers selected concrete box beams.
"The new beams were smooth on the underside," says Tim Luster, a DOT design engineer with Region 2. New abutments were built as well. And designers raised the elevation of the new abutments and regraded the approach roadways. Both improvements netted an overall 2-foot increase in the elevation of the underside of the bridge deck.
The project went very smoothly, adds Bruno, except for a few days when the 2006 rains dumped such a volume of water that the dewatering system for the pier cofferdam was overwhelmed and the project had to be placed on hold. "There was a lot of flooding because of the excessive rain," he says.
The deck was created with precast, reinforced concrete box beams supplied by L.C. Whitford of Wellsville, N.Y. Clemente Latham of Gloversville supplied the ready mix.
Tioga Construction Company of Herkimer, N.Y., was awarded the project for just over $2 million on January 12, 2006. Due to Walleye spawning-related restrictions in the stream by the state's Department of Environmental Conservation, workers couldn't enter the water earlier than May 15. The project was completed October 31.
The project is in DOT's Mohawk Valley Region, which includes over 6,000 square miles and nearly 500 bridges.