Flatiron Construction Corp.

Flatiron is constructing the new Lake Champlain Bridge in northern New York State. The new two-lane steel arch-span structure replaces the structurally deficient two-lane bridge that was demolished in December 2009. Spanning Lake Champlain, the 2,200-foot-long bridge will reconnect Essex County, N.Y. and Addison County, Vt.

Currently, those travelling between the two counties rely either on a 100-mile detour around the lake or a ferry system initiated after the existing structure was closed. Once construction is complete, the motorists will enjoy a delay-free crossing. The impact to the local community is the driving factor for the aggressive 490-day completion schedule.

The bridge includes construction of 1,029-foot approach on the New York side and a 769-foot approach on the Vermont side. The main span is comprised of a basket handle modified network steel tied-arch that will be 402-feet-long and 80-feet-tall, supported on delta fixed frames. It has a basket handle arch with a network cable arrangement and internally redundant box tie girders supporting a composite precast deck system. The entire main span structure will be built on land at an off-site location and floated to the site on barges where strand jacks will be used at each corner to complete erection. A main feature of the new bridge is the zinc metalized corrosion protection that will be applied to the structural steel. The new bridge one of the largest in North America to be completely zinc metalized. This treatment bonds the zinc to the steel, an improvement over traditional steel weathering and painting, extending the time before maintenance is required. The work also includes roadway approaches on either side of the bridge and demolition of temporary causeways and ferry docks.

Renderings courtesy of bridge designer HNTB.