Hadley Parabolic Bridge

The bridge is located just above where the Sacandaga flows into the Hudson River opposite the village of Lake Luzerne, and just south of the central portions of Hadley.

The river flows rapidly through a deep gorge here, with its sides sloping steeply from the road grade.

The 45-foot (14 m) span at the south end is an end-post three-panel pony truss with both cast and wrought iron elements.

All joints, not just in this span but the main one as well, are secured by threaded iron pins two inches (5 cm) wide capped with hexagonal nuts.

A set of expansion rollers at the west end, intended to provide additional stability, has since corroded due to road salt and rust.

[2] The lenticular truss bridge design was developed by engineer William O. Douglas of Binghamton, who patented it in 1878.

[citation needed] Many of the lenticular trusses were found to be insufficiently stiff despite the lateral bracing, and the design's popularity waned in the early 20th century.

In 1926, the construction of the Lake Luzerne bridge on what is today NY 9N created a newer option for long-distance travel through the region, and ownership reverted to the town.

The deck support system was changed from timber to iron, and the roadway itself was narrowed by 18 inches (46 cm) with a wooden curb so that it would only have enough room for one vehicle at a time, with a speed limit of 10 miles per hour (16 km/h), thereby further reducing loads.

The county was planning to dismantle the remaining structural components, but delayed that at the request of some local historic preservation groups.

This unprecedented act of personal dedication highlights the cultural and emotional significance of the bridge, reflecting its iconic status in the community and the deep connection felt by those who work and live in the surrounding area.

The road deck of the bridge.