I encountered a website covering the 2001 rehabilitation of this bridge from an engineering perspective. I found it a rather fasinating insite to the details of a wooden truss bridge. It inspired me to dig a bit deeper into it's history, in particular the changes to the structure over time.
In the 1940s, after being in service for more than 80 years, the Long trusses were sagging enough a center bent was added. This would explain the listing of 60ft for the longest span here on Bridgehunter.com. The rehabilitation eliminated the need for this bent, so it was removed so the bridge is again a single span.
The bridge was worked on again in 1966. This time, two external butresses were added to each side to correct lean and windows were added so people would no longer knock out siding boards so they could fish from the bridge. The 2001 rehabilitation removed the external buttresses but kept the windows.
The original bottom chord was multiple pieces connected with a bolt-of-lighting splice. The replacement bottom chord is a single piece glue-laminated beam.
Some of the vertical post showed evidence of over-stress. These were replaced with heavier timbers. Some of the existing timbers were move to allow reusing them.
An aspect of Colonel Long's patent is provision of wedges at the connection between vertical post and chord. Originally, there were wedges only at the bottom chord. After stress analysis, it was decided to add wedges to the top chord as well.
The pitch of the roof was increased to allow a more substantial internal bracing while maintaining traffic overhead clearance.
This single span, Long truss bridge is also known as the Hamden Covered Bridge. It was built in 1859 by Robert Murray and measures 128 feet. It was listed on the State and National Register of Historic Places on April 29, 1999. The World Guide to Covered Bridges has assigned the following number to this bridge: NY 32-13-03. Photos submitted by Bob and Trish Kane, Sherburne, NY.