INFORMATION ABOUT NEW YORK COVERED BRIDGES:
New York State, at one time was home to over 300 covered bridges. Many which crossed major rivers like the Mohawk, Delaware, and the Hudson. Many more crossed streams, creeks, and brooks like the Battenkill, Beechers Creek, the Shadow Brook and countless others. Covered bridges once dotted the vast landscape of New York from as far south as Ossining, to as far north as Massena, and from the eastern edge of the state at Granville to the western edge near Buffalo, and everywhere in-between.
Why were the bridges of early American life made of wood? The abundance of wood, the speed at which a wooden bridge could be constructed and the availability of a local labor force to construct them, made wooden bridge building the preferred choice of bridge building in America from the Colonial era until the 1860’s. Since most of the rural road building during the mid 19th century was the responsibility of town governments, they in turn relied heavily on the local expertise and resources. Most early wood truss bridges were simple Kingpost or Queenpost trusses, which were easy to fabricate and erect, and could be used for crossings up to around 50 feet in length. For wider crossings, these trusses were constructed in a series, supported by masonry piers or cribbing between the spans. Some were covered by boards (weather boards) to protect the trusses from the deteriorating effects of the weather.
Throughout the years, many people have asked, “Why were the bridges covered?” There were many ‘so called’ reasons for doing this, such as to make it look like a barn, therefore the animals would enter easier than if they saw the raging rivers below. Other theories were that it would help form a load of hey when it was pulled through the portal, and yet another was to keep the snow off the roadways. The last theory proved incorrect, as during the winter months, many people used sleighs for travel and there were actual bills to show that people were paid to ‘snow the bridge’. Snowing the bridge meant that snow would actually have to be shoveled into the bridge and it would cover the floor boards, allowing the horse drawn sleighs to cross the bridge easier.
These all sound like good reasons, but the real reason for covering a wooden truss bridge was to protect the interior supporting timbers from moisture. Seasoned wooden beams that result from years of exposure to air, but not moisture actually gain in strength. The roof, side boards, and even the floor boards were replaceable, but it was vital to protect the trusses, or “bones” of the bridge from dampness. Moisture would cause the wood to become soft and rot, thereby cutting short the life of the bridge. Covering the wooden truss was a very frugal idea, especially when you took into account that a wooden truss bridge that was left uncovered would need to be replaced in ten to twenty years, thereby causing another bridge to be built at more than the cost of the original bridge. Almost all of the authentic wooden truss covered bridges still standing in New York State are over one hundred years old. The Empire States oldest covered bridge is the Hyde Hall covered bridge in Glimmerglass State Park at the north end of Otsego Lake. The date of construction is circa: 1825.
In the early eighteen hundreds, Major Salmon Wheat was credited with building the first covered bridge in New York State. It was a rugged arched span which crossed the Neversink river at Bridgeville in Sullivan County. Completed in 1807, it was in continuous use for over one hundred years before it was eventually removed in 1917.
In 1804, a sawmill owner named Theodore Burr invented a truss that is know as a Burr Truss. Patented that same year, the truss consists of a simple parallel chord truss and wooden arch. At Waterford, N.Y., Theodore Burr’s four span eight hundred foot wooden arch bridge was the first to be erected across the Hudson river. Because of his arch design, craftsmen were now able to build bridges of great lengths without the use of piers. His design became a major advancement in bridge building and a prototype for hundreds of future covered bridges. The best example of Burr’s arched truss in New York was in the massive oak arches of the Blenheim bridge that crossed the Schoharie Creek until it was lost in the flood waters of Hurricane Irene in 2011. It was the longest single spanned wooden covered bridge in the world at 228 feet in length.
The next major improvement in wooden truss design was invented by Ithiel Town and was patented in 1820. His Town Lattice truss was a latticed web parallel chord truss, given it’s rigidity by the top and bottom chords, and were connected with the use of hand turned wooden pegs called tree nails, but more commonly called ‘trunnels’. This truss design was a real innovation, as local carpenters and craftsmen could easily assemble one of Town’s lattice truss bridges. It was said that a Town lattice truss could be built by the mile, and cut off by the yard.
In 1830, Colonel Steven H. Long of the United States Army Topographical Engineers established himself as another wooden truss patentee, when he invented the Long truss design. It was the first wooden truss in America where a few mathematical calculations were entered. His truss design was a panel truss which needed no arches. When viewed from the side, the Long truss resembled a series of Boxed X’s. This truss design vied with Town’s lattice design truss for favor among the lands railroad networks, toll bridge companies, and town highway planners for about ten years. After 1840 though, both Town’s and Long’s patented wooden truss bridges were almost totally eclipsed by the introduction of a new truss design.
The next wooden truss design was a revolutionary improvement invented by William Howe in 1840. Howe’s truss design resembled Long’s truss design so much that Colonel Long claimed patent infringement for years. He never got any satisfaction from the patent office, for the ‘improvement’ Howe claimed was a real step forward in truss design. in Howe’s design, the upright wooden beams were replaced with iron rods in tension, and also lightened the weight of the truss significantly. These timber and iron trusses were widely used in the construction of railroad bridges, and could be constructed miles away, and loaded onto flat cars, and transported to the building sight. It was an early example of pre-fabrication at it’s best. In the United States, more Howe truss spans were built than any other wooden truss type.
Today in New York State, all of these wooden truss designs are represented. Although a few additional replicas have been erected in recent years, only twenty-three Empire state covered bridges are considered Historic Authentic examples. Theodore Burr’s arch truss design is represented in the Hyde Hall, Salisbury Center and Perrines bridges. William Howe’s truss design is evident in the Jay, Buskirks and Rexleigh bridges. Colonel Steven Long’s truss design is used in the construction of the Downsville and Hamden bridges. Itiel Town’s lattice truss design bridges are the most prevalent in New York today. This truss design is used in the Beaverkill, Bendo, Lower Shavertown, Eagleville, Fitches, Grants Mills, Halls Mill, Newfield, Shushan, Van Tran Flat, and Olive/Turnwood bridges. The Copeland bridge uses a Queenpost truss design, and the Tappen and Forge bridges incorporate the Kingpost truss design. The shortest Historic covered bridge in the state is the Forge covered bridge at 27 feet long. Since the Blenheim bridge was lost in 2011, the longest covered bridge in the state is now the Jay bridge at 175 feet in length.
Wooden truss bridges at one time were numerous throughout the Empire State. Today, only 22 of these survivors of an era long since gone are still present. Fifteen of these covered wooden spans continue to serve in the capacity for which they were intended. The rest are either by-passed and preserved to some degree, or stand on private property. These testimonials of fine woodworking craftsmanship are a rare sight indeed. They should be preserved for future generations to appreciate.