Shoreham Covered Railroad Bridge, Shoreham Vermont
Some of the earliest railroad bridges were timber structures because wood was abundant, cheap, and easy to work with. In 1830, Lewis Wernwag built the first wood railroad bridge in the United States for the Baltimore & Ohio Railroad over the Monocacy River in Maryland. Within a short time, wood bridges were commonplace on America's growing network of railroads.
Presumably hundreds of covered railroad bridges were built in the nineteenth century. In 1841, one English traveler noted, "The timber bridges of America are justly celebrated for their magnitude and strength. By their means the railways of America have spread widely and extended rapidly." By the late nineteenth century, most railroad bridges were being built of iron or steel. In 1957, there were only 29 surviving timber truss railroad bridges in the country. Today there are eight. The Shoreham Railroad Bridge is one of only two wooden covered railroad bridges left in Vermont.
In 1870 the Addison County Railroad was chartered to build a line connecting the Rutland Railroad at Leicester Junction, Vermont, with the Delaware & Hudson Railroad at Ticonderoga, New York, a distance of 15.6 miles. The line was laid out from Leicester Junction westward through the towns of Whiting, Shoreham and Orwell across Lake Champlain in New York. The contract for building the road, including a floating bridge across Lake Champlain, was let to W. Phelps & Son, at a cost of about $500,000.
In the southeast corner of Shoreham, the line crossed the county's "only stream of consequence," the Lemon Fair River, at a hamlet known as Richville (formerly Rich's Mills). A bridge was built here in the fall of 1871, according to the following report from The Middlebury Register. "ARR is in running condition from Leister to the Lemon Fair. It will be two weeks before the bridge over the stream will be ready for trains." Another item that appeared in the same paper October 3, 1871 suggests that most of the bridges on the line were Howe trusses:
The 1897 Biennial Report of the Rutland Railroad Company indicates that there were four wooden trestles and seventeen wooden bridges (12-108' span) on the Addison Railroad line. Further information on these other bridges has not been found, but they were presumably minor structures, since the Lemon Fair is the only major watercourse along the railroad right of way. The line was completed in December 1871, and the newspaper reported: "An excursion train passed over the road on Wednesday and greatly rejoiced the hearts of the people living along the line of the road."
The date of construction of the present covered bridge at East Shoreham is not conclusively documented in records found to date. While the railroad was clearly building timber Howe truss bridges on the line in 1871, most modern sources state that this bridge was built in 1897. More recently, the Shoreham Historical Society states that 1891 "may be the true date," although the author has not seen any supporting documentation for this date. The iron rods in particular are a subject for further investigation—their arrangement and connections have an odd appearance, as if some of them were added later.
What is well-documented is the fact that although it first held promise as a freight line, the Addison Railroad primarily served local farmers, carrying dairy products, wool, hay and livestock to market, and the line never turned much of a profit. After the Vermont Central leased the line in 1872 they did not maintain it. Trains were rerouted across the lake at Rouses Point and "very little was sent by way of the Addison Railroad." Within just five years, the line was so badly neglected that trains were limited to speeds of 15 miles per hour. On December 13, 1879 an engine nearing Larabees Point tipped over and rolled down the embankment, killing three people. Although that event was "hushed up" according to historian Harold Webster, local people were determined to bring the railroad's dangerous condition to someone's attention. H.S. Brookins, one of Shoreham's influential citizens, eventually filed a complaint with the Vermont Railroad Commission and a number of subsequent inspections took place. An inspection in 1889 reported that the Addison Railroad was one of the most neglected lines in the state.
According to Webster, sometime shortly after that, improvements were made, because "By 1891, the Addison Railroad had been improved so much with more ballast and repaired bridges that they raised the speed limit to 20 miles per hour." The Vermont Railroad Commissioners Reports, published from 1888, discuss repairs to the line in the 1890s. Regarding the bridges, the commissioners stated in 1894: "The bridges are few and short, but are believed to be equal to the strain which the light traffic of the road exacts." The 1898 report indicates that one new wooden bridge was built on the Addison line during the year ending June 30, 1897, but does not record the location of that bridge. The only written reference to this specific structure in railroad records discovered to date appears in a 1917 valuation of the Addison Branch line, which shows a "covered timber bridge, stone abutments, #A15 at this location." While no conclusive documentation has been found to substantiate a construction date, the bridge's heavy construction and unique arrangement of tension rods suggests that the bridge was at least strengthened, if not constructed, in 1891 or 1897.
The Shoreham Railroad Bridge carried trains until 1951, when the Rutland Railroad decided to abandon the line, stating their reasons as "There is little demand for carload freight and the traffic available is not sufficient to warrant necessary outlay for reconstruction and maintenance." The petition was granted and the tracks were pulled up as far as Whiting in 1951 and the remaining tracks pulled up ten years later. Subsequently, the bridge and surrounding property were purchased by the Vermont Department of Fish and Game. The depot at the east end of the bridge was torn down in the 1960s. In 1972 the Vermont Division for Historic Preservation took possession of the bridge in order to preserve it.
With the support of a Federal and matching state grant, restoration of the bridge began in the fall of 1983. The contract was awarded to Vermont Structures, Inc. of Middlebury. The abutments were reinforced, a new deck constructed and the roof and siding replaced at a cost of $35,014. The bridge site is presently a popular spot for fishing.
Design
During the 1830s and 40s, demand increased for standardized bridges that could be rapidly erected and easily maintained to keep pace with the growth of the nation's railroad network. In 1840, Massachusetts millwright William Howe (1803-1852) patented a timber truss with parallel upper and lower chords connected by wood diagonals in compression and iron verticals in tension. First to incorporate iron for primary structural members, the Howe truss improved on Colonel Stephen H. Long's design by replacing the vertical wood members with adjustable wrought iron rods to overcome the inherent difficulty of creating tension connections in wood structures and allow for easier and more efficient prestressing of the members. In the case of the Shoreham Bridge, these rods increase in number and dimension toward the end of the trusses where the greatest member forces occur.
Howe's first bridge, a small railroad bridge over the Quaboag River at Warren, Massachusetts "was so successful that Chief Engineer George Washington Whistler of the Western Railroad gave [Howe] the contract for the biggest bridge on the line", an enormous seven-span deck truss bridge across the Connecticut River at Springfield, erected in 1842. The Howe truss soon became the most widely used wooden truss for railroad bridges. Railroad engineer Theodore Cooper stated in 1889: "This form of truss grew rapidly into favor, from its simplicity of construction, perfection of detail and satisfactory action under service. For some years it has been the standard form of wooden bridge in use upon our railroads. ...No better railroad bridge up to 150 feet spans could be desired."
Railroads favored the Howe truss design because it offered the rigidity of the Long truss, but had simpler framing connections and could be erected quickly and adjusted easily. An article in the 1878 Transactions of the American Society of Civil Engineers stated: "The Howe truss may justly be termed the most perfect wooden bridge ever built; others have been designed of greater theoretical economy; but for simplicity of construction, rapidity of erection, and general utility it stands without rival." Used extensively for railroad bridges in the United States and Europe during the mid-nineteenth century, the timber Howe truss gradually gave way to similar structures with cast iron compression members and wrought iron tension members. There are well over 125 examples of timber Howe truss covered bridges surviving in the United States today, although only four of these are railroad bridges.
Surviving Covered Railroad Bridges in the United States
Contoocook Bridge Merrimack County, NH 1889 157' Town lattice truss B&MRR
Sulphite Bridge Merrimack County, NH 1896 180' Pratt deck truss B&MRR
Shoreham Bridge Addison County, VT 1897 109' Howe truss Rutland RR
Clark's Bridge Grafton County, NH 1904 116' Howe truss M&WR RR
Wright's Bridge Sullivan County, NH 1906 124' Town lattice truss B&MRR
Pier Bridge Sullivan County, NH 1907 217' Town lattice truss B&MRR
Fisher Bridge Lamoille County, VT 1908 98' Town lattice truss SJ&LC RR
Harpole Bridge Whitman County, WA 1922 163' boxed Howe truss Great Northern RR
