The Lyman Viaduct is a buried railroad trestle built over Dickinson Creek in

Colchester, Connecticut Colchester is a New England town, town in New London County, Connecticut, United States. The town is part of the Southeastern Connecticut Planning Region, Connecticut, Southeastern Connecticut Planning Region. The population was 15,555 at the 20 ...

, in 1873. Along with the nearby Rapallo Viaduct, it is one of the few surviving

wrought iron Wrought iron is an iron alloy with a very low carbon content (less than 0.05%) in contrast to that of cast iron (2.1% to 4.5%), or 0.25 for low carbon "mild" steel. Wrought iron is manufactured by heating and melting high carbon cast iron in an ...

railroad trestles from the first generation of such structures. It was built for the

Boston and New York Air-Line Railroad The Boston and New York Air-Line Railroad (commonly known simply as The Air Line, known as the New Haven, Middletown and Willimantic Railroad before 1875) was a railroad in Connecticut. Envisioned as a direct route between New Haven and Boston, i ...

, whose successor, the

New York, New Haven and Hartford Railroad The New York, New Haven and Hartford Railroad , commonly known as The Consolidated, or simply as the New Haven, was a railroad that operated principally in the New England region of the United States from 1872 to 1968. Founded by the merger of ...

(NYNH&H), buried it in sand rather than replacing it with a stronger structure. The bridge was added to the

National Register of Historic Places The National Register of Historic Places (NRHP) is the Federal government of the United States, United States federal government's official United States National Register of Historic Places listings, list of sites, buildings, structures, Hist ...

in 1986 since it is capable of providing detailed information about construction methods of the period. The bridge now carries the multi-use

Air Line State Park Trail Air Line State Park Trail is a rail trail and linear state park located in Connecticut. The trail is divided into sections designated South (a 25-mile trail from East Hampton to Windham), North (a 21-mile trail from Windham to Putnam) a piec ...

.Connecticut Department of Energy & Environmental Protection
"Air Line State Park Trail: Overview."
Accessed 2012-11-25.

Description and history

The Lyman Viaduct is located in a rural setting of northwestern Colchester. Its center is about west of Bull Hill Road on the state-maintained Air Line Trail. It is a

post Post, POST, or posting may refer to: Postal services * Mail, the postal system, especially in Commonwealth of Nations countries **An Post, the Irish national postal service **Canada Post, Canadian postal service **Deutsche Post, German postal s ...

deck truss A truss bridge is a bridge whose load-bearing superstructure is composed of a truss, a structure of connected elements, usually forming triangular units. The connected elements, typically straight, may be stressed from tension, compression, or s ...

design, long with a maximum height of . The structure consists of bents formed out of three quarter-round rolled wrought iron sections, with flanges designed to facilitate riveted assembly. At the stream crossing point, there are four columns. Each tier of the trestle is joined horizontally and laterally to adjacent members. The entire structure is buried in earthen fill and topped by a dense pack of cinder blocks, now somewhat overgrown on the sides. With . The bridge was built in 1873 by the Phoenix Iron Works for the

, which aimed to provide service between

New York City New York, often called New York City (NYC), is the most populous city in the United States, located at the southern tip of New York State on one of the world's largest natural harbors. The city comprises five boroughs, each coextensive w ...

and

Boston, Massachusetts Boston is the capital and most populous city in the Commonwealth (U.S. state), Commonwealth of Massachusetts in the United States. The city serves as the cultural and Financial centre, financial center of New England, a region of the Northeas ...

, via

Middletown, Connecticut Middletown is a city in Middlesex County, Connecticut, United States. Located along the Connecticut River, in the central part of the state, 16 miles (25.749504 km) south of Hartford, Connecticut, Hartford. Middletown is the largest city in the L ...

. The trestle was one of the largest single capital expenses of the railroad venture, which was beset by cost overruns and failed after just ten years of operation. Taken over by the NYNH&H, the trestle was filled as a comparatively inexpensive means of strengthening the structure for use by heavier equipment in the early 20th century. The line remained in operation into the 1960s, and has since been adapted as the multiuse Air Line Trail by the state. This trestle and the nearby Rapallo Viaduct, which was similarly buried, were among the world's first examples of wrought iron railroad trestles, and are the only known ones of that period that are believed to be in good condition, due to their entombment. The only earlier known examples of this technology include the Verrugas Bridge in

Peru Peru, officially the Republic of Peru, is a country in western South America. It is bordered in the north by Ecuador and Colombia, in the east by Brazil, in the southeast by Bolivia, in the south by Chile, and in the south and west by the Pac ...

, begun before these, completed in 1873, and washed away in 1889, and the

Kinzua Bridge The Kinzua Bridge or the Kinzua Viaduct (, ) was a Rail transport in the United States, railroad Trestle bridge, trestle that spanned Kinzua Creek in McKean County, Pennsylvania, McKean County in the U.S. state of Pennsylvania. The bridge was ...

Pennsylvania Pennsylvania, officially the Commonwealth of Pennsylvania, is a U.S. state, state spanning the Mid-Atlantic (United States), Mid-Atlantic, Northeastern United States, Northeastern, Appalachian, and Great Lakes region, Great Lakes regions o ...

, later rebuilt in steel. Because records of its construction are incomplete, forensic analysis of the structure (for example, by excavating a portion of the embankment) is expected to provide significant information about its design and construction, in particular how its construction may have deviated from known plans.

References

Bridges completed in 1873 Railroad bridges on the National Register of Historic Places in Connecticut Bridges in New London County, Connecticut Colchester, Connecticut New York, New Haven and Hartford Railroad bridges Railroad bridges in Connecticut Truss bridges in the United States National Register of Historic Places in New London County, Connecticut Wrought iron bridges in the United States Trestle bridges in the United States Buried viaducts

Description and history

See also

References