User:Atomsmith/PRR Draft



The Amtrak Susquehanna River Bridge is a Howe deck truss structure which carries two tracks of Amtrak's Northeast Corridor line across the Susquehanna River between Havre de Grace and Perryville, Maryland.

The structure was built by the Pennsylvania Railroad (PRR) during 1904-1906, opening on May 29, 1906. It includes a center swing span to increase vertical clearance for water traffic from the nominal 52 ft. In 1934-1935, the PRR installed catenary on the span when 11,000 volt electrification was extended south from Wilmington, Delaware to Washington, DC. Regular electrified passenger service across the bridge began on February 10, 1935.

Ownership of the bridge passed to Amtrak in 1976 when it acquired much of the Northeast Corridor infrastructure.

History
The vicinity of the bridge has been in use as a river crossing for over 300 years. In 1695, the colonial General Assembly granted the first licenses to operate a toll ferry service between Perryville and what is now Havre de Grace. In 1837, railroad lines extending south from Wilmington, Delaware and north from Baltimore arrived at the riverbanks. For 29 years, including the duration of the American Civil War, a train ferry exchanged passengers (on foot) and freight cars between the two towns. Passenger cars could not be transported until the introduction of a larger ferryboat in 1854.

In 1866, the wooden, single track Philadelphia, Wilmington, and Baltimore (PW&B) railroad bridge was completed after 12 years of intermittent construction. Iron reinforcements were added between 1874 and 1880. In 1881, the Pennsylvania Railroad formally took control of the PW&B. Rival Baltimore & Ohio Railroad, cut off from access to the PW&B and its links to Philadelphia, was forced to construct a parallel route between Baltimore and Philadelphia, including the Perryville Railroad Bridge located about 1 mi upstream. The present (1906) bridge was built immediately adjacent to the PW&B structure and completely replaced it.

Present status
Approximately 100 Amtrak and MARC passenger trains cross the bridge on weekdays at a maximum speed of 90 mph. Approximately 12 freight trains a day cross at a maximum speed of 30 mph. Freight traffic, operated by Norfolk Southern Railway under a trackage rights agreement, is generally restricted to nighttime hours to avoid interference with passenger operations.

The only significant commercial water traffic under the bridge consists of barges from a large granite quarry just upstream of Havre de Grace. The bridge's swing span rarely needs to be opened; vessels which require such an opening must provide 24-hour advance notice.

In 2005 and 2007, Amtrak replaced the ties on the bridge, installed continuous welded rail, and installed new deck-level maintenance walkways. They believe these changes will extend the life of the bridge for another 20–25 years. In the meantime, Amtrak is seeking capital funding sources to replace the entire structure. The Bush River and Gunpowder River bridges, two spans of similar age on the Northeast Corridor in Maryland, are also under consideration for replacement.