Amtrak Bascule Bridge No. 116.74 over the Niantic River, between East Lyme and Waterford, Connecticut. The bridge is located along Amtrak’s busy Northeast Corridor.
One of the most complex capital projects, partially funded by the American Recovery and Reinvestment Act, the Niantic River Bridge is an Amtrak-owned century-old bridge that serves as a key link for passenger and freight rail traffic between New York and Boston. Because it is no longer economical to repair the bridge, it requires full replacement to provide reliable rail operation. Its replacement will enable Amtrak to increase speeds on and near the bridge and minimize traffic and delays. Construction is scheduled to be completed in May 2013.
The new Niantic River Bridge will replace one of the oldest movable bridges in the country, a two-track, bascule (rolling lift) bridge that was built in 1907, which has been in continuous operation ever since. The bridge is one of five movable bridges along the Northeast Corridor rail line between New Haven, Conn. and Boston, Mass.
The project involves the construction of a new two-track, electrified railroad bascule bridge across the Niantic River 58 feet south of its present location between East Lyme and Waterford, Connecticut.
Major work elements include: construction of new track alignments on both the East and West Approaches to the bridge; expansion of the navigation channel beneath the bridge from 45 feet to 100 feet; and an increase in the vertical under-clearance above the water from 11.5 feet to 16 feet. In addition, sections of the Niantic Bay Overlook boardwalk will be reconstructed and the beach replenished. Once the new bridge is constructed and operational, the existing bridge will be removed.
In order to build the new three-span railroad bascule bridge 58 feet south of the existing bridge, track along both the West and East Approaches to the bridge must be realigned. The West Approach work will entail track construction, embankment construction, scour protection, retaining walls and reconstruction of the boardwalk. The East Approach work will also entail track construction, embankment construction, scour protection, and retaining walls, A new electrification system used to power the trains will also be built.
The existing Niantic Bay Boardwalk will be relocated due to the new track alignment on the West Approach. The existing stone dust walkway will be disturbed from excavation but will be restored to existing conditions afterward. The existing wooden boardwalk will be removed and replaced with a concrete walkway. The existing sidewalk that passes under the existing bridge’s westernmost span will be demolished and rebuilt to a new alignment to connect the boardwalk to East Lyme’s Cini Park.
The U.S. Coast Guard has jurisdiction over channel navigation and navigational safety related to the Niantic River Bridge. Channel navigation will be maintained as feasible throughout the Niantic River Bridge Replacement Project. Specific channel navigation Information will be regularly updated and posted on this site during construction. The U.S. Coast Guard will issue Notice to Mariners advising of any channel closures and these will be posted on this web page. Any changes to the normal bridge opening procedures will also be disseminated through these channels.
The existing timber fender system and three existing, abandoned piers that are in the Niantic River that date from an old 1800s swing bridge will also be removed. The existing bascule bridge provides a navigational channel of 45 feet horizontal clear width, with 11.5 feet of vertical underclearance to Mean High Water (MHW) in the bridge closed position, and unlimited vertical clearance in the bridge open position. The new replacement bridge will provide a navigation horizontal clearance of 100 feet between proposed fenders, with an increased vertical underclearance in the closed position to 16 feet above MHW, and a vertical clearance in the open position of 75 feet at the most restricted edge of the channel (for most of the proposed 100-foot channel, the clearance will be unlimited).
The proposed 100-foot wide channel will match the present U.S. Army Corp of Engineers Navigation Channel Project width of 100 feet, both upstream and downstream of the bridge. The project will also include installation of new submarine cables for bridge power and controls, for railroad communication and signals and for railroad electric traction power. In addition to permanent cable installations, allowance has been made for temporary railroad electric power cables during construction of the new bridge. A channel closure period of one week in 2012 is anticipated for float-in and erection of the new bascule span. An additional, separate three-day closure period is anticipated to take place in 2012, for removal and float-out of the existing bascule span during demolition.
One of the most remarkable projects of the King Movable Bridge Company was "Old Nan" across the Niantic River between Niantic and Waterford, Conn. It is the oldest of the five movable bridges still operating on the rail line between Boston and New York and is used daily by Amtrak Acela high-speed trains. The bridge was built in 1907 to replace a swing-span bridge and has been in continuous operation ever since.
For questions or comments concerning this project, call Amtrak at the toll free hotline 1-800-288-1310 or e-mail us at askamtrak@amtrak.com.
