Smiths Falls Bascule Bridge National Historic Site of Canada
Smiths Falls, Ontario
General view
(© Parks Canada Agency/Agence Parcs Canada, 1988.)
Address :
5 Abbot Street, Smiths Falls, Ontario
Recognition Statute:
Historic Sites and Monuments Act (R.S.C., 1985, c. H-4)
Designation Date:
1983-06-13
Dates:
-
1912 to 1913
(Construction)
-
1915 to 1978
(Significant)
Event, Person, Organization:
-
Canadian Northern Railway
(Organization)
-
Canadian National Railways
(Organization)
Other Name(s):
-
Smiths Falls Bascule Bridge
(Designation Name)
Plaque(s)
Existing plaque: Detached Lockstation - 90 m downstream from bridge, near canal locks 5 Abbot Street, Smiths Falls, Ontario
This Scherzer Rolling Lift bascule bridge is an outstanding early example of a novel concept in movable bridges, developed by William Scherzer, an American engineer. It combines the balanced counterweight of a conventional bascule bridge, with a unique rolling lift motion that all but eliminates friction. Erected in 1912-1913 to carry the Canadian Northern Railway main line across the Rideau Canal, a busy steamboat navigation system, the bridge was renowned for its ease and speed of operation, proving the efficacy of the concept.
Description of Historic Place
Smiths Falls Bascule Bridge National Historic Site of Canada is an early movable concrete bridge built in the early twentieth century to carry rail traffic over the Rideau Canal. Located within the town of Smiths Falls, today it stands with its roadbed span permanently raised, its massive counterweight stretching almost perpendicular to the sky, and its adjacent bridge tender's tower unmanned.
Heritage Value
Smiths Falls Bascule Bridge was designated a national historic site in 1983 because this Scherzer Rolling Lift bascule bridge is an outstanding early example of a novel concept in movable bridges.
The heritage value of Smiths Falls Bascule Bridge National Historic Site of Canada resides in its manifestation of a technological achievement as illustrated by its distinctive form, materials and design. The Smiths Falls bascule bridge was built on the Toronto-Ottawa line of the Canadian Northern Railway in 1912-1913. Very little power was required to operate it owing to the unique rolling lift action which almost eliminated friction, and the overhead concrete counterweight which balanced the 21-metre plate-girder lift-span. Originally electrically powered, the bridge was manually operated from 1915-1978. Scherzer rolling lift bascule bridges were introduced to Canada ca. 1911, and this is the oldest surviving structure of its type. Canadian National Railways transferred ownership of the bridge to the City of Smiths Falls for maintenance as a heritage resource in the mid 1980s.
Source: Historic Sites and Monuments Board of Canada, Minutes, 2002.
Character-Defining Elements
Key elements that contribute to the heritage value of this site include:
its location, spanning the Rideau Canal in a formerly busy railway hub; the linear footprint and profile of the bridge with its massive counterweight and bridge tender's tower; the bridge structure with its two-deck plate-girder approach spans resting on concrete piers and abutments with the bascule span in the middle over the navigation channel; the bascule span with its deck-plate girder and overhead counterweight; the counterweight, mounted overhead on two segmental girders curving outwards and upwards from the heel of the deck girder along each side of the lift span; the integrity of the bridge's materials (steel plates and girders, reinforced concrete counterweight); the integrity of its construction technology; the integrity and continued legibility of its lift technology (requiring the girders to roll back along horizontal tracks on the approach span girders; raised teeth on the track girders keep the moving span in alignment as it rolls backward or forward); the integrity of its drive system (gearing system, pinions, shaft, horizontal toothed rack, locking devices); any evidence of its early electric operation and later manual operation; the small elevated bridge tender's tower with its cross braced platform and small, square, wooden, pitch roofed hut on its high platform; viewscapes from the bridge up and down the Rideau Canal, and along the original trackbed.