Description of Historic Place

St. Andrews Caméré Curtain Bridge Dam is a 270 metre-long bridge-dam spanning the Red River at Lockport, Manitoba. The bridge supports a movable dam consisting of a series of Caméré curtains which maintain the river at a navigable depth during the summer months and are rolled up and removed each fall to enable the spring flood waters to pass unimpeded under the bridge. A canal lock, constructed in the west bank adjacent to the bridge-dam, carries river traffic past the dam. Today the bridge-dam remains in service on provincial Highway #44.

Heritage Value

St. Andrews Caméré Curtain Bridge Dam was designated a national historic site of Canada because this engineering work is perhaps the only surviving moveable dam of its type in the world.

The heritage value of this site is carried in the design and materials of the structure itself. Erected by the Federal Department of Public works between 1907 and 1910, it is the largest of its type ever constructed. In 1912-1913, approach spans were added and a roadway built across the bridge-dam. The approaches were modified and loading capacity increased in 1947-1949. New frame and curtain cranes replaced the originals in 1967. By that time railway and road transport had largely replaced water transport, severely reducing the commercial use of the river and canal system.

Source: Historic Sites and Monuments Board of Canada, Minutes, November 1990.

Character-Defining Elements

Key elements of this structure include:
- the location over former rapids in the Red River;
- the current 240.1-metres length between abutments;
- the dam design as a movable weir;
- its division into six 36.3-metres, 0.2 metre-wide bays by five concrete piers interconnected at their base;
- the original 270-metres long bridge superstructure consisting of 7 truss spans and a deck truss with upper chords carrying a road and lower chords supporting a suspended floor and a working floor for the curtain dam;
- the electrically powered frame cranes running on a trolley track along the working floor to raise and lower the hinged curtain frames and smaller curtain cranes mounted on a truck on tracks;
- the steel shoes set into the submerged dam serving as a sill for the movable component;
- 90 wooden curtains hooked onto the curtain frames;
- the concrete lock and dam substructure;
- the solid timber mitre gates;
- the steel Pratt bridge trusses;
- the concrete and steel Strauss bascule bridge;
- the existence of a vehicular road-deck.