RECL completed the construction a new lock and bridge, north of the old locks, in Smiths Falls, under contract with the Department of Indian Affairs and Northern Development, in 1974. The new lock, numbered 29a (since it replaced locks 28, 29 and 30), had a lift of 26 feet (7.9m), the highest lift of any lock on the Rideau. It was electrified, the gates being opened and closed with the use of electric-hydraulic cylinders. Boaters now pass beneath a high level fixed bridge with 26 feet (7.9m) of clearance before entering the new combined lock.
Architect: Department of Indian and Northern Affairs