A water race is a "watercourse constructed to convey water," which suggests that the headrace was specifically built for the purposes of bringing water to the Lachine Canal.
Montreal also had a tailrace further west near the canal, which is defined as a "water channel below a dam or water mill." Coolopolis has written about the tailrace but this is the first we've become aware of its counterpart in Cote St. Paul.
The photos, taken in 1964 by City of Montreal bureaucrats, were shot in order to maintain a record of sites facing pending demolition, which indicates that the buildings and waterway were erased from the map soon after.
The makeshift bridges included one with a roof and were not required to be built at any particular height because no boats or ships were required to travel down the waterway. The purpose of the headrace isn't entirely evident, unlike the basins of Basin Street, as discussed previously on Coolopolis.
Newspapers only make one clear reference to the tailrace, as on 9 July 1921 when The Gazette reported that Barnard Dempsey of Lachine drowned trying to swim across it (an earlier report called him Albert Dempsey, 38, and that his last words to his helpless friends were: "Hold my hat and coat I'm going to jump into the canal.")
This 1964 photo is described as being at 5296 St. Patrick Street, now an empty field. The head race would have been near its backyard.
