The construction started with the sinking of the first shovel on June 9, 1967, and continued for six years. (During construction, a giant "Earth mover" working on the canal, accidentally struck and ruptured a buried natural gas line, which erupted into a torch-like flame approx 90–100 meters high; there were no injuries.) In a symbolic event watched by many residents, on a snowy night, Bridge #13 on Welland's East Main Street came up for the last time, lighted by floodlights, on December 15, 1972, the new bypass would be open to shipping for the next season. (The bridge was actually quietly opened the next day to allow the passage of a St. Lawrence Seaway service vessel.)