Welland Canal - City of Port Colborne

Weir Dam – Main Street
The bridge was built as part of the fourth Welland Canal, replacing
a swing bridge over the first, second, and third canals at the same
site. The dam beneath this bridge regulates the amount of water
downstream in the canal, including seven lift locks stretching to
Lake Ontario and a hydro-electric generating plant at Decew Falls in
St. Catharines.
The railway swing bridge, built in 1880s, with Canadian National Railway
marking on the side.
The Island
North of Clarence Street, the first three canals followed the west
channel. This route made use of an old creek that passed through
the village of Stonebridge, later named Humberstone. The natural
watercourse was widened several times and augmented by
limestone blocks serving as retaining walls.
Weir dam at Main Street West.
Lock 8 and Lock 8 Gateway Park
Lock 8 on the east side of the Island serves as a guard lock for the
canal, raising or lowering ships one to four feet, depending on the
Lake Erie water levels. At 420 metres, it is one of the longest canal
locks in the world. Being the southernmost lock on the present-day
Welland Canal, many ships use time in the lock to have supplies
replenished, switch crew, and undergo minor repairs.
South point of “The Island”- weir channel to left, lock 8 to right.
Early in the 20th century it became feasible to blast through
bedrock and construct a straighter, more direct eastern channel.
It was accomplished in 1932 with the construction of the current
Welland Canal. The area surrounded by the east and west canal
channels is known locally as “The Island.” It was created by the
cutting of the new fourth canal channel in the 1920s and the
existence of the curved first, second, and third canal channels,
thereby surrounding the entire area with water. Access to The Island
from the east must be made by either of the jack-knife bridges at
Lock 8. From the west, The Island can be accessed over the weir
control structure at Main Street West, the weir crossing at Killaly
Street West, or the pedestrian bridge at Derek Point. The western
crossings pass over the route of the first, second, and third canals.
Ship entering lock 8, under jack-knife bridge (Bridge 19).
Lock 8 Gateway Park, adjacent to Lock 8 has an elevated viewing
platform to watch ships enter and exit the lock. The single-leaf
rolling bascule, or jack-knife bridges at each end provide vehicle
access to “The Island” and the east and west sides of the City.