St Mary's Canal - Lock Station

[Manfred M]

Another shot from a trip to Sault Sainte-Marie. This is the St Mary's Canal, which opened in 1895 (and was rebuilt in 1987) and was used to bypass the rapids in the river that connects Lake Huron and Lake Superior. It is a National Historic Site.

[Dave Humphries]

Hi Manfred,

I am puzzled by the two pairs of lock gates so close together, surely too close to fit a boat/ship/barge in between them!

I'm not sure I see the benefit of using both pairs at same time, or is one pair a backup for the other, in case of failure/damage?

Good photo though,
Dave

[Manfred M]

Hi Manfred,

I am puzzled by the two pairs of lock gates so close together, surely too close to fit a boat/ship/barge in between them!

I'm not sure I see the benefit of using both pairs at same time, or is one pair a backup for the other, in case of failure/damage?

Good photo though,
Dave

My suspicion is that these are "guard locks" which are closed in the winter to prevent ice damage to the canal itself. The canal is drained at the end of the season (this canal is now only used for pleasure craft), with the large "lakers" and ocean going vessels using the Soo Locks, that are on the USA side of the river.

The actual lock; which is the white area that one can see at the end of the image has a drop of around 6.3m / 21 ft.

Here is an aerial view of the canal. The place I am photographing from is just to the right of where the waterway narrows at the left hand side of the image. The actual locks can be seen the right hand side.




The arrangement is similar to the Rideau canal segment that runs through Ottawa, Canada. There is a guard lock at Mooney's Bay and the entire section of the canal is drained between Mooney's Bay and the Ottawa River.

[Tom Barry]

Impeccable photography, of course, and an interesting discussion on canal technology and history.

[Manfred M]

This is a shot of the Rideau Canal after it has been drained. The navigation buoys (red and green) can be seen lying on the bottom. The 8 km section where people skate during the winter starts a bit past the Orthodox Church in the background, so the water level is not completely empty in that part, but is much lower than when it is used for boating traffic (early June through the middle of October)





Same general view of the canal a few days earlier before the water level was dropped.

[pschlute]

We have a number of old and much smaller canals around where I live in Surrey, UK. Plenty of locks of course. There is one in particular where the name is Walsham Gates. Note, it is not called a lock. The purpose of the "gates" is in high water (the canal at this point is also fed by a river) the gates can be shut sending the excess water over the weir to join the river, rather than be fed down the canal.

This means that the normal position for the "gates" is for both to be open, unlike a lock. Not dissimilar to the gates in Manfred's photo but for different reasons.

[Manfred M]

We have a number of old and much smaller canals around where I live in Surrey, UK. Plenty of locks of course. There is one in particular where the name is Walsham Gates. Note, it is not called a lock. The purpose of the "gates" is in high water (the canal at this point is also fed by a river) the gates can be shut sending the excess water over the weir to join the river, rather than be fed down the canal.

This means that the normal position for the "gates" is for both to be open, unlike a lock. Not dissimilar to the gates in Manfred's photo but for different reasons.

Very similar to the way that the Rideau Canal section that runs through downtown Ottawa works.

The canal itself uses natural waterways with lock stations to connect the Ottawa River to Lake Ontario, except for the last few kilometers at the Ottawa end of the canal. Here a man-made section starts at Mooney's Bay, while the Rideau River goes its separate way to join the Ottawa River at the Rideau Falls, some 1.6 km 1 mile from where the canal ends at the foot of the Canadian Parliament Buildings.

A dam controls the water level at Mooney's Bay through the weir shown in this image. This set of rapids is called the Hogs Back Falls.





I am pointing my camera in the opposite direction to the images in #5; there are just a few metres / yards separating the river and canal at this point.

[Wavelength]

Beautiful images; splendid colours!!!