During my visit to Michigan's Upper Peninsula, I learned a lot about shipping on the North American Great Lakes. One of the most fascinating places I visited was the Soo Locks of Sault Saint Marie. As folks may be aware, Sault Saint Marie is an international border city between the United States (Michigan) and Canada (Ontario). Visitors on either side can observe the locks from open platforms that are right along side the waterway.
For my visit to the Soo Locks, I enjoyed taking the Soo Locks Boat Tours' Sunset Dinner Cruise which not only included a nice buffet dinner, but also a full tour of the locks on both the US and Canadian side. Check out my full review of that experience, included in this journal. Here, I really want to focus on the Soo Locks, their purpose and how they function.
When people talk about the Soo Locks, all vessels are either going "up" towards Marquette, MI; Superior, WI; Duluth, MN or points in between. Those going "down" are heading towards any number of ports along the other Great Lakes of Michigan, Huron, Erie or Ontario. Actually, it is possible for a ship to pass through the locks here enroute on to the Atlantic Ocean. Those heading to the ocean are also known as "Salties." It is an amazing feat of innovation that it is possible for ships to make their way as far inland as Minnesota via the Great Lakes.
The general scientific principle behind the locks is that water levels must be equalized in order for passage from one body of water to another. Between Lakes Superior and Huron is the St. Mary's River. The river is 21 feet lower than the level of Lake Superior, which requires creating a means to safely travel between the two, whether heading up or down.
So heading up, we entered the American Soo Locks which are operated by the US Army Corps of Engineers. The MacArthur Lock is the one closest to the dock and viewing area and the one many vessels are directed to. It was also the one our "little" dinner cruise boat used to head up. At 800 feet in length, however, it is not large enough to handle some of the larger lake freighters (also known as "lakers"). Those large freighters would be directed to the Poe Lock which is 1200 feet in length.
As we headed into the MacArthur Lock, the doors closed in behind our boat. We were met port-side by a dock hand who would tie us down to the dock above us. This is done to prevent the boat from rocking or becoming unstable within the lock. With us secured, water is allowed to flow into the lock from Lake Superior in front of us. The water comes in under its own momentum due to gravity. As the water enters the lock, the water level is raised.
After about 15 or 20 minutes, the water level has been raised the 21 foot differential between St. Mary's River and Lake Superior. With our boat now at the same level as Lake Superior before us, the ropes holding us to the dock are released. Next the front gate opens and we are permitted to proceed forward into Lake Superior.
After traveling some distance forward, we turned towards the Ontario, Canada shoreline and headed for the Canadian Soo Locks. Only smaller recreational boats, under 250 feet in length can use this lock.
The same general principle applies in that we were in higher water levels on the Lake Superior side and must enter the lock in order to have water drained to take us to the lower St. Mary's River levels in order to proceed.
On our trip back down, we shared the lock with a decent sized sailboat. It was really cool to see us both sitting up high, dockside level. As the water was allowed to flow out of the lock into the river, both boats seemingly disappeared below the dock level. Once we were at the river's water level, the gate opened and we were allowed to proceed down the St. Mary's River.
I have to tell you, this was the coolest thing ever!
For those interested in observing the large ship pass through the locks, you will want to check out this website (http://www.boatnerd.com/) to know when they are scheduled to pass. Here is a sample of what the log looked like on the day of my visit:
August 2 (Friday):
Lee A. Tregurtha Down 04:15 Ore from Marquette
Stewart J. Cort Down 11:30 Ore from Superior
Edwin H. Gott Down 13:05 Ore from Two Harbors
Algowood Up 00:55 Light to Superior
Algoma Guardian Up 03:45 Light to Thunder Bay
Herbert C. Jackson Up 06:05 Stone to Marquette
Algosar Up 17:25 Arrive Soo, Ontario
Edgar B. Speer Up 18:00 Light to Two Harbors
Kaministiqua Up 22:30 Light to Duluth (SMET)
Of particular interest in this manifest are a couple of freighters. The Lee A. Tregurtha was loading at the ore docks of Marquette, MI on Thursday while I was there. I took several photos of her taking on cargo for her trip down.
While at the harbor to take the Soo Locks Tour Dinner Cruise on Friday evening, I observed and photographed the Edgar B. Speer heading up empty to Two Harbors, MN. I also got photos of her as she passed by on St. Mary's River.
Here is the link to the Sault Saint Marie website which includes hours and other useful information necessary to plan your trip to the Soo Locks: http://www.saultstemarie.com/member-profile/3/1/ .