Science Fair Project Encyclopedia
The Sault Locks (usually called the Soo Locks) allow ships to travel between Lake Superior and the lower Great Lakes. The locks are the busiest in the world, passing an average of 12,000 ships per year. This is achieved in spite of the locks being closed during the winter months, January through March, when ice shuts down shipping on the Great Lakes. The winter months are used to inspect and maintain the locks.
The locks bypass the rapids of the St. Marys River where the water falls 7 meters (21 feet) from Lake Superior. St. Mary's Rapids, in French Sault Ste. Marie, gives its name to both the Canadian and American cities at the site. The Sault Ste. Marie International Bridge between the United States and Canada permits vehicular traffic to pass over the locks.
Since the 1980s, an invasive species of mussel known as Zebra mussels have been multiplying in the Great Lakes. Likely introduced via the ballast water of foreign ships entering the lakes through the locks, they kill native fish, crowd out other native species, and encrust piers, ships, and pipes. Revised shipping regulations have been designed and are currently under consideration to prevent the introduction of other non-native species to the Great Lakes ecosystem.
The American locks form part of a 1.6 mile (2.6 km) canal formally named the St. Mary's Falls Ship Canal. They are owned and maintained by the United States Army Corps of Engineers. The first American locks were completed in May 1855.
Davis Lock was built in 1914. It is 411 meters (1350 feet) long, 24 meters (80 feet) wide and 7 meters (23 feet) deep. It is now closed because it is too shallow for the modern ships that use the locks.
Sabin Lock was built in 1919. It is also closed because it has the same dimensions as the Davis Lock.
MacArthur Lock was built in 1943. It is 244 meters (800 feet) long, 24 meters (80 feet) wide and 9 meters (31 feet) deep. This is large enough to handle ocean going vessels that must first pass through the smaller locks in the Welland Canal.
Poe Lock was re-built in 1968, after the Saint Lawrence Seaway had opened. It is 366 meters (1200 feet) long, 34 meters (110 feet) wide and 10 meters (32 feet) deep. It can take ships carrying 72,000 tons of cargo. The Poe is the only lock that can handle the large lakers used on the upper lakes.
Canadian lock, the only lock on the Ontario side, was built in 1895. It broke down in 1987 and a new lock was built within the old lock. The lock was reopened in 1998 and is used for recreation and tour boats. It is 76 meters long, 16 meters wide and 3 meters deep.
The Sault locks are a well developed tourist site that offers viewing stands to watch the locks at work and tour boat trips through the locks. There is also a Soo Locks Festival.
There is a project, as yet unfunded, to built a new large lock to replace the unused Davis and Sabin locks.
The contents of this article is licensed from www.wikipedia.org under the GNU Free Documentation License. Click here to see the transparent copy and copyright details