Ottawa River drainage basin
The Ottawa River drainage basin is the drainage basin in northern North America where surface water empties into the Ottawa River and adjoining waters. Spanning an area of about , it is the 12th largest drainage basin in Canada, occupying the Canadian provinces of Ontario and Quebec. It accounts for about 11% of the total Saint Lawrence River drainage area.
Great Lakes Waterway
Its principal civil engineering works are the Welland Canal between Lakes Ontario and Erie, and the huge Soo Locks between Huron and Superior. Dredged channels were constructed in the St. Marys River, the Detroit River, Lake St. Clair and the St. Clair River between Huron and Erie. Usually, one or more U.S. Coast Guard icebreakers help keep the water passage open for part of the fall and early winter, although shipping usually ceases for two to three months thereafter. The Great Lakes Waterway is co-administered by the governments of Canada and the United States of America.