The St. Lawrence River and Seaway is of vital geographic and economic importance to the Great Lakes system, connecting the lakes to the Atlantic Ocean and providing navigation to deep-draft ocean vessels. Approximately 800 miles (1,287 km) long, the St. Lawrence River can be divided into three broad sections: the freshwater river, which extends from Lake Ontario to just outside the city of Quebec; the St. Lawrence estuary, which extends from Quebec to Anticosti Island; and the Gulf of St. Lawrence, which leads into the Atlantic Ocean.
The St. Lawrence River drops 226 feet between Lake Ontario and Montreal, Canada. To allow vessels to pass through the river and in and out of the Great Lakes, the St. Lawrence Seaway, a massive American-Canadian navigational project, was begun in 1954 and completed in 1959. The Seaway created the final link in the Great Lakes-St. Lawrence River system, connecting Duluth, Minnesota, some 2,340 miles (3,766 km) away, with the head of the Gulf of St. Lawrence, through a complex system of lakes, rivers, deepened channels, locks, and canals.
St. Lawrence River at Cornwall AOC Environment Canada The St. Lawrence River at Cornwall Area of Concern (AOC) extends from the Moses-Saunders Power Dam at Cornwall to the Beauharnois Power Dam in Quebec.
St. Lawrence River at Massena AOC U.S. Environmental Protection Agency (EPA) The St. Lawrence River at Massena Remedial Action Plan (RAP) addresses an Area of Concern (AOC) within the legal boundaries of New York state.
Great Lakes St. Lawrence Seaway Study The Canadian and U.S. governments are conducting a joint study to evaluate the infrastructure needs of the Great Lakes St. Lawrence Seaway system, specifically the engineering, economic and environmental implications of those needs as they pertain to the marine transportation infrastructure on which commercial navigation depends.
St. Lawrence Centre Environment Canada The SLC is involved in a multitude of studies and research programs aimed at better understanding how the ecosystems of the St. Lawrence River function and to keep this knowledge up to date.
St. Lawrence Observatory Fisheries and Oceans Canada This web portal is dedicated to the exchange, dissemination and presentation of data collected in the St. Lawrence marine ecosystem. Includes aerial views, current monitoring efforts, models, animations and more.
The Biosphère Environment Canada Opened in 1995 as the only museum of water in America dedicated to the St. Lawrence River and the Great Lakes, the Biosphère heightens public awareness of water's importance and the necessity to protect it.
The Lake Ontario-St. Lawrence River Study International Joint Commission Specific studies include the effects of water level fluctuation on wetlands, tourism, coastal zone, navigation, energy, and municipal water uses.
Publications Le Fleuve Saint-Laurent Vision 2000 An online newsletter aiming to inform people, organizations or companies interested in the protection and the conservation of the St. Lawrence River.
Tourism The Great Lakes Circle Tour Ride along on the 6,500-mile Great Lakes Circle Tour: a scenic, international road system connecting the five Great Lakes and the St. Lawrence River! For new visitors to the region, this online travel guide offers informational maps, road routes and estimated mileages, and links to major cities, camping and recreation areas, and natural attractions.
New York State's Seaway Trail The New York State Seaway Trail is a 454-mile scenic route paralleling Lake Erie, the Niagara River, Lake Ontario and the St. Lawrence River.