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Strategic plan targets invasive species
The Superior Daily Telegram (11/17)
Douglas County’s Land Conservation Committee is forwarding a plan to the county board that takes aim at invasive species.

Mich. Clean Marina Program: Public-private partners work together to improve water quality
Grand Rapids Environmental News Examiner (11/9)
Partners from the public and private sector in Michigan are working together in a voluntary program to improve the quality of the Great Lakes.

Researchers seek funding for wind test site in Lake Michigan
Grand Rapids Environmental News Examiner (11/7)
In a recent article in The Muskegon Chronicle, it was reported that researchers at Grand Valley State University’s Michigan Alternative and Renewable Energy Center (MAREC) cited a lack of year-around data (on wind platform testing) needed by prospective development companies.

COMMENTARY: Senate needs to pass clean energy act to help Michigan
The Grand Rapids Press (10/26)
Senate Majority Leader Harry Reid was absolutely correct with his recent proclamation about the current condition of the Great Lakes State: "The State of Michigan," Reid declared from the Senate Floor, with a copy Time Magazine in his hand, "is in trouble."

First Nation women 'walk the environmental talk'
WeNews (10/23)
Tomorrow's global day of climate activism aims for media and political attention. First Nation women have another way. Since 2003, they've walked the shoreline of a Great Lake or major river, meditating on the needs of an unborn generation.

City making big push for water school
The Business Journal (10/23)
The push is on to convince the University of Wisconsin-Milwaukee that the best location for its new School of Freshwater Sciences is near the university’s existing Great Lakes Water Institute on East Greenfield Avenue.

TEACH Calendar of Events
What's going on in your neighborhood this month? Meet other people and learn together at recreational and educational events! Our new dynamic calendar is updated daily with current educational events.
TEACH Questions & Answers

If the St. Lawrence River connects the Great Lakes to the Atlantic Ocean, why aren't the Great Lakes saltwater instead of freshwater?
from Billie Rae in Summerville, South Carolina, Age 12

Great question!

The St. Lawrence River can be divided into three broad sections: the freshwater river, which extends from Lake Ontario to near 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.

View a map of the St. Lawrence river region
View a map of the entire Great Lakes-St. Lawrence River system

Originating from Lake Ontario near the Canadian town of Kingston, the St. Lawrence River is freshwater until near the Canadian town of Donnacona in Quebec. In this section, the river is always freshwater and flowing in the direction of the Gulf, or downstream. There are many tributaries that flow into the river, such as the Ottawa and Chateauguay Rivers. Because the water flow is quite fast in this part of the river, the water from the tributaries is kept from entering the center of the St. Lawrence River; this phenomenon creates two separate water masses that flow beside one another for a long distance before mixing completely.

After Donnacona, the river widens considerably and enters the brackish water zone, the area where freshwater and saltwater meet. In this section, the salinity of the water rises from zero to twenty percent! Tidal influences from the Atlantic start to affect the river, and the river becomes an estuary, with one of its main tributaries being Saguenay River. An estuary is where a freshwater river current meets an ocean tide, and is often abundant in wildlife. The St. Lawrence estuary is over 300 miles long, and is one of the most productive marine ecosystems along the Canadian coast. Over 718,000 seabirds of 19 species, such as the Atlantic puffin, the red-throated loon, and the Artic tern, and several different species of whales, such as finback, minke, Beluga, sperm and blue whales, are found in the St. Lawrence estuary.

The estuary deepens considerably as it heads toward the ocean, with the depth increasing from around 80 feet (25 meters) to 1,145 feet (358 meters). Once the waterway passes by Anticosti Island, the estuary becomes known as the Gulf of St. Lawrence. The Gulf extends 250 miles from the St. Lawrence River estuary to Newfoundland, where it becomes the Atlantic Ocean, and at its greatest width the Gulf is 500 miles (800 km) wide.


References:
St. Lawrence River and Seaway, Encyclopedia Britannica
The Hydrology of the St. Lawrence Basin, Canada's Digital Collections
The Seabirds of the St. Lawrence, Environment Canada

Maps:
St. Lawrence Region, College of Communication, University of Illinois
St. Lawrence Hydrographic System, Encyclopedia Britannica

Thank you for your question!


Answered on September 1, 2000

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