General Info

The five Great Lakes lie upstream of the St. Lawrence. The water flows east from Lake Superior, through Lake Michigan, Lake Huron, Lake Erie and finally Lake Ontario, where it flows out into the St. Lawrence. Running from Lake Superior to the Cabot Strait, over a distance of 3,260 km, the St. Lawrence hydrographic system is the 17th longest in the world. The waters descend to the Atlantic Ocean from an altitude of 183 metres, equivalent to the height of a 60-story building. The Great Lakes-St. Lawrence basin contains 25% of the world's fresh water.

The Quebec portion of the St. Lawrence has 244 tributaries, and around 60% of the province's population lives along its shores. The salinity of the water changes significantly as it flows downstream, going from fresh water to salt. The fluvial section and fluvial estuary contain fresh water, which becomes brackish in the upper estuary. The salinity increases from 0.02% near Île d'Orléans to 2% at La Pocatière. The lower estuary has salinity ranging between 2.5% and 3%. The gulf, a true inland sea, has a salinity of 3.2%, very close to the 3.5% salinity found in the Atlantic Ocean.

The St. Lawrence is divided into 5 sections with distinctive features. As the water flows downstream, it passes through the fluvial portion (A), the fluvial estuary (B), the upper estuary (C), the lower estuary (D) and the gulf (E).

The fluvial portion starts after Lake Ontario and runs until the downstream end of Lake Saint-Pierre, where the fluvial estuary begins. It flows to the eastern tip of Île d'Orléans. Here we hit the upper estuary, which extends to the mouth of the Saguenay River on the north shore and to the western tip of Île Verte on the south shore. The lower estuary runs from the Saguenay River to Pointe-des-Monts. At Pointe-des-Monts, the St. Lawrence widens to over 50 km, marking the start of the gulf. This is a transitional zone between the river and the Atlantic Ocean.

The Gulf of St. Lawrence flows into the Atlantic Ocean, between Nova Scotia and Newfoundland. The Laurentian Channel is a natural channel, over 400 metres deep in some places, that runs from the ocean into the gulf. It crosses the gulf and the lower estuary, ending abruptly at the mouth of the Saguenay River. Here, at the boundary between the upper and lower estuaries, the bed of the St. Lawrence suddenly rises to a depth of only 100 metres. The change in depth brings cold, nutrient-rich water to the surface, creating ideal conditions for microscopic algae and the small crustaceans, or krill, that feed on it. Great numbers of fish and whales are attracted to this abundant food source. In fact, many tourists visit this part of the St. Lawrence in hopes of spotting these majestic marine mammals.

There are no tides in the fluvial section. This part of the St. Lawrence is known for its turbulent waters, which create rapids in the narrower stretches. The current can reach a speed of 4 m/s.

The fluvial portion includes three shallow fluvial lakes. From west to east, these widenings of the river are known as Lake Saint Francis, Lake Saint-Louis and Lake Saint-Pierre. The latter is the last fluvial lake before the estuary, and has the largest surface area. The average depth is 5.7 metres in Lake Saint Francis, 3.4 metres in Lake Saint-Louis and just 2.7 metres in Lake Saint-Pierre. The water in these lakes is nearly stagnant and in certain bays, the current flows at less than 0.1 m/s.

The estuary lies between the river and the gulf. The fluvial estuary, also known as the freshwater estuary, is subject to tides. At the outflow of Lake Saint-Pierre, very weak tides can be observed. Downstream of Portneuf, they grow much stronger. When the tide comes in the current is reversed, and water flows back upstream toward the Great Lakes.

The upper estuary is also referred to as the brackish estuary. Here, the fresh water of the river meets the salt water of the gulf. Tides get stronger as the river flows toward the ocean. The upper estuary grows wider downstream of Île d'Orléans; at Île aux Coudres, the north and south shores are 20 km apart.

In the lower estuary, tides are higher and currents are stronger. This section of the St. Lawrence begins at Tadoussac. The Laurentian Channel, a deep natural valley, begins at the confluence of the Saguenay and the St. Lawrence. Here cold, nutrient-rich water from the Atlantic rises to the surface.

The Gulf of St. Lawrence is like an inland sea between the river and the Atlantic Ocean. It features strong currents and large tides. The North Shore, Anticosti Island, the Magdalen Islands and the Gaspé Peninsula all border the gulf.

Navigating the St. Lawrence is quite a challenge. The river features many obstacles: rapids, islands, reefs, shoals, and wide stretches of shallow water. At the confluence of the Saguenay and the St. Lawrence, a unique phenomenon can be observed. Cold, dense water rises to the surface at the end of the Laurentian Channel, then attempts to plunge back down to the riverbed. This creates whirlpools that can destabilize boats. The high walls of the fjord also channel west and northwest winds, exponentially increasing their velocity and creating an extreme wind tunnel effect. Fog and snow squalls can come on very quickly, steeply reducing visibility. These sudden weather changes are very dangerous for navigation.

During the winter, ice on the St. Lawrence obstructs the passage of ships and creates a major obstacle to navigation. When the spring thaw comes, mounds of ice can build up and create ice jams that block the river. Large floating blocks of ice can also impede navigation.

In modern times, an efficient icebreaking program ensures safe passage for ships and reduces the impact of spring floods by allowing water to flow freely. The icebreaking program makes it possible for most Canadian ports to remain open year round. During the winter, ice conditions on the St. Lawrence are monitored 24 hours a day.

In 1873, the Government of Canada launched an icebreaking program in Canadian waters at the request of Prince Edward Island. As a condition of its entry into Confederation, the province had requested year-round ferry service. Over the first half of the 20th century, the government put together a fleet of icebreakers: the Champlain and the Montcalm in 1904, the Lady Grey in 1906, the Saurel in 1929, the N.B. McLean in 1930 and the Ernest Lapointe in 1940. Three more large icebreakers joined the fleet after World War II: the D'Iberville in 1952, the Labrador in 1953 and the John A. Macdonald in 1960.

The Lady Grey remained in service until 1955, when it sank after striking the Cité de Lévis. Despite the hard work of this fleet of icebreakers, winter navigation on the St. Lawrence did not officially take off until February 13, 1959, when a Danish cargo ship, the Helga Dan, reached the Port of Quebec City. Since the early 1960s, icebreakers have made it possible for ships to sail up to the Port of Montreal. However, the portion of the St. Lawrence upstream of Saint-Lambert, which includes a series of locks, generally remains closed from early January to late March.

Transcription

(Panoramic view of a vessel on the frozen river off Trois-Rivières. The captain discusses his career path. He is standing outside in front of the river. The ice is moving quickly, and the oil tanker Laurentia Desgagnés can be seen at anchor.) I joined the Coast Guard at age 17. I completed my studies in Nova Scotia, and I’ve been with the Canadian Coast Guard for 38 years. Now I’m an icebreaker captain, working on the St. Lawrence and in the Arctic. We go wherever the ice is. I decided to join this line of work because my uncle did the same thing in the ‘60s. He showed me Super 8 videos he had taken in the Arctic. You could see polar bears, icebergs, Inuit people, (Photo of a polar bear in the snow) all kinds of things. It really sparked my imagination. I’ve always been drawn to the sea. (Close-up of light reflecting off a glacier.) When I was a boy, Cousteau’s films moved me deeply (Close-up of a huge iceberg floating on the water.) and steered my choice of career. (Photo of several icebergs reflected in the water.) Chance played a role, but at the same time I feel there was already a path laid out for me in this line of work. When I graduated from the Coast Guard College, I was assigned to the Quebec City region. I mostly worked on the St. Lawrence and along the Seaway. I went to the Great Lakes several times. And I also visited the Arctic many times in summer. (Music. Photo of several ships sailing in a line on Lake Superior. Photo of an icebreaker on the Arctic Ocean, under a dim purplish light.)

What I love most is the Arctic. (Photo of a frozen Arctic landscape, with the sun’s rays breaking over the horizon.) Navigating on the river, pilotage, navigating in confined waters—that’s challenging and exhilarating. (The captain stands in front of the frozen river.) It takes constant focus. You need to work with the other vessels, behind you and those coming towards you. In the summer there’s all sorts of little cruise boats and pleasure craft. (Photo of the ocean with snow-covered mountains on the horizon.) But in the Arctic, it feels like you’re on an expedition. When you go up north, you’re gone for three or four months. You need to bring all your food, equipment and fuel. You need to predict what supplies you will need. Conditions are ever-changing, and the territory is vast. The ice is much more severe than what we have down here on the St. Lawrence. (Music. Photo of a mountainous, snow-covered landscape and ice floating on the ocean.)

Arctic landscapes are breathtaking. (Photo of the sun’s rays breaking through the clouds above the frozen ocean.) Very few people visit the Arctic. We get to go there fairly frequently, once a year in the summer. Once or twice. Sometimes we do two trips a year. The landscapes are fantastic. So are the plants and the animals. When you get a chance to go on land, you notice that it’s not just a uniform brown like it seems from the boat. When you get near, the tundra is full of colour in the summer. (Photo taken near Hudson’s Bay, showing choppy waters and colourful vegetation on the shore.) As for the animals, there are bears, whales, birds. (Photo of two walruses with their long tusks.) None of those animals can be found in the south. It’s really amazing! The Arctic changes you. When you visit the Arctic, it changes who you are. Every time I’m there, it really hits me. I love the peace and unspoiled beauty of the Arctic. It’s an exceptional place! (Music. Photo of a turbulent river crossing the tundra near Hudson’s Bay. Lichen and plants grow on the rocks.)

You need to be curious to enjoy this job. Otherwise, you’ll get bored out on the water with nothing around. You need to want to know what’s going on with meteorological phenomena, the ice, the vessel itself—you need to understand your vessel and how it works. So you do need to have a good academic background, (Photo of two ships and an icebreaker crossing the frozen gulf.) especially if you want to be an engineer or a navigation officer. You have to earn certificates. It’s a fairly intensive course of study. You have to take it seriously. You can tell when young people have done their work. When they join our fleet after they graduate, you can see how well they understand the theory. It’s great to see them come on, with everything they’ve learned, and get to put it all into practice. They make connections. It’s fun to see new grads transform into experienced mariners. (Music. Photo of the frozen river off Quebec City, with the two bridges on the horizon.)

The biggest challenge when it comes to navigating the St. Lawrence in winter is the ice. It’s definitely that. The ice takes many forms. There’s ice along the shorelines, where people go to fish—ice fishing in particular. There’s also moving ice. The currents can push the ice together, and pressure builds up. The weather also changes things. If the wind is coming from the north-west, we’ll get lots of snow. Wet snow on top of the ice forms a sort of thick, sticky soup that makes it hard for boats (Photo of a barge stuck in the ice on Lake Saint-Pierre.) to pass through the channel. The ice is really what causes the most trouble! (Music. View of ice and water moving in the river.)

Lake Saint-Pierre is actually just a wide part of the river. When I was young, I thought it was a true lake, because I heard people call it Lake Saint-Pierre. But then I understood that it’s just part of the St. Lawrence. It’s very shallow. It’s very wide and very shallow. There’s just one area in the centre, a channel that is maintained and clearly defined, where ships can pass. The rest of it is only accessible to pleasure craft. There are places where the water is only 4 or 5 feet deep. That’s a characteristic of the lake. And all that thick ice that builds up on either side of the channel can sometimes come loose. That’s why we have cameras on Lake Saint-Pierre, so we can watch from a distance. We also use radar when visibility is restricted. We can watch the ice move on the radar. It’s like the radar system on a ship, but it’s installed on an island in Lake Saint-Pierre. The ships that pass along the channel also report any unusual conditions they encounter. That’s how we’re able to monitor the ice-pack. Every winter, there are always a few occasions when part of the ice breaks free. (Ice on the river with the Laviolette Bridge in the background.) It’s just how it is. It’s not a crisis. It’s often caused by a thaw or an abrupt change in temperature that creates surface tension. Then the wind blows the right way and the ice cracks, and you’ve got a piece that breaks off. It happens every year. Sometimes the pieces are small. Other times, they can be very large, and we need to take quick and decisive action to break them up. (Music. Close-up of an iceberg that has broken off an ice shelf in Greenland. Aerial view showing the massive size of the iceberg. The tiny red dot at the top is an icebreaker.)

Ice can block the channel, or a piece of ice weighing million of tons can push a ship off course. Ice is heavy. It can push ships right out of the channel. Or it can simply block up the channel and stop other pieces of ice from flowing downstream, leading to an ice jam. The ice builds up all the way to the bottom. (Panoramic view of ice moving on the river.) This makes water levels rise upstream, theoretically up until Montreal. That’s the danger. Any piece of ice that starts moving could cause a jam somewhere, even right here against the pillars of the Trois-Rivières bridge. They get caught there and block everything. That’s when we need to quickly head out to break up the ice and get things moving again. (Music. Ice moving on the river.)

Spring break-up starts when the weather gets warmer. But we don’t wait for the ice to break up on its own and cause problems. We’re proactive. As soon as we know a thaw is on its way, we start breaking up the ice covering to facilitate navigation and stay one step ahead of mother nature. If we waited and left it there, some of it would still be there in May. So we speed up the process to facilitate navigation and quickly return to summer conditions. (Music. The icebreaker Martha L. Black moored at the wharf in Trois-Rivières.)

When the winter draws to an end, we make use of various tools. Since Lake Saint-Pierre is so shallow, the powerful icebreakers (The icebreaker Martha L. Black moored at the wharf in Trois-Rivières.) can’t leave the shipping channel to break up the ice. That’s why we keep hovercraft here in Trois-Rivières. They can leave the channel and break up the ice using a special technique. They break up the ice covering outside the channel. They’re also used on smaller rivers, especially the rivers on the south shore—the Châteauguay, the Yamaska, the Saint-François—in certain seasons, where they do exactly the same job, and prevent ice jams. They break up the ice at the mouth of the smaller rivers, so when spring floodwaters flow down and the ice breaks up, it has somewhere to go. It doesn’t build up at the river’s mouth while it’s still covered in thick ice. The thick winter ice is no longer there. We remove it so other ice can flow out of there normally. (Photo of an icebreaker on the frozen Saguenay River, with the fjord in the background.) (Music. Photo of ice on the Saguenay River and the majestic Saguenay Fjord.)

In the winter, when you’re on the ship, there’s something to do 24 hours a day. The ship always needs to be ready to go, and you always need to be ready for action. There are times when we’re just waiting, keeping an eye on the ships and the ice. Other times we need to take action. We usually try to take action during the day, because when it’s dark, it’s more difficult to deal with problems. It’s hard to see what’s going on around you. Sometimes we still need to take action, if the situation permits or if it’s necessary. But ideally, we prefer to work in the daylight, which gives us a fairly small window of time in the winter. On board the ship, (Photo of two cargo ships sailing through ice near Quebec City.) someone is always on duty, 24 hours a day. We work alternating shifts. Some of the crew work the day shift. So does the captain. It starts at 6 a.m. and finishes at 6 or 6:30 p.m. But we remain on call at any time. We have regular business hours (Photo of the frozen river off Quebec City with the two bridges on the horizon.) when, if we’re not taking action, we catch up on paperwork. We plan upcoming voyages and repairs, carry out personnel management. Everything you do in a regular business, we also do aboard a ship. (Music. Photo of a ship seen from afar on the frozen river at sunset, sailing towards the bridges of Quebec City.)

In the old days, you would have to plot a course on a paper map. You’d take a bearing and record your direction and speed. Fifteen minutes later, you’d take another bearing. In between, you’d be going by guesswork. You didn’t always know your exact position. Now the ship has an electronic chart and you always know exactly where you are. There’s no more guesswork, and it’s instant. Things have changed, and we’ve had to re-examine our approach. Some tasks no longer need to be done. Other new tasks have been added. We need to fully understand our navigational tools. We need to review all the processes on a regular basis to make sure we understand them, and to check if they are still necessary. Things aren’t changing at lightning speed, but over the past 10 years there has been a lot of progress. The new technology has made life much easier for mariners. It’s safer, and we have more information. Electronic maps have really changed our lives. (Music. Photo of the St. Lawrence Seaway in winter.)

Thousands of years before the first Europeans set foot in North America, First Nations people used the St. Lawrence for travel, trade and to acquire food. The Algonquins called this mighty river "Magtogoek," the path that walks.

Aboriginal people travelled in light yet tough birchbark canoes. These vessels were easily repaired using natural materials. After contact, some Europeans quickly adopted canoes as a means of transportation. They were well-suited to local conditions, as they could be portaged around rough stretches of the St. Lawrence. They were also able to move fairly quickly along the water. Canoes remained in common use until the middle of the 18th century.

Birchbark canoes had a fir or cedar frame wrapped in sheets of birchbark stitched together with spruce root. To make them waterproof, the seams and joints were sealed using spruce and pine gum mixed with tallow. These vessels were pointed at both ends to decrease water resistance. For Europeans explorers and fur traders, birchbark canoes were indispensable. They would acquire them from Aboriginal artisans.

To make a canoe, first the bark had to be removed from a white birch. Next, the bark sheet was smoothed out and placed on the ground. To define the size and shape of the canoe, a frame was placed over the bark and weighed down with large stones. The artisan would slit the bark along the sides of the canoe to form flaps, then soften those flaps by pouring hot water over them. Then, he would fold them up to form the sides, using stakes to hold them in place.

Spruce roots were harvested and processed, then the prepared roots were used to stitch sheets of birchbark together. Next, cedar or spruce wood was cut, and the pieces were boiled and shaped to build the ribbing of the vessel. The ribbing was solidly bound to the birchbark, giving the canoe its shape. It would take two people around two weeks of work to build a birchbark canoe. Various types of canoe, of different sizes, were used for a number of purposes.

Around 1000 AD, the Vikings crossed the Atlantic Ocean from Norway and sailed up the St. Lawrence in their drakkar ships. These narrow ships, 20 to 30 metres long, were propelled by large square sails and teams of oarsmen. Traces of Viking occupation are still visible today in Newfoundland. Some believe they also travelled up the gulf to the North Shore and the Gaspé Peninsula.

During his first voyage, on July 16, 1534, Jacques Cartier met with around 200 Iroquoians from Stadacona (now Quebec City) who had come to the Gaspé Peninsula on a fishing expedition. To the explorer's surprise, these Aboriginals seemed to be familiar with foreigners. In fact, they had probably already crossed paths with European fishermen. Around 1500, English, French, Spanish, Basque and Portuguese fishermen began visiting North America to fish for cod and hunt whales. Breton and Basque fishermen took their sailing ships further into the gulf and the lower estuary. Traces of ovens used to melt down whale oil are still visible on Île aux Basques, off Trois-Pistoles. During his second voyage in 1535, Jacques Cartier continued upriver to Hochelaga (now Montreal). He had to leave his ship, the Émérillon, when he entered the shallow waters of Lake Saint-Pierre and continue in rowboats. His journey was halted by the rapids at Hochelaga.

Jacques Cartier (2nd voyage in 1535)

On August 10, 1535, during his second voyage, Jacques Cartier gave the name "Baye Saint Laurens" to an inlet located near what is now Havre-Saint-Pierre. A few years later, translators mistakenly applied this name to the entire gulf. In 1613, the cartographer Samuel de Champlain gave the name "Grande Rivière de St. Laurens" (Great River of St. Lawrence) to the entire waterway, though he continued to write the name "Grande Rivière de Canada" (Great River of Canada) on his maps. Champlain first crossed the Atlantic to explore the St. Lawrence region in 1603. He travelled up the Saguenay and sailed the St. Lawrence to Hochelaga. On June 29, this eminent cartographer crossed a great widening of the St. Lawrence, which he named Lake Saint-Pierre.

Champlain crossed the Atlantic 23 times, and explored various parts of the St. Lawrence. On July 3, 1608, he founded Quebec City. The next year, he sailed up the Richelieu River. On July 14, he arrived at a large lake and named it Lake Champlain. In 1611, he managed to cross the rapids not far from Hochelaga, which were a major obstacle to navigation. He named the rapids Sault Saint-Louis in honour of a young crew member named Louis who drowned there. They are now known as the Lachine Rapids. In 1612, Champlain decided to pursue his exploration further upstream and took the Ottawa River. In 1615 he went still further up the river, reaching Lake Huron on August 1.

In 1629, when the Kirke brothers seized Quebec, Champlain went back to France. From there, he successfully regained the colony in 1632. He returned to Quebec in 1633. After the return of the colony, only canoes, fishing boats and merchant ships navigated the St. Lawrence. Starting in 1665, French military ships began to patrol the river to protect the colony from the Iroquois. On October 16, 1690, General William Phipps, commander of a fleet of 32 ships, unsuccessfully laid siege to Quebec. Starting in June 1759, more and more British ships sailed up the St. Lawrence. The inhabitants of New France prepared to defend their territory. But the 164 ships in the British fleet were carrying 24,883 soldiers in General Wolfe's army. The French army lost the battle on September 13, 1759. French ships would not return until 1855, long after the Conquest, when Captain Paul-Henri Belvèze sailed his ship La Capricieuse up the St. Lawrence.

In the late 19th and early 20th centuries, schooners were often used to transport cargo and passengers, as well as for fishing. Carpenters in the Charlevoix region were known for their skill in building these small sailboats, prized for coastal navigation. The Desgagnés, Audet, Mailloux, Lavoie and Harvey families were well-known masters of the trade.

Until the late 19th century, the St. Lawrence was the main route into the heart of North America. People, cargo and information from Europe converged along this single passageway.