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What goes in the water

Understanding pollution in the St. Lawrence River and what it reveals about our relationship to nature.

The trip through the locks heading into Montreal on the St. Lawrence River is long and languid.

Sitting on the top deck of their research ship, the scientists are reading, typing away on a laptop, napping under the emergency zodiac, the only piece of shade on this sweltering August day, and braiding a friendship bracelet attached to a Nalgene water bottle covered in stickers.

This is one of the few moments on the Lampsilis research vessel where time stands still, offering respite amid the usual mad dash of collecting samples and data analysis. In less than 24 hours, these scientists will be hovering over the place where the river carries Montreal’s wastewater downstream.

But for now, it’s one of the few places on the St. Lawrence River where the water is almost still.

And it’s making Elizabeth Grater — the 26-year-old in charge of a mission to survey the river’s water quality from Lake Ontario all the way to the gulf — think about place.

“Just a little while ago, there were so many trees. It was just birds,” Grater said. A wall of concrete had just replaced this part of the shore.

The ship has slowed to the spot where the shoreline of unruly bright green trees ends at the Beauharnois Canal, the first locks heading into Montreal on the St. Lawrence Seaway. The system of canals bypasses rapids in the river, and 200 million tonnes of cargo travel through it every year.

“When you’re seeing that change, it’s hard not to think, is this how we want to live? Is this how we want our cities to be structured? Is this what we want our connection to the river to be like?”

The Port of Montreal lines much of the city's shore. (Stephany Hildebrand)

The seaway represents one of the most massive industrial transformations of land in North America, and has become emblematic of the way settler societies have treated rivers as highways and dumping grounds, because they saw the water as always going somewhere bigger, further — elsewhere.

The impact of those transformations is what Grater and her team of scientists are trying to understand. Their journey on the Lampsilis over roughly 300 kilometres of river, from Cornwall to Quebec City, includes 97 stops to collect water samples along the way. (A second group embarked in Quebec City to study invertebrates for 300 more kilometres, all the way to Cacouna, where the river widens into a gulf leading to the Atlantic Ocean.)

They want to know what changes inside the water as it travels past cities, farms, islands, ports, factories. And what happens with all the wastewater Montreal pours into it, at a rate of between 2.5 and 7.5 million cubic metres — roughly the volume of the Olympic Stadium — per day.

“Understanding the way the river moves through the environment, that can give us an idea of what it’s naturally capable of doing. Like, what can it filter, what can it process?” said Grater. “And then, how are the urban spaces impacting that natural process?”

In essence, “How are humans impacting the river?”

images expandThe bulk of Montreal's wastewater, which only receives a primary treatment, comes out of a pipe on a tiny island east of the city.

The multi-year study has taken on a renewed sense of urgency as rising temperatures, more frequent heat waves and greater awareness of natural landscapes in urban areas foster a desire in Montrealers and Quebecers to rediscover the St. Lawrence.

“People want to go swimming [again],” said François Guillemette, a professor in the department of environmental science at the Université du Québec à Trois-Rivières (UQTR). “But in many places, you just can’t.”

Where the wastewater surfaces

The next day, the Lampsilis stops at a tiny, nondescript island east of the city called l’Île-aux-Vaches, where the bulk of Montreal’s wastewater effluent flows out of an underground pipe.

Grater and Guillemette are standing on the top deck of the boat, peering out at large brown circles of wastewater that have formed on the river’s surface. Guillemette holds his jacket over his nose.

Just a couple hundred metres downstream from the underwater pipe, docks and small cottages line the shore of the larger Île-Sainte-Thérèse.

“It’s always shocking to come here and see that,” said Grater, adding that the level of E.coli at which people are encouraged to avoid boating and fishing is 1,000 colony-forming units per 100 millilitres.

“Here, we’re at around 10 million colony-forming units of E.coli. So that’s a lot of E.coli,” she said. “There’s also everything associated with E.coli: heavy metals, viruses, pathogens — a lot of contaminants.”

A curious group of young scientists and crew members join Guillemette and Grater on the deck. The smell of sewer had made its way to their lab below.

They point out visible plumes of the brown liquid mixing with the river’s greenish water.

“See that? See where it’s bubbling? Ick!” Grater said.

The area is one of many on the river that, to these scientists, is symbolic of how much of what happened to the St. Lawrence is in defiance of nature. They hope understanding the river, its biodiversity and the extent of the pollution could help reverse the damage.

Each scientist on the Lampsilis has a separate research focus, but most are studying parts of the water you can’t actually see. Once the results are compiled later this year, they hope to gain a broader understanding of the health of the St. Lawrence as a whole.

Grater says she wants to help change the way communities along the St. Lawrence view the river — as not just a waterway to avoid but something to advocate for. She and Guillemette are doing so by collaborating with artists, urban planners, community groups and environmental organizations.

“So much of science is so disconnected from the community,” Grater said in July at an event in Trois-Rivières, where passersby were invited to tour the ship, learn about the microbiology of the water and participate in art workshops. “I’m trying to rethink how we use the research vessel.”

The scientists take their samples on the back deck of the Lampsilis. The pictured apparatus is called a Go-Flo and allows them to take water from specific depths. (Stephany Hildebrand)

From river bank to cement wall

The St. Lawrence is so big, so breathtakingly wide in some places, that in French it is a whole other category of river: a fleuve. It runs nearly 1,200 kilometres, more than double that if you include the Great Lakes, and drains 25 per cent of the world’s freshwater reserves, collecting the water of dozens of rivers along its course.

Four million people derive their drinking water from it.

The St. Lawrence distinguishes itself from other large rivers around the world by the fact that it begins at a lake and carries several different water masses at once.

If you were to look at it from above, you would see almost a rainbow of different shades of water flowing next to each other ranging from an almost tropical blue to lime and navy and umber made up of the dozens of tributaries flowing into its midst.

The ship Grater and the crew are using to study the river was built in 2004 and designed by scientists at Université du Québec à Trois-Rivières (UQTR). The Lampsilis is modelled on a catamaran, with two aluminum hulls that sit barely a metre below the water to navigate the St. Lawrence’s shallow waters.

After meeting Grater at Florida State University, Guillemette recruited her in 2017 to help revive the Lampsilis and make the research conducted on the vessel more collaborative.

Before that, the ship had been sitting idle in a warehouse for four years due to a lack of funding.

Guillemette says the research conducted on the Lampsilis in the past, as on similar vessels, was done in silos. Scientists would present a specific research question — say, about a contaminant in fish — they’d go on a trip with the boat to collect samples, type up a study, “and that’s it,” he said.

This year, the boat entered yet a new era as Guillemette handed command and planning over to Grater, who recently completed her master’s, as chef de mission. The five other scientists on board until Quebec City were undergraduate and graduate students.

Guillemette says he encourages students to join these missions as a way of absorbing the environment they’re studying. “You can read about a system all you want, but you will never understand it until you see it,” he said.

The ship itself embodies how the river has changed. Its name has two meanings. For one, it refers to a species of freshwater mussels, lampsilis, whose population in the St. Lawrence and other Canadian rivers, was decimated due to competing for food with the invasive zebra mussels.

The species has since bounced back and was upgraded from endangered to a “species of special concern” by the federal government.

It’s also the name of a lake that existed 10,000 years ago, around the time the St. Lawrence River was formed, when the ice covering North America melted away.

The Lampsilis docked in Trois-Rivières.
François Guillemette helped revive the Lampsilis after it spent years in a warehouse.

Built in 1954 in partnership with the United States, the seaway was a boon for Montreal, whose river banks became locks and piers for the exchange of goods from thousands of huge vessels every year.

But its creation caused widespread destruction, flooding 10 Ontario towns, effectively wiping them from the map and displacing 6,500 people. A devastating 1,262 acres of land was expropriated from Kahnawake, the Kanien’kehá:ka community of 8,000 people south of Montreal, removing its access to the river and a way of life.

A project is underway in Kahnawake to restore the bay, which has become so thick with weeds it’s almost impossible to paddle. Morgan Kahentonni Philips, an Indigenous scholar specializing in resiliency who grew up in Kahnawake, says the project is part of the community’s push to reclaim the river.

“Kahnwake means ‘by the rapids,’” she said. Elders in the community “played on the river, they washed their clothes on the river, they fished in the river.”

“It’s a devastating loss,” she said. “For Indigenous people, resilience is the fact that we’re still here.”

100-km plume of wastewater

The industrial transformation of the river continues to distance people from nature. Unlike other waterfront cities, there’s almost no access to the river in downtown Montreal. Lego-like stacks of shipping containers stand tall where beaches or trees may have been. In many places, you’d never guess there was a river so close by.

Finding a safe place to swim over the 50 kilometres of Montreal’s island is a feat. The city operates two small beaches at either end of its territory, but has to close them several times every season due to high levels of fecal coliforms.

The effluent is a combination of wastewater coming from homes, industry, storm runoff and snow melt. It receives a primary treatment at the treatment plant on the island’s east end. Solids and some nutrients are filtered out, but a lot of other bad stuff is still in the water once it makes its way to the river, including E.coli, pharmaceuticals, heavy metals, diseases and other pollutants associated with humans and cities.

When it rains and the amount of wastewater exceeds what the treatment centre can handle, the excess that hasn’t been filtered winds up in the river.

A major upgrade that will incorporate ozonation in the treatment centre — among the largest in North America — has been delayed by more than 10 years, and costs have nearly tripled. Once in place, it’s expected to eliminate 99 per cent of pollutants.

Government officials have defended how much wastewater Montreal and nearby cities pour into the river, arguing it’s sufficiently diluted. But traces of it have been found as far as Trois-Rivières, 100 kilometres away.

Urban designer Shin Koseki joined the Lampsilis for part of its journey.
A sample from the wastewater discharge site, right, compared with one taken elsewhere in the river. A much smaller portion of water was used for the sample to the right.
Maria Pelusi and Kelsey Cullen collect a water sample for their research.
Downtime is rare but prized on the boat.
images expand

Agricultural runoff, also full of E.coli and nutrients, is another unnatural source of materials finding its way into the river through its tributaries, such as the Richelieu and Yamaska rivers.

Studies have shown the effect of the wastewater on fish, which includes disrupting their reproductive systems. But little is known about how it impacts the food web and bacterial communities, which in turn can influence the amount of carbon dioxide the river releases into the air.

Water bodies

Around Montreal, the boat nearly snakes its way along through the many sites the scientists have chosen to sample. Every one of them is divided by three stops along the river’s width.

Reporters, photographers, artists, urban planners and environmentalists have been invited onboard in different places and the scientists and crew judggle answering their questions while collecting, and processing samples.

In the boat’s small lab, the researchers boogie to Fouki and sway to Beyoncé, Harry Belafonte, Rihanna, Jack Johnson.

“I was nervous that everyone was going to be uptight or, like, getting under each other’s feet,” said Kelsey Cullen, a graduate student at Clarkson University in Potsdam, N.Y., who is charting the river’s microorganisms. “But we’ve all gotten into this groove. It’s like a dance. We dance around each other in the lab and we’re just constantly joking and playing pranks on each other.”

Quieter moments offer space to observe the changing landscape. Sometimes the samples themselves reflect those changes. The water around Montreal, and especially near the wastewater discharge, takes longer to filter and even causes instruments to back up and spurt E.coli-filled water every now and then.

One of the boat’s guests is Shin Koseki, an urban designer and professor at Université de Montréal. He is exploring ways to improve water access for people who may face social, economic and literal barriers to the St. Lawrence, such as living near port lands instead of waterfront parks or beaches.

“We think of these rivers as places that are locally important, but actually we have to consider them as global weather regulators and global economic and ecological regulators,” Koseki said.

Another is Matthew Chapman, an environmentalist who purchased a small island with his wife in a contaminated part of the river east of Montreal, hoping to turn it into an “eco-retreat.”

“It’s work to invite other experts or artists to enter your research space. You have to be open to that kind of potential chaos — but also potential enlightenment,” said Elizabeth Miller, a professor at Concordia University, who visited the boat in 2019 with colleague and artist Kathleen Vaughan. Vaughan is working on a multi-year art project involving the river and Miller recently created an app with students mapping waste-related sites around Montreal and its shoreline, called “WasteScapes.”

“I can completely understand why a scientist would not want to open up a very, very rigorous procedure. But they’re also opening up the minds of future generations.”

A storm looms over the river as the Lampsilis research vessel makes its way to Quebec City. (Stephany Hildebrand)

One stop offers a nearly perfect view of the place where the Ottawa River, the St. Lawrence’s greatest tributary, meets the glassy blue-green water of Lake Ontario east of Montreal.

The Ottawa River is dark and brown, infused with the rich earth and vegetation of the Ottawa Valley, like tea. Grater calls it “the Coca-Cola.” The water from Lake Ontario is clear, fast and low in nutrients; the Ottawa runs slow and steady, sticking mostly to the shoreline.

Grater rubs her hands together to create an image of the two bodies of water, which travel next to each for nearly the rest of the river’s length. Trapped between the two, she explains, is the effluent of Montreal wastewater.

Maria Pelusi, who just completed her undergraduate degree in environmental science at Clarkson University in Potsdam, N.Y., said seeing the colours of the water masses and smelling the effluent of wastewater stunned her. She gathered data about contaminants in the water with Cullen.

“I’ve swum in the river my whole life, and I eat fish from the river,” said Pelusi, whose childhood home in Ogdensburg, N.Y., is a block away from the St. Lawrence. “Part of me is a little scared of what I’m going to find.”

Pelusi gathered data about contaminants in the water and their sources with fellow Clarkson undergrad student Kelsey Cullen.

“Bacteria run the world, honestly,” Pelusi said.

How do you measure a river's health?

The aluminum factory near Sorel-Tracy, where a system of islands helps filter out pollution in the river coming from Montreal. (Stephany Hildebrand)

Scientists are hesitant to make blanket statements about the health of the river, or to appear pessimistic in any way, because of how much things have improved since the 1950s.

“We can’t be alarmist,” said Patrice Couture, a toxicologist at the Institut national de la recherche scientifique, a research institute in Quebec City, and the head of an ecotoxicology research centre called EcotoQ.

Back in the 1950s, “there wasn’t a conscience about what we were putting into the river. It really was a free-for-all. We’ve come a long way, but we’re still behind compared to other places,” Couture said. He noted European cities with rivers are more proactive in protecting the water and have better treatment plants.

Couture worries being alarmist could discourage progress, but admits Quebec’s protection measures often come after pollutants have already caused damage.

The latest assessments from the St. Lawrence Action Plan, an initiative of the federal and provincial governments, show oxygen levels in the estuary are at a record low and acidity at a record high, rising 60 per cent since 1979.

“The acidification of the St. Lawrence has been linked with the build-up of CO2 in the atmosphere,” the Action Plan says on its website.

Water temperatures are steadily increasing as well, disrupting the lives and habitats of several species.

Captain Renaud Lavoie, centre, is joined in his cabin by André Benoît Cotton, left, and Baptiste Lauzier, right.
André Benoît Cotton has worked on the Lampsilis nearly every year it was in service, most of the time as its captain.
UQTR masters student Silvia Rodriguez is measuring the water for bacterial diversity.
images expand

In 2012, scientists working for the Action Plan watched in horror as starving northern gannet chicks were abandoned at the nest on Bonaventure Island, one of the bird’s largest colonies in the province, because of warmer temperatures.

“With global warming, prey is sometimes less available to gannets when ocean surface temperatures become too warm, as was the case in August 2012,” explains an Action Plan monitoring sheet for the species.

Considered an indicator of the health of the St. Lawrence, the species’ reproductive rate still hasn’t quite recovered.

On the last day before hitting the estuary, where the St. Lawrence’s freshwater slowly begins to mix with the Atlantic seawater, the Lampsilis stops for the night in Sorel-Tracy.

Sorel, as it’s known, is an industrial town that recent housing developments are turning into a suburb of Montreal. A black cloud envelopes an aluminum factory outside the city.

What is it like to travel the St. Lawrence River on a research vessel for two weeks?

Before the river’s mouth opens to a fluvial lake about 15 kilometres wide called Lac St-Pierre, it is choked by a system of islands that act as a natural filter, sifting out much of the Montreal effluent.

“This river has an incredible resiliency,” said Jeff Ridal, the executive director of the River Institute, in an interview earlier this year. “But it’s still on an edge and we can push it over the edge if we don’t take the measures that we need to to look after this river.”

Ridal said invasive species have “altered the system so incredibly that it is never going to be, unfortunately, the river that it once was.”

When Gilbert Cabana, one of the Lampsilis’s founding scientists, is asked about the state of the river, he’ll tell people about the ship’s name, how it embodies the shifting of landscapes and the ebb and flow of species.

He says that, considering the river formed 10,000 years ago after the huge lake that took its place, the last 100 years are like 15 minutes in a day of its life.

“It reminds us of the temporal perspective — and it’s a bit humbling, right?” he said.

Grater’s thinking takes place in a closer future. She says she oscillates between pessimism and optimism about the state of the river and of the planet as a whole.

“We’re not improving the wastewater management at the rate that the cities are growing,” Grater said. “If we don’t make sure now to protect the river, then I don’t know what’s going to happen. Twenty, 30 years in the future, is it going to be so polluted that we don’t even want to go boating on it?”

To her, it’s worth every try.

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