The Doug Ford government says its vision for its second term is to get desperately needed homes built in Ontario. In York Region, the key to that vision is a massive pipeline that transfers water from one Great Lake region to another. 

Locally, it’s nicknamed the “big pipe,” even though it’s more like a grid of pipes. Mary Muter, chair of the Georgian Bay Great Lakes Foundation, said when the tunnel that hosts the system was being built almost 50 years ago, “You could walk through it.”

The big grid of pipes moves water and sewage in an intricate back-and-forth system between Lake Ontario and York Region, a suburb of 1.17 million people between Toronto and Lake Simcoe. York gets its water for drinking, and flushing toilets, from both Lake Simcoe and Lake Ontario. About 80 per cent of the wastewater produced by York Region travels over 60 kilometres downstream to be cleaned at one of North America’s best sewage treatment facilities, the Duffin Creek Water Pollution Control Plant in neighbouring Durham Region, population 700,000. 

Wastewater infrastructure is essential to development, and so essential to Ontario’s plans. As the Ford government seeks to rapidly usher in new construction in York, it has its eyes on the big pipe, which it plans to upgrade and run through the protected Oak Ridges Moraine to the Duffin Creek facility. The treatment plant is also set to be expanded so that it can handle 10 to 12 per cent more of York Region’s waste. By 2051, Ontario plans to move much more water — tens of millions of litres — out of the Lake Huron watershed every day.

Already, some of the water taken from Lake Simcoe and Georgian Bay is returned after treatment at Duffin Creek. But most is released into Lake Ontario, and that won’t change: Ontario’s new proposal would permanently increase the quantity of the water moving between these two watersheds to an amount not yet specified. It’s a move that could irreversibly alter the composition of two Great Lake ecosystems, and affect York Region’s access to clean drinking water.

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The Narwhal’s Ontario bureau is telling stories you won’t find anywhere else. Keep up with the latest scoops by signing up for a weekly dose of our independent journalism.

“The cumulative impacts of this proposal could be larger than we think,” Andrea Kirkwood, a professor of biological sciences at Ontario Tech University in Oshawa, told The Narwhal. “We should all be concerned that the Ontario government is messing with our water.” Lake Ontario is already dealing with unprecedented levels of accidental sewage spills: 396 million litres of wastewater have flowed into the lake since 1996, resulting in a recent provincial decision to audit parts of the lake sewage system.

Ontario’s proposal to shift more of York Region’s sewage to Lake Ontario was approved last October — the same day Ford’s Progressive Conservatives released controversial Bill 23, the More Homes Built Faster Act, which proposes to weaken or eliminate a long series of environmental regulations to facilitate development, particularly of single-family homes. If the plan goes through, it will end a heated 14-year-long debate over how to handle wastewater in York, a region that is set to nearly double in population by 2051, and finally kill a proposal to build a new facility to treat sewage locally. 

Aside from environmental concerns, there are diplomatic ones: Kirkwood and four other Great Lakes experts say that by rapidly ushering through this decision, Ontario may be breaching an international agreement it signed in 2005, pledging to protect and improve the Great Lakes ecosystems in perpetuity. 

The agreement, called the Great Lakes-St. Lawrence River Sustainable Water Resources Agreement, was signed by all the American states and Canadian provinces surrounding the Great Lakes, including Illinois, Indiana, Michigan, Minnesota, New York, Ohio, Pennsylvania, Wisconsin, Québec, and Ontario, led then by Liberal Premier Dalton McGuinty. The goal, according to the agreement, was to ensure “precaution, ecosystem protection, and recognition of cumulative impacts and climate change uncertainties” when managing the Great Lakes, the largest freshwater system in the world. Together, the five lakes hold around 20 per cent of the world’s surface freshwater, and about 85 per cent of North America’s.

Each state and province was required to adopt the agreement’s minimum standards and embed the idea of regional consultation into its own laws; Ontario’s regulations came into force in March 2015. Each state and province also had to develop and implement a water conservation and efficiency program. 

Map of the Great Lakes and surrounding states and provinces
Signed in 2005, the Great Lakes-St. Lawrence River Sustainable Water Resources Agreement is a historic agreement designed to ensure greater regional collaboration and cooperation in the protection and management of Great Lakes ecosystems. Map: Shawn Parkinson / The Narwhal

The agreement explicitly bans any new, large “intra-basin transfers,” or the building of pipelines, canals or other man-made channels to move large quantities of water from one watershed to another, unless all signatories are properly informed and make an exception to allow it — which has only happened once. 

Intra-basin transfers can have major long-term environmental impacts on watersheds — all the land that drains into a lake, river or stream  — by contributing to fluctuating water levels, which can damage wetlands and surrounding ecosystems, and increase contamination of the water itself. 

In theory, the cross-border Great Lakes agreement is meant to ensure that “water stays within its boundaries,” Kirkwood said. Each Great Lakes basin acts as a bathtub, she explains, with water draining naturally from the lake into the ground and through the waterways and rivers, and then used for irrigation, drinking and other purposes. As development and urbanization around the Great Lakes increases, more pollutants (“more poop, more car pollution, more road salt, more agricultural waste”) enter the water and disrupt the natural hydrological process.

The agreement limits large intra-basin transfers to try and keep development in the Great Lakes region somewhat sustainable. “The idea is that if you’re planning development that your own watershed can’t contain, you shouldn’t develop,” Kirkwood said. “The agreement ensures we don’t overdevelop.”  

But reality and politics are more complicated. By planning to send more of York Region’s sewage to neighbouring Durham Region, the Ontario government is “breaking the spirit of the agreement” and permitting more development than the watershed can handle, Kirkwood said. For humans around Lake Simcoe, this decision could mean less or dirtier drinking water. For other animals, an entire ecosystem will be disrupted. 

Lake Ontario in the winter
Lake Ontario provides water to communities across the province and on both sides of the U.S.-Canada border. It is already dealing with unprecedented levels of accidental sewage spills: 396 million litres of wastewater have flowed into the lake since 1996. Photo: Timothy Neesam / Flickr

‘A series of promises’: is Ontario setting a bad precedent for development around the Great Lakes?

Per the agreement, Ontario has to seek permission to do any intra-basin transfer and justify that “you have done everything you can to conserve water and there is no other way,” said Gail Krantzberg, an engineering and public policy professor at McMaster University. 

Krantzberg served the McGuinty government as a senior policy advisor on the Great Lakes during the 2005 negotiations of the agreement, and said Ontario “fought really hard for the lowest possible threshold so water systems weren’t disrupted.” The proposal for any diversion, major or minor, was meant to be scrutinized since changing water processes can forever change a watershed. 

All signatories are members of a group called the Great Lakes St. Lawrence Governors & Premiers, which upholds the agreement and brings all jurisdictions together twice a year. In an interview with The Narwhal, the group’s deputy director, Peter Johnson, said there are no legal ramifications or financial consequences for a signatory who breaches the agreement. There may, however, be judicial investigations and dispute resolutions. 

“This is a good faith agreement between the governors and premiers,” Johnson said from Chicago. “It’s a series of promises.” 

The 2005 signing of the Great Lakes-St. Lawrence agreement
In December 2005, former Ontario Liberal Premier Dalton McGuinty (bottom right), then-Quebec environment minister Tom Mulcair (top right) and eight U.S. governors signed the Great Lakes-St. Lawrence River Sustainable Water Resources Agreement. Photo: Great Lakes St. Lawrence Governors & Premiers

Ontario did briefly mention York Region’s expanded wastewater plans at the last meeting of all the signatories in December, according to speaking notes Johnson shared with The Narwhal. Those show that Jennifer Keyes, a senior policy director with the Ministry of Natural Resources and Forestry, shared 11 updates with the group — the very last one about the planned increased flow of treated wastewater to be discharged into Lake Ontario. Few details were provided about the impact. Keyes committed to meet the intra-basin transfer conditions. 

Others have asked the signatories to press for more detail. A group of three environmental organizations watching over Georgian Bay on Lake Huron has written to all the Great Lakes and St. Lawrence governors and premiers with a request to “urgently review” Ontario’s apparent breaches of the agreement. 

Muter, who is one of the authors of the letter, told The Narwhal she’s worried about the precedent this decision may set for all the other signatories, as they also look to bolster development and agricultural activity to house and feed growing populations. 

“Once you allow such large diversions of water, how are you going to say no to subsequent requests?” Muter told The Narwhal. “Will all the Great Lakes be drained or destroyed to build these houses?”

‘The idea is that if you’re planning development that your own watershed can’t contain, you shouldn’t develop.’

Andrea Kirkwood, professor of biological sciences, Ontario Tech University

Robert Dodd, a spokesperson for Ontario Environment Minister David Piccini, did not respond to detailed questions from The Narwhal about the status and impacts of this project. In an email, Dodd stated that York Region “is expected to play an important role in fulfilling Ontario’s housing needs.” 

“We will continue to meet our intra-basin transfer agreement obligations, and any other assertion is false,” Dodd wrote. Dodd added that Ontario hasn’t violated the agreement, and continues to return some water to Lake Simcoe and Georgian Bay after treatment at the Duffin Creek facility, although he did not specify how much. 

“Wastewater from York can continue to be serviced by the Duffin Creek Water Pollution Control Plant and there will be no impacts to the water quality of Lake Ontario,” Dodd said.

A sunset on small, shallow and sensitive Lake Simcoe
Municipalities, environmentalists and First Nations were concerned about a long-controversial proposal to build a new sewage treatment facility on Lake Simcoe, which is small, shallow and sensitive. This decision is the end of that idea. Photo: Shutterstock

But concerns remain. While Ontario does already transfer water between the Lake Ontario and Lake Huron watersheds, that process was in place before the Great Lakes agreement took effect in the province in 2015. The new proposal is much larger: estimates from the province and York Region suggest up to 20 to 40 million litres more could be transferred from Lake Simcoe and Georgian Bay to Lake Ontario every day by 2051. Even if some of this water is returned, the environmental impact of this increased transfer of water could be devastating to the health of Lake Huron’s Georgian Bay, which already has consistently low water levels, and Lake Ontario, which is already suffering the impacts of sewage waste. 

In 2021, Ontario and Canada signed a new agreement to preserve the Great Lakes ecosystem as part of the federal government’s Freshwater Action Plan, which has allocated $44.84 million to the protection of the Great Lakes. The agreement is touted in the Ford government’s “made-in-Ontario” climate plan and promises to “protect Great Lakes water quality from threats such as harmful pollutants, algal blooms, invasive species and the effects of climate change.”

While there is no obligation for the province to directly inform the federal government of its plans, the action plan promises collaboration to ensure greater monitoring of the health of the lakes. There’s particular focus on reducing the amount of phosphorus, a mineral present in sewage that can cause excess algae to grow in water, dumped in the lakes.

In an email, Kaitlin Power, a spokesperson for Environment Minister Steven Guilbeault, said his office is “closely monitoring developments to ensure that potential impacts on the Great Lakes water quality and quantity are properly understood.” Federal scientists aren’t worried right now, and have not heard any concerns from the U.S. Great Lakes states, Power said, adding that if phosphorus levels increase as a result of the wastewater proposal, Ontario would no longer be in compliance with the agreement it signed on to. 

A duck on Lake Ontario
Transferring large amounts of water from one Great Lakes basin to another could disrupt the natural hydrological process that wildlife, plants and humans depend on. Photo: Carlos Osorio / The Narwhal

“Agreements are in place to ensure that we all adhere to the principles of precaution,” Jérôme Marty, executive director of the International Association for Great Lakes Research, told The Narwhal. “Increasing population and urban and agricultural development are the greatest threats to the Great Lakes. Yes, we can build all these houses tomorrow but in the long-term we won’t have enough drinking water. Do we want that?”

“The Great Lakes are big but they are not infinite,” Marty added. “We are fortunate to have access to an extremely valuable natural resource. And the Ontario government is proposing an illegal project that will destroy them.” 

‘Some tools to fight agreement’: can leaders keep Ontario in check?

The proposal to transfer wastewater from Lake Simcoe to Lake Ontario was released after a government-appointed advisory panel concluded that it would be “the most effective option available” to deal with increased sewage in York, both in terms of financial costs and environmental sustainability. The long-debated idea to build an entirely new facility would double greenhouse gas emissions and phosphorus in small, shallow and sensitive Lake Simcoe, the panel found.

The Chippewas of Georgina Island — whose 923 residents live in Lake Simcoe, source their drinking water and food largely from the lake and have been on a boil water advisory since 2017 — have long opposed the construction of a new sewage facility. Ontario’s decision was “bittersweet,” Brandon Stiles, the nation’s environmental coordinator, told The Narwhal. 

“We’re relieved it’s not going to directly impact Georgina Island … but now it’s just a different part of our backyard,” Stiles said. “We’re very concerned about the way decisions are being made. It bypasses our duty to consult and overlooks our constitutional rights.” Stiles said the nation will not support any sewage solution without a new environmental assessment that considers the impact to First Nations of Ontario’s decision.

Map showing location of Duffin Creek Water Pollution Control Plant as well as York, Durham, and Toronto.
Estimates from the province and York Region suggest up to 20 to 40 million litres more wastewater could be transferred from Lake Simcoe and Georgian Bay to be treated at the Duffin Creek facility then released into Lake Ontario every day by 2051.  Map: Shawn Parkinson / The Narwhal

Despite growing concerns, Environment Minister Piccini accepted the panel’s recommendation. In an interview with Durham Radio News two days after the decision was released in October, he said the Duffin Creek facility was operating “at less than 60 per cent capacity” and that there was “lots of room to support growth.”

“And this isn’t growth happening tomorrow: this is growth happening outwards to the year 2051 and beyond,” he added. “Lake Ontario is a large receptor body, relative to other smaller bodies of water, and is more than capable of handling this.”

Kirkwood said she agrees with Piccini that the plant is operating below its full capacity. The more significant problem she sees is increased pollution in Lake Ontario. The Ontario government seems to be betting that the lake’s vast size and volume will allow it to sustain increased wastewater, but Kirkwoood believes this gamble may backfire.

“This is the last lake that receives everything, and we’re not thinking about its future,” she said. 

“The algae in Lake Ontario has already created a shag carpet along the shoreline. If the solution to pollution is dilution, Ontario is doing the complete opposite of that.”

The shore of Lake Ontario, carpeted with algae, which can be caused by phosphorus from sewage.
Wastewater contains phosporous, a mineral that can cause excess algae to grow in water, reducing oxygen levels for aquatic life. Lake Ontario is already dealing with excess levels of algae growth. Photo: Shutterstock

Even the government-appointed panel advised great caution in recommending this move, repeating at four different points in its report that a review of the Great Lakes-St. Lawrence River Sustainable Water Resources Agreement “should be conducted” to determine if the change in intra-basin transfer meets its requirements. The panel says the increased intra-basin transfer wouldn’t occur “until approximately 2039 to 2041” giving the signatories of the agreement “ample time” to consider an amendment to the transfer limit “if that is required.” The panel notes that the wastewater sees its “final discharge to Lake Ontario,” not mentioning how much will be returned to Lake Simcoe.

To date, the Great Lakes-St. Lawrence governors and premiers have only approved one intra-basin transfer. In 2008, the city of Waukesha, Wis., west of Lake Michigan, wanted drinking water from the Great Lakes, as its diminishing groundwater supply was contaminated with naturally-occurring radium, a carcinogen. Its application for an intra-basin transfer was approved after six years of heated deliberations with the condition that Waukesha’s wastewater (some 8.2 million gallons, or 31 billion litres, per day) was appropriately treated and then returned to the Great Lakes basin.

‘The agreement doesn’t give them a total green light to do whatever they want. And it’s not going to prohibit them either. But it gives folks some tools to fight development, mainly regulatory requirements.’

Noah Hall, professor of environmental law, Wayne State University

In approving Waukesha’s application, the governors and premiers made a significant amendment to the agreement: giving themselves more oversight powers, so that any permission for an intra-basin transfer can be revoked if the water isn’t properly treated and returned.

Noah Hall, an environmental law professor at Wayne State University in Detroit who helped draft the 2005 agreement, told The Narwhal suburban sprawl was central to negotiations. Every jurisdiction wanted more access to the Great Lakes to facilitate development, with Ontario talking about York Region’s wastewater problems even then.

“It was probably the single, biggest, toughest issue,” he said. “There was essentially unanimity that, while they didn’t want diversions out of the Great Lakes, all the jurisdiction wanted to leave some room for Ontario, Wisconsin or Ohio to do some version of this.”

Returning water to Lake Simcoe after its been treated at the Duffin Creek wastewater facility would be expensive. But 'not doing so could be even more costly and damaging.'
Returning water to Lake Simcoe after its been treated at the Duffin Creek wastewater facility would be expensive. But ‘not doing so could be even more costly and damaging.’ Photo: Shutterstock

To ensure minimal environmental damage, Hall said the agreement mandates regional reviews of the points where water is taken out and then discharged. “It’s not a sword, it’s a pen,” Hall said. “Everyone around the Great Lakes should have full knowledge of the risks and potential harms and the desire behind the project.” 

“The agreement doesn’t give them a total green light to do whatever they want. And it’s not going to prohibit them either,” Hall said. “But it gives folks some tools to fight development, mainly regulatory requirements.”

Transferring wastewater between lakes would be “very expensive,” Krantzberg said. Putting water back in Lake Simcoe after it’s been treated at Duffin Creek would be even more expensive. But “not doing so could be even more costly and damaging,” she said.

And besides, it’s the agreement Ontario is bound to. Krantzberg said it is up to the governors and the premier of Quebec to “force” Ontario into releasing more details about its plan. What she really wants is the Ford government to “consider returning water to Lake Simcoe and Georgian Bay, where it will be taken from.”

Updated on January 31, 2023 at 11:10 a.m.: This story was updated to clarify that the Great Lakes-St. Lawrence River Sustainable Water Resources Agreement is not a “treaty,” as it’s between state and provincial governments, not national governments. The update also clarifies that the agreement bans new intra-basin transfers, meaning that the amount of water that Ontario was already transferring between Lake Ontario and Lake Huron before the agreement was enforced in the province in 2015 was not subject to the agreement’s provisions.

Like a kid in a candy store
When those boxes of heavily redacted documents start to pile in, reporters at The Narwhal waste no time in looking for kernels of news that matter the most. Just ask our Prairies reporter Drew Anderson, who gleefully scanned through freedom of information files like a kid in a candy store, leading to pretty damning revelations in Alberta. Long story short: the government wasn’t being forthright when it claimed its pause on new renewable energy projects wasn’t political. Just like that, our small team was again leading the charge on a pretty big story

In an oil-rich province like Alberta, that kind of reporting is crucial. But look at our investigative work on TC Energy’s Coastal GasLink pipeline to the west, or our Greenbelt reporting out in Ontario. They all highlight one thing: those with power over our shared natural world don’t want you to know how — or why — they call the shots. And we try to disrupt that.

Our journalism is powered by people just like you. We never take corporate ad dollars, or put this public-interest information behind a paywall. Will you join the pod of Narwhals that make a difference by helping us uncover some of the most important stories of our time?
Like a kid in a candy store
When those boxes of heavily redacted documents start to pile in, reporters at The Narwhal waste no time in looking for kernels of news that matter the most. Just ask our Prairies reporter Drew Anderson, who gleefully scanned through freedom of information files like a kid in a candy store, leading to pretty damning revelations in Alberta. Long story short: the government wasn’t being forthright when it claimed its pause on new renewable energy projects wasn’t political. Just like that, our small team was again leading the charge on a pretty big story

In an oil-rich province like Alberta, that kind of reporting is crucial. But look at our investigative work on TC Energy’s Coastal GasLink pipeline to the west, or our Greenbelt reporting out in Ontario. They all highlight one thing: those with power over our shared natural world don’t want you to know how — or why — they call the shots. And we try to disrupt that.

Our journalism is powered by people just like you. We never take corporate ad dollars, or put this public-interest information behind a paywall. Will you join the pod of Narwhals that make a difference by helping us uncover some of the most important stories of our time?

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