Supreme Court ruling on Impact Assessment Act still allows Ottawa oversight of Highway 413
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Supreme Court ruling on Impact Assessment Act still allows Ottawa oversight of Highway 413

The Supreme Court of Canada ruled two weeks ago that the Impact Assessment Act, part of the federal environmental oversight regime, needs revisions to address elements that are unconstitutional. 

The decision came after the regulatory tool was challenged by the Alberta government, backed by other conservative provincial regimes, at the nation’s highest court. 

The decision, which was celebrated by some provincial leaders, defends provincial autonomy over certain decisions within their own jurisdiction. It does not, however, give Ontario Premier Doug Ford free rein to pave over large swaths of protected greenspace to build a sprawling 400-series freeway, a project that a large majority of Ontarians have been fighting since it was rebirthed with the election of the PCs in 2018.

The Highway 413 project Ford and his PCs put back on the table, after it was cancelled by the previous Liberal government for failing to offer any benefits, still has to adhere to a wide range of federal legislation aimed at protecting habitat, species at risk, fish populations, sensitive ecosystems and ensuring proper consultation with all groups, including Indigenous and First Nations communities, is carried out under mandated policy.

“An impact assessment is a planning and decision-making tool used to assess the potential positive and negative effects of proposed projects,” according to the Government of Canada website.

The Impact Assessment Act (IAA) was implemented in 2019 under Justin Trudeau’s Liberal government after former prime minister Stephen Harper’s environmental assessment regime was widely criticized for not being strong enough. The Act allows the Ministry of Environment and Climate Change (MECC) to step in on “designated projects” that are defined in the Project List, or those that may cause adverse effects within federal jurisdiction, subjecting them to a lengthy federal review.

Federal Cabinet has the ultimate say over which designated projects will continue to the review stage based on factors including “the extent to which the designated project contributes to sustainability”, “the impact that the designated project may have on any Indigenous group”, “the extent to which the effects of the designated project hinder or contribute to the Government of Canada’s ability to meet its environmental obligations and its commitments in respect of climate change” and “any other matter relevant to the impact assessment that the Agency requires to be taken into account”.

In implementing the IAA, provincial political leaders, led by the Alberta government, ignited a legal challenge arguing that the Liberal government had gone too far in the other direction and, in doing so, was overstepping its jurisdiction to undertake a review of provincial infrastructure projects.

“From the proponent’s perspective, designation under the IAA means delay, additional regulatory costs and uncertainty as to whether political decision-makers will permit a project to proceed based on the federal policy priorities of the day,” a team of legal counsel with Osler Law Firm, who wrote a synopsis of the decision, stated.

The IAA has been largely controversial, dubbed by former conservative premier of Alberta, Jason Kenney, as the “no more pipelines act” — as the political spectrum continues to battle it out over cross national pipelines that could contribute to economic prosperity while harming the natural environment. In 2019, backed by the governments of Saskatchewan, — under Premier Scott Moe of the right leaning Saskatchewan Party — Ontario, — under Conservative Premier Ford — and three First Nations, Kenney filed a case with the Alberta Court of Appeal which, in a 4-1 decision, called the Act an “existential threat” to the Canadian Constitution.

In the wake of the non-binding decision by the Aberta court, the federal government appealed to the Supreme Court, a case which was heard in March. On October 13, the Supreme Court issued a 5-2 decision ruling the Act is largely unconstitutional, a shock to the feds, environmental organizations, and those who practice and follow constitutional law. Chief Justice of the Supreme Court of Canada Honourable Richard Wagner wrote for the majority in the decision that projects carried out or financed by federal authorities on federal lands or outside of Canada fall under federal jurisdiction and remain constitutional.

The problem with the “designated projects” portion of the legislation is with the scope of which projects are amassed under federal authority and why. 

“Environmental protection remains one of today’s most pressing challenges. To meet this challenge, parliament has the power to enact a scheme of environmental assessment,” Justice Wagner wrote. “Parliament also has the duty, however, to act within the enduring division of powers framework laid out in the Constitution.”

Following the release of the decision, Minister of Environment and Climate Change, Steven Guilbeault, stated the federal government respects the decision made by the Supreme Court and it would be working with the court’s guidance to improve the legislation, committing to outlining a concrete plan by the end of the year. As an advisory decision, the ruling does not force the feds to make any changes to the Act, rather it serves as a warning that failure to do so could result in further legal challenges.

Despite the setback by the decision, the federal government is not succumbing to the demands of right-leaning premiers, and remains committed to achieving the national target of a 45 percent reduction in greenhouse gas emission, below 2005 levels, by 2030 and net zero emissions by 2050 — meanwhile, across Canada, emissions rose 2.1 percent in 2022.

"We accept the court's opinion. It provides new guidance on the Impact Assessment Act, while explicitly affirming the right of the government of Canada to put in place impact assessment legislation and collaborate with provinces on environmental protection," he said.


On October 13, the Supreme Court of Canada issued a 5-2 decision supporting the previous decision made by the Alberta Superior Court that struck down sections of the federal Impact Assessment Act as unconstitutional.

(Supreme Court of Canada)


Following the release of the decision, dissenting opinions in the environmental space were put forward.

“Federal oversight is crucial, given that environmental issues are not contained within provincial borders,” Keith Brooks, program manager at Environmental Defence, wrote in a statement following the release of the decision. “And it’s especially crucial when provinces aren’t taking environmental responsibility seriously or, as the case may be, are outright hostile towards environmental protection.”

Ecojustice, the environmental law organization which has represented youth in two fights against the Ontario government and the federal government, as well as intervening on several provincial challenges of the federal carbon tax, said that while the decision is disappointing, it “confirmed that no project is immune from environmental scrutiny.”

“It is important that Canada moves forward with other important environmental priorities, including an oil and gas emissions cap, a thermal coal export ban, biodiversity legislation and a ban on single-use plastic,” Ecojustice lawyer Joshua Ginsberg said.

Others are viewing the decision as a major win for conservative governments that have long challenged the Liberal’s environmental policies for being too damaging to the economy and for stepping on the authority of provinces. Alberta saw widespread support for the Supreme Court decision after it solidified what had been decided in its highest provincial court. Both Premier Danielle Smith and former premier Kenney made bellowing statements following the release of the decision, celebrating a victory they believe will allow the province to prosper.

“If you believe in fairness, common sense and the sanctity of the Canadian Constitution, today is a great day. We are extremely pleased with the Supreme Court of Canada’s decision confirming the unconstitutionality of the federal government’s destructive Impact Assessment Act,” Smith said. 

The ultra-conservative premier has publicly stated she plans to continue to challenge the federal government, threatening the incoming cap on emissions from the oil and gas sector, and the draft Clean Energy Regulations (CER). 

“They will damage our economy. They will stifle development. They will erode constitutional rights. And they will ultimately harm all Canadians by putting jobs at risk and making life more expensive,” she stated, with no evidence to back up how these cuts will play out. Smith has been asserting Alberta’s independence from the federal government in a quest to establish itself as an autonomous nation.

The government of Saskatchewan stands behind Alberta in celebrating the decision, saying the IAA has “stalled everything from Canadian highway and mine projects to LNG facilities and pipelines,” thwarting “investment, competitiveness and productivity across the country”.

“This decision is nothing short of a constitutional tipping point,” Saskatchewan Justice Minister Attorney General Bronwyn Eyre said in a statement following the decision. 

The western provinces are backed greatly by the oil and gas industry, both of which put out statements relishing the decision. Oil and gas producers have largely stood in opposition to the Liberals who have imposed stricter targets for emissions reductions and pipeline controls. 

Premier Doug Ford also welcomed the decision, claiming the Ontario government can hold itself accountable for environmental assessments. 

"The federal impact assessment process needlessly duplicated Ontario's rigorous and world-leading environmental assessment requirements," he stated. 

The statement has left some members in the public concerned, coming from a province that has been moving backward since the election of the PCs in 2018, scaling back emissions reductions targets while simultaneously ramping up the production of natural gas. 


Natural gas made up 10.4 percent on Ontario’s energy outputs in 2022.

(Rachel Morgan/The Pointer)


When elected in 2018, Ford made a commitment to decrease the use of natural gas within the Made In Ontario Plan which forecasted 3.5 megatonnes of carbon reductions from natural gas conservation, the one environmental move the province’s Auditor General said had “merit”. But the PCs quickly turned their back on this promise in 2020 and presented new modelling forecasts with a measly 0.3 megatonnes in reductions. 

An analysis completed by Environmental Defence found that in 2030, Ontario’s emissions will be hovering around 160 megatonnes, 16 megatonnes higher than the provincial target — a target that was already watered down significantly from the former Liberal government’s aspired reductions.

While the province continues to produce emissions at high rates, stifling mitigation measures, the Ford government is reducing the mandate of conservation authorities and municipalities to comment on environmental assessments, dampening the ability to build sustainably while focussing on infrastructural adaptation.

In 2020, the Ford government passed Bill 229 with the highly contentious Schedule 6 which began to chip away at the authority of conservation authorities. This was amplified in 2022 with the passing of Bill 23, which made significant changes to the Wetland Evaluation System, increasing the likelihood of building in sensitive wetland habitats, all the while limiting conservation authorities for commenting on development applications using arguments such as “pollution” or “conservation of land”.

The reason the PCs have given for each of these legislative changes is that more land is needed in order to provide 1.5 million new homes for Ontarians by 2031.

"At a time when it's never been more important to build critical infrastructure, including highways, transit, and critical mineral projects, we now have the certainty we need to get shovels in the ground," Ford stated.

But the claim by the Premier is misleading.

One of the most contentious projects pushed by the Ford government was the reestablishment of the 413 Highway which will run from Milton, up the west end of Brampton, through the south end of Caledon slicing through the Greenbelt, and into Vaughan.

In May 2021, the federal government designated the GTA West Highway, as the project is commonly known, for an Impact Assessment, which has stalled the project from proceeding.

Currently the project is at a standstill. A spokesperson for the IAA told The Pointer in an email statement that in order for the impact assessment process to begin, the Ministry of Transportation (who proposed the project) must submit an Initial Project Description (IPD). Until the IPD is submitted, the process can not formally begin — The IAA has been waiting on the IPD for over two years, although there is no set deadline on when the proposal must be submitted.

Once the Ministry of Transportation has satisfied the requirement with a satisfactory IPD, the IAA will begin the planning phase for the project, including public and Indigenous consultation which will allow these groups to review a summary of the IPD and submit feedback related to the proposal, the spokesperson said. It is also during this phase when the agency will decide whether a full impact assessment is required. Once the formal process begins, it can take between two and five years for the assessment to be completed. 


In addition to harming the habitats of species at risk, Highway 413 will also bisect vital farmland.

(The Pointer files)


“Ontario is a growing province and needs to build new critical infrastructure, including Highway 413, the Bradford Bypass, and transit projects across the province to realize the more prosperous society that renews the promise of Ontario for future generations,” Nadia Todorova, executive director of the Residential and Civil Construction Alliance of Ontario, published in a statement following the Supreme Court decision.

But the Ford government has not come out and said the ruling will allow Highway 413 to continue without assessment, and by careful reading of the decision and the legislation, legal representatives have said this is because it is not the case.

In its decision to designate the GTA West Corridor for an impact assessment, the Ministry of Environment and Climate Change and the IAA cited the project's overlap of federal jurisdiction when it comes to species at risk and Indigenous consultation. A previous investigation by The Pointer found 29 species at risk residing within the proposed route of the highway whose habitats would ultimately be impacted by its construction.

“The Minister has reached the decision that the designation of the Project is warranted as the Project may cause adverse direct or incidental effects on the critical habitat of federally-listed species at risk that may not be mitigated through project design or the application of standard mitigation measures, or through existing legislative mechanisms,” Minister Guilbeault wrote in his reasoning for designating the project.

But while the Impact Assessment is a crucial tool for holding provincial governments accountable for adhering to stricter environmental standards, the federal government itself has not been consistent in its use of the regulatory tool. 

The 413 Highway was eventually designated for assessment after immense pressure and backlash from the public, but the tool has not been imposed on its sister highway, the Bradford Bypass.

“I wasn’t blown away by the sophistication of their analysis of our actual impact assessment request for both Highway 413 and the Bradford Bypass,” Laura Bowman, legal counsel for Ecojustice previously told The Pointer, referring to the effectiveness of the Impact Assessment Agency in the case of the 413 highway and the Bradford Highway. “There were a lot of errors in that analysis, a lot of things that were misunderstood about the project and about the mitigation measures or those projects.”

The Bradford Bypass, also known as the 400-404 Link is proposed to span 16.2 kilometers in the northern reaches of the GTA from West to East Gwillimbury. The idea was developed back in the 70s and 80s but was shot down by subsequent provincial governments before being reimagined by the Ford government. While the highway is relatively short, its list of potential environmental consequences is far from the same. The 400-series highway threatens species at risk, wetland habitats and intersects traditional Indigenous territory. The proposed route runs directly through the Greenbelt and rams into the Holland Marsh and the edge of the Lake Simcoe watershed. 

While no formal analysis has been completed, it is arguable that on a per kilometre basis, the Bradford Bypass could have an even greater negative impact on the environment compared to the GTA West Corridor, largely due to the Holland Marsh providing one of the most fertile landscapes across the province. Yet, despite similar involvement from local activists and environmental organizations, the Bradford Bypass has not met the same fate as Highways 413, begging to question the validity of the criteria under which projects are chosen.

Federal Minister of Natural Resources, Jonathan Wilkinson, stated following the Supreme Court decision that the Trudeau government sought to improve the impact assessment process that was failing under the Harper government. It is something that has been celebrated internationally.

“While Canada needs to continue to work to make their processes run as effectively and efficiently as possible, I would note that already many of our international allies look to Canada as a model of how regulatory processes should work,” he said.

Regardless, the federal government is committed to working with their provincial and Indigenous partners to establish a regulatory framework that suits all needs.

“We will now take this back and work quickly to improve the legislation through parliament,” Minister Guilbeault said. “We will continue to build on 50 years of federal leadership in Impact Assessment.”

According to the IAA, there are currently 23 projects within various stages of the impact assessment process. While it remains unknown what will happen to each individual project, the federal government remains on the upper hand, and has the constitutional right to oversee a process for environmental regulation.

Brooks for environmental Defence noted that, despite the claims of conservative Premiers, ecological degradation is not fair game.

“We note, too, that this is an advisory ruling,” he said. “The Impact Assessment Act remains in force.” 



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