With each passing summer, the heat feels different, more relentless, more dangerous, and more difficult to ignore.
What was once seen as seasonal discomfort is now a growing public health emergency. Climate change is intensifying the length, frequency, and severity of heat waves in Ontario and across Canada, pushing people and public systems to the brink.
Extreme heat isn’t just about rising temperatures; it’s about the growing risks to human health. Prolonged exposure to high indoor or outdoor temperatures can cause heat-related illnesses like heat exhaustion or heat stroke, worsen chronic conditions such as asthma, cardiovascular disease and mental health challenges, and in many tragic cases, lead to death. In fact, the Government of Canada identifies extreme heat as the leading cause of weather-related fatalities in the country.
But not everyone is equally impacted. The impacts of extreme heat fall hardest on those already facing systemic barriers and marginalization. These include tenants in poorly maintained buildings, children in underfunded schools, people in institutional settings such as prisons, people experiencing homelessness and those without access to cooling. Our laws, whether they govern housing, schools, workplaces or prisons, haven’t kept pace with the climate crisis. And in the absence of adequate policy, communities are left to try to cope alone.
Here are some of the groups most at risk:
- Children in Schools/Child Care Facilities: Overheated classrooms and child care centres threaten children’s physical health and compromise their ability to learn. Many buildings lack ventilation or cooling, revealing gaps in education and public health policy.
- Tenants: Renters, especially those in aging apartments, face dangerously high indoor heat. With no maximum indoor temperature standard in residential housing, many have inefficient cooling, have to pay out of pocket for cooling devices, or worse, go without.
- Migrant Agricultural Workers: Often housed in temporary, substandard conditions, migrant agricultural workers are frequently exposed to extreme heat in their housing and in their work, with little regulatory protection or ability to speak out.
- Prisoners: People incarcerated in overcrowded, poorly ventilated facilities are often subjected to extreme indoor heat without relief. This is a matter of basic human rights and health equity.
- Indigenous Schools and Communities: Many Indigenous communities face even greater impacts from heat due to being chronically underserved and underfunded for infrastructure and health services.
To meet this challenge, we need bold systemic action. Governments at all levels must modernize laws and regulations to reflect the realities of a warming climate. This includes setting maximum indoor temperatures in housing, schools and workplaces, providing cooling in institutional settings, ensuring heat protection plans for outdoor and precarious workers and investing in retrofits that improve safety without displacing tenants or raising rents.
This is not just a climate issue. It’s a health and justice issue. Awareness campaigns and individual action can help but the solutions must be structural, and rooted in law, equity and the right to safe living and working conditions.
Extreme heat won’t wait for policy to catch up. And it won’t end when the summer does.
The heat wave some of us experienced in Southern Ontario this week is a clear signal that climate change is already here and without urgent action, those least protected will continue to bear the highest cost.
June 2025 Newsletter – Intervenor, Volume 51, Number 4
A PDF version of this newsletter is found on the Canadian Environmental Law Archive website; click here to open it in a new tab
Extreme Heat is a Public Health Emergency — Not Just a Weather Event
With each passing summer, the heat feels different, more relentless, more dangerous, and more difficult to ignore.
What was once seen as seasonal discomfort is now a growing public health emergency. Climate change is intensifying the length, frequency, and severity of heat waves in Ontario and across Canada, pushing people and public systems to the brink.
Extreme heat isn’t just about rising temperatures; it’s about the growing risks to human health. Prolonged exposure to high indoor or outdoor temperatures can cause heat-related illnesses like heat exhaustion or heat stroke, worsen chronic conditions such as asthma, cardiovascular disease and mental health challenges, and in many tragic cases, lead to death. In fact, the Government of Canada identifies extreme heat as the leading cause of weather-related fatalities in the country.
But not everyone is equally impacted. The impacts of extreme heat fall hardest on those already facing systemic barriers and marginalization. These include tenants in poorly maintained buildings, children in underfunded schools, people in institutional settings such as prisons, people experiencing homelessness and those without access to cooling. Our laws, whether they govern housing, schools, workplaces or prisons, haven’t kept pace with the climate crisis. And in the absence of adequate policy, communities are left to try to cope alone.
Here are some of the groups most at risk:
To meet this challenge, we need bold systemic action. Governments at all levels must modernize laws and regulations to reflect the realities of a warming climate. This includes setting maximum indoor temperatures in housing, schools and workplaces, providing cooling in institutional settings, ensuring heat protection plans for outdoor and precarious workers and investing in retrofits that improve safety without displacing tenants or raising rents.
This is not just a climate issue. It’s a health and justice issue. Awareness campaigns and individual action can help but the solutions must be structural, and rooted in law, equity and the right to safe living and working conditions.
Extreme heat won’t wait for policy to catch up. And it won’t end when the summer does.
The heat wave some of us experienced in Southern Ontario this week is a clear signal that climate change is already here and without urgent action, those least protected will continue to bear the highest cost.
Case Updates
Hearings Resume for License Renewal at Darlington Nuclear
Hearings resumed this week in the Canadian Nuclear Safety Commission’s (CNSC) two-part process to consider an application from Ontario Power Generation (OPG) to renew the license for the existing nuclear reactors at the Darlington Nuclear Generating Station. This hearing concerns existing reactors, and is separate from proposals to build new nuclear.
CELA, Durham Nuclear Awareness, and Slovenian Home Association presented, with lawyer Sara Libman and experts Dr. MV Ramana and Dr. Ian Fairlee, on Wednesday, June 25th. We asked the commission to deny the unacceptable request by OPG for an unprecedented 30-year term for the renewal license. This length of term would reduce opportunity for critical public participation, involvement and transparency in nuclear oversight.
The CNSC is expected to issue its decision on this matter in the coming weeks.
Law Reform Updates
Bill C-5 Poses Risks to Environment, Health, and Indigenous Rights
Bill C-5, specifically Part 2 containing the proposed Building Canada Act (BCA), is facing criticism due to concerns that it could expedite environmentally risky mega-projects while undermining federal laws meant to protect the environment, health, and Indigenous rights.
The BCA would grant the federal Cabinet broad discretion to designate projects as “national interest,” potentially pre-approving them under existing environmental laws and even exempting them from these laws altogether. The fast-tracking of Bill C-5 is occurring despite calls for reconsideration and appropriate consultations from civil society, Indigenous communities, and the public.
CELA is not opposed to legislative attempts to create good green jobs or to facilitate the transition to a sustainable low-carbon (or net-zero) future.
But it must be done properly. CELA advocates the rule of law, fair and democratic processes, intergenerational equity, and the need for transparency and meaningful public and Indigenous participation in environmental decision-making. This is why CELA is fundamentally opposed to the BCA in its current form.
Bill C-5 passed in the House of Commons with several amendments last week, and passed in the Senate on June 26 without further amendment. CELA calls on the government to ensure that its commitments made during the House and Senate proceedings regarding consultation and implementation of this Bill are fulfilled, and strenuously urges them to consult the public about the choice of major projects under Bill C-5.
Bill 17 Passed Before Consultation Period Closed
Ontario recently passed Bill 17, Protect Ontario by Building Faster and Smarter Act, 2025. The bill was fast-tracked, and was passed before the consultation period on the Environmental Registry of Ontario was even closed – making it impossible to consider public input.
Bill 17 will restrict the information and reports that are available to municipalities when they make development decisions and will require that reports prepared by a prescribed professional are automatically accepted as part of a complete application. CELA submitted comments opposing the Bill’s amendments – we recommend ensuring that municipalities are provided with the tools they need to address climate change and build resilient and energy-efficient infrastructure.
CELA also submitted comments on an Environmental Registry of Ontario consultation related to complete application decisions under the provincial land use planning regime, which is impacted by Bill 17. CELA outlines its key concerns and recommendations to ensure that municipal planning decisions remain well-informed, context-specific, and protective of the environment and public safety.
Civil Rules Review
CELA is highly alarmed and has various concerns arising from recently proposed changes to Ontario civil court rules. With Ecojustice, we jointly submitted a brief to the Ontario Superior Court of Justice and Ministry of the Attorney General that focused on costs in public interest cases, judicial review applications, and related matters. Our concerns are that these proposed changes would make access to justice more difficult for low- and middle-income Ontarians.
Great Lakes Chemical Concerns: Sulphates, Radionuclides, and the Framework on Chemicals of Mutual Concern
The Great Lakes Executive Committee (GLEC) recently released its decision that sulphates do not meet the criteria as a Chemical of Mutual Concern (CMC), a designation that is required before consideration is given to develop binational action plans under Annex 3 of the Great Lakes Water Quality Agreement.
This decision comes after sulphates were nominated due to concerns from the Great Lakes Indian Fish & Wildlife Commission (GLIFWC). A key concern was sulphates’ role in converting mercury to methylmercury, which is the most toxic form of mercury. The presence of sulphates in the Great Lakes harms wild rice that is grown and harvested by tribal communities.
The Canadian and U.S. co-leads of the Annex 3 extended subcommittee on CMCs also recommended to GLEC that they recommend that radionuclides do not meet the criteria as a candidate CMC. GLEC is expected to make a final decision on radionuclides by the end of the year. Radionuclides were first nominated as a candidate CMC by over 100 non-governmental organizations and GLIFWC in 2016 and again in 2022; groups throughout the Great Lakes basin will be formally responding to the proposed recommendation over the next two months.
CELA, along with the Great Lakes Ecoregion Network, has expressed concern about the decisions and recommendations regarding sulphates and radionuclides, and about the effectiveness of the current criteria framework to evaluate nominations of CMCs and advance binational action to address harmful chemicals in the Great Lakes.
Inside CELA
55th Anniversary: 1970 - 2025
CELA turns 55 this year! We recently celebrated this milestone with friends and colleagues in a gathering featuring remarks from Rod Strain (Vice President, Clinic Law Services, Legal Aid Ontario) and an inspiring keynote address from Kathleen Padulo (Director of Environment, Chiefs of Ontario). We were delighted to welcome former staff, students, board members and other special guests to the event.
In Memoriam - Sarah Miller
The staff and board members of CELA learned with deep sadness of the passing of Sarah Miller, a remarkable and passionate activist who dedicated her life to environmental advocacy and the well-being of her community. Sarah lived a life truly on her own terms, leaving an enduring legacy in both her professional and personal realms.
Sarah was a coordinator and researcher with CELA for over 25 years. During her time with CELA, she worked tirelessly on toxics reduction, cancer prevention and Great Lakes protection.
Sarah’s passing is a profound loss for her family, her many friends, and the entire environmental community that benefited from her tireless efforts. She was described by a former colleague as, “a treasure, a mentor, colleague and friend,” and “a kindred spirit.” Sarah will be dearly missed and we will forever be grateful for her dedication and passion.
Read the full tribute to Sarah, as well as memories of her friends and colleagues, on our website.
Webinars and Resources
The Limits of “Best Efforts”: Bill C-61, Legislative Failure, and First Nations Water Rights
In 2023, the federal government introduced Bill C-61: The First Nations Clean Water Act, aiming to address longstanding failures in Indigenous water governance.
The bill promised to affirm First Nations’ water rights and set minimum standards for drinking water and wastewater services. Its use of the phrase “best efforts” to describe federal obligations drew concern from Indigenous leaders and legal advocates. While “best efforts” carries recognized legal weight in Canadian contract and administrative law, it remains context-dependent and, without enforceable guarantees, risks perpetuating the same discretion and underperformance that have historically characterized federal water policy for First Nations.
CELA recently published an insightful paper on this topic by Ryan Cho, an undergraduate student in the University of Toronto’s research and ethics program.
We hope a new Bill will be introduced advancing protection of First Nations drinking water in the current Parliament.
Public Legal Education Round-Up
CELA staff made a number of presentations this spring.
CELA Celebrates 40th Anniversary of the Niagara Escarpment Plan
CELA is celebrating the 40th anniversary of the Niagara Escarpment Plan (NEP). Established in 1985 under the Niagara Escarpment Planning and Development Act and administered by the Niagara Escarpment Commission, the NEP is widely praised as the first environmental land use plan in Canada.
The NEP’s protective policies continue to safeguard the important natural heritage and socio-economic values of the NEP area, which extends for 725 km from the Niagara Region to the Bruce Peninsula. The NEP area has also been recognized by UNESCO as an international biosphere reserve.
Over the decades, CELA has been extensively involved in protecting this unique land form, including being a founding member of CONE (Coalition on the Niagara Escarpment), participating in the first 10 Year Review of the NEP, serving as counsel for parties in development appeals involving the NEP, and co-authoring a book on the NEP.
Congratulations to the Ontario government, Commission, and other groups and stakeholders for their collective commitment to protecting the NEP area.
From the Foundation
June Feature
In recognition of CELA’s 55th anniversary, this month’s feature from the Canadian Environmental Law Foundation is the first publication formally published by CELA back in 1971.
Titled “Critique on Proposed Ontario Environmental Act (Bill 94)”, the report was written by then CELA counsel David Estrin. Artfully written, the report opens with the argument
“Any Bill that purports to protect our natural environment must inevitably resolve two conflicting interests. On the one hand, the environmental legislation must recognize the validity of the conservationists’ argument that our natural environment can only be preserved for the future if fairly drastic measures are taken immediately to limit existing and new sources of pollution. On the other hand, the legislation must also take cognizance of the fact that to insist on a pristine pure environment in the 20th Century is both unrealistic and unfair to many segments of society.”
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