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I was surprised over just how few spaces there were for cars. Nine? For more than 700 units? I told my colleague Emily Chung, who wasn’t surprised at all. She explained that, until recently, the City of Toronto had mandatory parking minimums, where buildings were required to have a certain number of parking spaces depending on their size.
It turns out that more and more cities in North America are removing these minimums. And the good news is that it’s great for the climate and the environment.
Let’s talk about parking when it comes to condominiums and apartment buildings rather than above-ground parking for malls and homes, since big cities are continually building up rather than out.
A 2022 study for the City of Vancouver estimated that a decrease of 10 underground parking spaces could reduce CO2 emissions between 50 tonnes to as high as 8,500 tonnes.
They also noted that the minimum impact of constructing one parking space is almost equal to one year of the operation of a car, and the maximum impact is close to the operation of a car for close to 19 years.
That’s a lot of CO2 emissions.
“For each level of parking you remove, you can reduce the [greenhouse gas emissions] of a building by about 15 per cent,” said Shoshanna Saxe, an associate professor at the University of Toronto’s department of civil and mineral engineering and Canada Research Chair in Sustainable Infrastructure.
“The simplest, easiest thing you can do to make your building more sustainable is not have a whole bunch of underground parking.”
Another study, by the Canada Mortgage and Housing Corporation (CMHC) that was released in 2024, noted that the environmental impacts of constructing underground parking spaces are far-reaching, including the displacement of soil that is taken elsewhere and potentially passing on dangerous microorganisms, including e.coli.
And removing the soil also means a larger carbon footprint as these trucks may need to drive hundreds of kilometres to dispose of it.
And let’s not forget that once the ground is dug up, trapped CO2 is also released into the atmosphere.
Now, while cities across Canada and the U.S. are moving away from these parking minimums, they’re not doing so for the climate or the environment, Saxe noted.
It’s the cost.
A 2024 study by the Altus Group, which provides asset and fund information for commercial real estate, found that building underground parking in Vancouver ranges anywhere from $160 to $250 per square foot. For comparison, surface parking would cost between $12 to $25 per square foot. In Toronto, underground parking ranges $175 to $300 per square foot, while surface parking ranges from $15 to $30.
Reducing parking minimums means housing becomes more affordable.
“Before Toronto rolled back mandatory minimum parking requirements, you were seeing … lots of buildings where they had way more parking than anybody wanted,” Saxe said. “People just wouldn’t claim them, and they have to be absorbed, in general, by the costs in the building.”
The CMHC study also noted that there is less need for parking minimums, as our lifestyles have changed. More people are turning to ride shares, they noted. And after the COVID pandemic, more people are working from home, even if it’s only part of the time.
Of course, getting rid of parking means there needs to be a robust transit system in place, something that some cities, like Toronto, are aiming to improve by building new transit lines. Bike lanes are another important factor, she noted.
Finally, Saxe said that we need to stop making driving such an attractive method of getting around.
“People behave within the system that we build for them. And so if we say this is a place you get to by parking, we signal it with providing a lot of parking,” she said. “Then we’re incentivizing people to drive, which leads to more air pollution of all kinds.”
Saxe said she is happy to see more cities move away from mandatory parking minimums.
“I think that in many ways, while it was driven by cost, getting rid of mandatory minimums is one of the best sustainability policies that’s been passed in many cities around North America in the last 10 years,” she said.
— Nicole Mortillaro
Old issues of What on Earth? are here. The CBC News climate page is here.
Check out our podcast and radio show. In our newest episode: Climate-friendly menstrual products come with a lot of complex considerations, like personal preferences, stigma and cost. We visit a start-up in Nova Scotia that’s making compostable pads. Then, we hear about the policy and social changes that could help make sustainable options more accessible.
What On Earth drops new podcast episodes every Wednesday and Saturday. You can find them on your favourite podcast app or on demand at CBC Listen. The radio show airs Sundays at 11 a.m., 11:30 a.m. in Newfoundland and Labrador.
Have a compelling personal story about climate change you want to share with CBC News? Pitch a First Person column here.
We received more mail about the student science project to test eco-friendly laundry water for watering garden plants.
While some readers said they water houseplants or fill the toilet tank with “grey water” from things like bathing, Marek Gomolka, a septic system specialist in Victoria, B.C., cautions that discharging household grey water outside is often prohibited by public health regulations. “More importantly, untreated grey water can return and contaminate aquifers, streams and so on,” he wrote.
Michael Storoszko wrote: “Did you know that automatic washing machines, about 40 years ago, recycled laundry water? My mother’s washing machine would drain the grey water into the utility sink after washing one load and when the next load started, it would suck up the water and reuse. My mother never had a complaint about how clean the whites were or how bright the coloured clothes came out after washing this way. She missed this feature when she had to replace the machine after more than 25 years of service! Perhaps washing machine manufacturers should consider reintroducing this feature?”
Write us at [email protected]. (And feel free to send photos, too!)
The NASA satellite image above shows Antarctic ice extent at its annual low on March 1, 2025. This year’s was the second-lowest on record — the yellow line shows how it compares to the median between 1981 to 2010. Meanwhile, in the Arctic, sea ice in February hit its lowest level on record for that month, thanks to a heat anomaly at the beginning of the month that caused temperatures to soar 20 C above average and above the melting point. Together, the dwindling ice at both the North and South Poles led to a global record for lowest sea ice extent on Feb. 5, the EU’s Copernicus Climate Change Service reported. The loss of sea ice worries scientists because the white ice reflects sunlight, while darker water absorbs more heat, speeding up climate change. CBC’s Susan Ormiston and Jill English recently returned from a Canadian scientific mission in Antarctica, where they reported on how Antarctica’s ice and cold oceans play an outsized role in regulating the global climate.
— Emily Chung
Blue Himalayan poppies. Rhubarb. Garlic. Spring has sprouted two weeks early in Newfoundland.
Offshore wind turbines serve up buffet tables for some fish, according to new research.
Has the palm tree’s Hollywood reign come to an end? Some say the iconic tree is too risky for fire-prone Southern California.
Canadians worry about climate change as insurance costs rise.
Jersey City, N.J., residents can swap depleted e-mobility batteries for new ones at micromobility parking and charging stations — a U.S. first.
A small town in Quebec’s Montérégie region is trying a novel approach to help mitigate the impacts of climate change and accelerate the greening of the community.
As of 2025, homeowners in Saint-Amable, Que., roughly 40 kilometres east of Montreal, are being charged an annual surtax of $200 if they don’t have at least one leafy, deciduous tree in their front yard.
A recent report out of Université Laval showed the town’s high vulnerability and exposure to extreme heat events.
Saint-Amable general manager Jean-Sébastien Ménard said the report was a wake-up call.
“It was like a punch,” he said.
Ménard said the eco tax was put in place to encourage residents to adopt more environmentally friendly behaviours and plant more trees.
The trees, he said, are needed to combat the phenomenon of heat islands.
Heat islands can lead to the deterioration of air quality and can also adversely affect human health and well-being, increasing the burden on health facilities.
The money collected from the tax is being reinvested into greening initiatives in the municipality, Ménard said.
New urban developments often lack tree cover
At first glance, it might be surprising to find that a small town with a population of 13,322, nestled among agricultural fields, is grappling with heat islands. But a closer look reveals the real issue.
“There’s a definite lack of large trees,” said David Wees, a faculty lecturer with McGill University’s department of plant science.
He added it’s not uncommon in new urban developments.
According to Centris.ca, an online real-estate brokerage website, 45 per cent of homes in the area were built after the year 2000, including 14 per cent that were built after 2011.
“This is a new suburb,” Wees said. “And while it’s true there’s a lot of lawns, large trees have a much bigger impact on the climate than lawns do.”
What’s happening, he said, is that all the streets, all the parking and all the roofs on buildings are absorbing solar radiation during the day and re-radiating it out at night so the air heats up.
Trees help reduce air temperature by providing shade and evaporating water, but that’s not all they do.
Trees, Wees said, have other benefits such as reducing wind speed, absorbing certain air pollutants and capturing rainwater.
“So every time it rains, instead of all that rain going into the sewage, storm sewers or flooding people’s homes, the trees absorb large portions of it,” he said.
Tree tax ‘makes sense’
Ménard said , however, the main impetus for the tax was to speed up the greening process.
“We need to double our canopy,” he said. “We have a lot of catching up to do.”
While Ménard said the one-tree rule isn’t new, it was never really observed or enforced before.
The town teamed up with mapping service Jakarto and used artificial intelligence, sending out tiny vehicles equipped with cameras to go up and down neighbourhood streets to detect the presence of trees.
That was done in 2024 with notices sent out to about 1,200 properties that were found to be non-compliant. Of those, 800 took the necessary steps to plant a tree, Ménard said.
The plan is to send out the vehicles again this spring.
Growing pains
While Ménard is touting the success of the initiative, there have been some issues with its implementation.
Caroline Skucas said she was a bit confused when she received a notice from the town saying she wasn’t in compliance with the rules.
“There wasn’t really room to negotiate. We have like a huge tree in the front and they’re like, ‘Oh it has to be in the back,'” she said.
Skucas ended up planting two apple trees, but said she felt it was an imposition.
She said there’s not much space in her backyard, and with the large tree in the front and a cedar hedge around the property, she wouldn’t have chosen to add more trees.
Ménard clarified that in certain cases, like when a home is located on a street corner, there will be tree requirements for parts of the yard facing the public street — even if it’s in the back.
The type of tree people plant is also important, with Ménard specifying that shrubs don’t qualify as trees.
Wees agreed it made sense.
“If your main goal is to reduce the heat-island effect, the bigger the better,” he said. “More leaves, more shade, and so on and so forth.”
Despite some bumps in the road, Ménard said he’s confident that by the end of the year, all remaining properties will be tree compliant.
He added the municipality is also doing its part by planting 12,000 trees on public land.
— Annabelle Olivier
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Editors: Emily Chung and Hannah Hoag | Logo design: Sködt McNalty
