How homes could be retrofitted to float during floods

Hello, Earthlings! This is our weekly newsletter on all things environmental, where we highlight trends and solutions that are moving us to a more sustainable world. (Sign up here to get it in your inbox every Thursday.)

This is our last issue of What on Earth? for 2021. Thank you so much for reading the newsletter this year. We'll be back on Jan. 6. Until then, enjoy a safe and happy holiday.

This week:

• How homes could be retrofitted to float during floods
• Take a look at these zero-waste Christmas trees
• Quebec entrepreneur donates cherished island after protecting it from city sprawl

How homes could be retrofitted to float during floods

As climate change boosts the risk of flooding, researchers have come up with a way that some communities could adapt — by retrofitting their homes to float above the floodwaters.

Elizabeth English, founder of the Buoyant Foundation Project, said it's a strategy to reduce the risk posed by flooding. 

The project, which conducts research to make low-income housing "amphibious" with such retrofits, was founded in 2006, after whole neighbourhoods of New Orleans were inundated in the wake of Hurricane Katrina.

"The technology itself is actually very simple," said English, who is also a professor of architecture at the University of Waterloo in southern Ontario.

Buoyant floats are installed underneath the main floor of the house. Then, vertical guide posts are added next to the house and attached to it. That way, it will only move up and down and not side to side. During a flood, the house rises with the floodwaters. When the floodwaters recede, it sits back down on the foundation.

English said it is simple and inexpensive for single-storey, lightweight homes with no basement that are elevated above the ground: "I think we can do it for $20 a square foot, plus or minus."

It's possible for larger houses and homes with basements, too, but is more expensive and you would lose the use of the basement as anything but a crawl space.

So far, the Buoyant Project has done four retrofits for rice farmers in Vietnam, and is in talks with some First Nations communities in Canada to develop a system that could work for their specific needs.

Despite taking inspiration from the flooding in New Orleans, the project hasn't yet done any retrofits in Louisiana. That's because until now, all amphibious construction was prohibited in the United States. English said there were worries the technology would give developers licence to turn wetlands and floodplains into new housing complexes.

English lobbied the U.S. agency in charge of disaster response to allow retrofitting a house if the cost of the retrofit was less than half the value of the house, and succeeded. However, she said any house that has amphibious construction is ineligible for flood insurance, discouraging retrofits.

There are, of course, other strategies for dealing with housing in a time of rising water levels. 

For example, "float homes" have been built directly on the water in Vancouver and Amsterdam. Existing homes can be permanently elevated, although that causes other problems such as increased risk during heavy winds.

Another approach is building protective structures such as dikes or levees that control water flow. But English said there's only so much you can do to control water, as the example of New Orleans showed — it flooded when its levee system failed.

In flood-prone areas, governments generally advocate retreat — that is, simply abandoning the homes and properties there.

"If you're OK with leaving where you live and going someplace else, that's probably the easiest thing to do," English said. "But I typically work with populations for whom moving away is culturally not an option ... they're so tied to the land."

– Emily Chung

Reader feedback

We received a lot of mail about Emily Chung's article on the environmental impacts of traffic congestion and possible solutions. 

Some readers, such as Jim Bodie of Sherwood Park, Alta., pointed out a flaw in the estimated health and greenhouse gas impacts of the proposed Ontario Highway 413 by 2050, as cited in the article: they don't take into account that all new cars and light-duty trucks sold in Canada will be required to be zero-emissions by 2035. 

While that would reduce the emissions and pollution caused by the highway, highlighting the co-benefits of electric vehicles, it wouldn't address other highway and vehicle impacts, such as increased vehicle-related injuries and deaths or destruction of natural carbon sinks.

Other readers, such as Eric Doherty, a registered professional planner in Victoria, noted that adding better transit, cycling and pedestrian infrastructure can do far more than give people alternatives to sitting in traffic (even if it doesn't speed up travel times for cars). If it reduces car lanes and road space for cars, it also reduces the overall number of vehicles on the road via "traffic evaporation," which is basically the reverse of "induced traffic." And that, of course, reduces negative impacts such as pollution, emissions and injuries and deaths from vehicle collisions. 

Finally, Philip Lucas pointed to another congestion-cutting solution, which we've written about before: cutting the speed limit. "We could simply reduce the speed limits on 400 series highways within 50 km of the cities to 80 or 70 km/h. This reduces emissions and pollution, reduces accidents and gridlock and generally makes people think about transit as a faster way to get into town. The cost is almost free, the benefit is great for the environment, the car, the driver and the city."

Write us at whatonearth@cbc.ca.

Old issues of What on Earth? are right here.

There's also a radio show and podcast! A heat dome, atmospheric rivers, flooding… 2021 was full of extreme weather events. CBC meterorologists Johanna Wagstaffe, Fiona Odlum and Ryan Snoddon pull back the curtain with What on Earth host Laura Lynch about the year that's been and how they balance forecasting, communicating climate change and their own mental health. What On Earth airs Sunday at 12:30 p.m., 1 p.m. in Newfoundland. Subscribe on your favourite podcast app or hear it on demand at CBC Listen.

The Big Picture:  Zero-waste Christmas trees

All Christmas trees, whether real or fake, have an environmental impact, ultimately generating waste. And living Christmas trees aren't an option for many people. So Canadians in the zero-waste community have been turning to some creative alternatives.

Kriti Murthy, a member of the Zero Waste Toronto Facebook group, posted a photo of her tree from last year (below, left), hanging on the glass door of her home in New Jersey. It's made from sticks and pieces of broken Christmas wreaths. When her family of four moved to Burlington, Ont., this spring, they passed it on via a local Buy Nothing group. "Hopefully, it's hanging on our friend's door this year," she said.

Another member of the Zero Waste group, who goes by the name Feu DeVie shared a similar concept (right). While living in a tiny home near a river, she had no space for a regular Christmas tree. Then her mother showed her a clipping from a design magazine that they decided to replicate. The two of them collected driftwood and cedar branches nearby to create their own version. 

It has since become a tradition, and Feu DeVie has a tree like it up now. "Even when I've had the space, I much prefer this style," she said, adding that space, esthetics and environmental considerations all come into play.

Hot and bothered: Provocative ideas from around the web

• Sea level rise as a result of climate change is hastening erosion. Now, erosion is digging buried waste out of old landfills, and could dump tons of this "zombie garbage" into the world's oceans.

• How can you use your money most effectively to fight climate change? The Atlantic explains why some advocates endorse giving to organizations that lobby for strong climate policies, and why that approach is different from the approach to the world's health problems.

• An album of bird noises has cracked the Top 5 in Australia, besting holiday stalwarts like Mariah Carey and Michael Bublé. The record, entitled Songs of Disappearance, was captured over four decades, and features the calls and songs of 53 endangered species, including the night parrot and the regent honeyeater. All proceeds will go to BirdLife Australia.

Quebec entrepreneur donates cherished island after protecting it from city sprawl

For most of his adult life, Thor Vikström has watched the seasons change and the birds come and go from his small island, which sits opposite his riverside home in Laval, Que.

At 93, he says he's at peace knowing the land — nestled between Montreal and Laval — will remain protected long after he's gone, now that he's donated it to the Nature Conservancy of Canada.

Called Île Ronde, the nearly three-hectare island sits in the middle of Rivière-des-Prairies, near Lake of Two Mountains, where the Ottawa and St. Lawrence rivers meet. Wedged between two major cities, it's easy to miss. But its forest and marshland are teeming with biodiversity. 

Vikström has owned and cared for the land since the late 1960s, when he built his family home in Laval and fell in love with his view of the island. He convinced its former owner to sell so he could keep it untouched. His recent donation ensures it will be protected for generations to come.

"I trust my children; I'm sure they'll protect the island. But what happens after my children [are] gone?" Vikström said. "It's just a good feeling in my heart. I know this will be there forever."

Vikström and his late wife moved to Canada from Sweden with their first-born son in 1962 and built a life in Quebec, eventually founding Scanada, a successful family company.  As an entrepreneur in the hydraulics industry, Vikström was in the business of building up. (He was even consulted on the construction of the CN Tower in Toronto.) 

But he has refused to let city sprawl onto his treasured island. Developers have come knocking on his door over the years, asking him to sell, but Vikström turned them all away. 

"I bought the island because I couldn't see it destroyed," he said.

"Nature was more important than some stupid money in my pocket," he added. "I said, 'This is something [that's] got to be preserved,' and I kept my word."

For the Vikström family, the island was a getaway over the years; they had a cable ferry built to access it and often invited neighbours and friends to join them there. At one point, they kept sheep on the island for grazing. Vikström said he had the idea that the animals would keep the bushes and weeds at bay.

Nowadays, Île Ronde has mostly been left to its natural state. 

As Canada works toward its goal of protecting 30 per cent of land and water by 2030, Vikström said he is glad to have played a part.

The Nature Conservancy of Canada is also helping, through gifts of land, like this one, and purchases. The private, not-for-profit organization recently acquired a large parcel of grassland in southern Saskatchewan and more than 7,000 hectares of Ontario's Manitoulin Island.

Île Ronde is home to the northern map turtle, a species that is federally designated as being of special concern and as vulnerable in Quebec.

Biologist Sébastien Rouleau, who researches map turtles and has visited Île Ronde in the past, said the donation of the island, with its natural shoreline, is particularly great news for the turtles, which are sensitive to human activity.

"Turtles don't climb concrete walls really well, so having access to the natural shoreline will give them natural nesting sites, as well as basking opportunities, which is essential for their living," said Rouleau, who co-ordinates research and conservation at the Zoo Ecomuseum in Sainte-Anne-de-Bellevue, Que.

The island is also home to a unique tree species, called the shagbark hickory, as well as a variety of waterbirds, including wood ducks, American wigeon and gadwall.

While the island's financial value is relatively low because it's located in a flood-risk zone, the Nature Conservancy says what counts is its value for flora and fauna.

"I think we can pack a lot of biodiversity in a single hand — and imagine an island of that size," said Joël Bonin, associate vice-president of development and communications for the Nature Conservancy of Canada's Quebec chapter.

Although winter has now set in on the island, Vikström said he is already looking forward to watching the migratory birds return in the spring — as he has for more than 50 years.

– Jaela Bernstien

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Editor: Andre Mayer | Logo design: Sködt McNalty