sumas-river-tiger-dam-removal
Photo: B.C. Ministry of Transportation and Infrastructure / ​​Flickr

After disaster strikes, how much is it worth to rebuild?

In 2021, flooding in the Sumas Valley caused millions in damages. Rebuilding could cost more than twice as much as restoring the region to its natural state

Some of the most fertile land in southern B.C.’s Fraser Valley is the former lake-bed of Semá:th Xhotsa (Sumas Lake), where water has been held back for a century. The region, which once supported an ancient Indigenous food system, has been home to farms and ranches since it was drained in 1924. But during the disastrous 2021 B.C. floods, part of the lake reflooded again, causing millions in damages. 

A team of researchers, led by the University of British Columbia along with members of the Sumas Nation, analyzed four flood response scenarios proposed by the City of Abbotsford. They concluded it could be cheaper to buy back some private land and reflood part of the former lake-bed — now known as Sumas Prairie — rather than build up the concrete infrastructure necessary to try to keep Semá:th Xhotsa dry forever. “We find that the cost of buying out properties in the lake-bed and allowing the lake to return is close to half the cost ($1 billion) of maintaining the status quo ($2.4 billion),” the authors conclude in the newly-published paper. 

The Semá:th People relied on the lake before it was drained and the Sumas Nation supports further research into flooding part of the lake to support the restoration of the ecosystem and mitigate disasters. But the city made it clear that managed retreat is not an option it’s planning to consider.

An 1876 map of New Westminster and the Lower Mainland, showing Sumas Lake before it was drained for agricultural land
This historic map shows Sumas Lake, in the lower right, before it was drained in 1924 to make way for farming and colonial settlement. Map: Forbes G. Vernon / City of Vancouver Archives

The research sparks challenging questions about “managed retreat,” which refers to purposefully relocating people to a safer area. As drought, floods and wildfires threaten the places we call home, more difficult conversations will need to be had about what the financial, social, cultural and ecological costs come with every decision, and who gets to decide.

As people in British Columbia brace for another destructive wildfire season, following droughts that persisted throughout the winter as lingering wildfires smoldered under the snow, the intense rains of 2021 may feel far out of mind. But whether it’s floods or wildfires, the research taps into the collective anxiety and uncertainty many people living on the coast are grappling with, and raises uncomfortable questions that are difficult to answer. When disaster strikes, what must be saved or abandoned? What would it take for me to decide to leave this place I call home — or what could force me to leave? 

A difficult decision ahead for Sumas Prairie

“I have friends and relatives who live on Sumas Prairie, very good friends that I have grown up with that are farmers,” Chief Dalton Silver said. The Semá:th had their food source taken away from them when the lake was converted to agricultural land — they are not looking to put anyone else through a similar experience, he said.

Dalton Silver, chief of Sumas First Nation, speaks at a news conference, flanked by several others. They all wear hard hats and high-vis vests
Sumas First Nation Chief Dalton Silver would like to see the restoration of Sumas Lake — but not against the will of the area’s current residents and farmers. Photo: Province of British Columbia / Flickr

“People point out that food security is something that’s in mind, with the richness of farmland underneath [the lake]. Initially, it was food security for our people. Now, on the other hand, with the lake gone and the farmland that’s there, that provides food security for a great number of people.”

He said that in researching flooding part of the lake, “our idea is not to kick people out of their home.” They are looking towards a situation where people would be willing sellers — which he acknowledged would be a “long, hard process.” And for some, the challenge is not just leaving their homes, but about reconciling a deeper difference in worldview.

“Some people find it a lot easier to throw their support around the idea of some built infrastructure versus letting the water come in,” he said. But on the other hand, “It’s not our way as Semá:th people to be fighting nature.”

City of Abbotsford says focus remains on flood prevention, not managed retreat

The 2021 B.C. floods caused over 3,000 people to evacuate from Abbotsford, B.C.. In early November, an atmospheric river brought extreme rains to the West Coast, flooding waterways, killing over 670,000 livestock and causing millions in damages. In late May, the Supreme Court certified a class action lawsuit alleging the City of Abbotsford was liable to pay damages due to it not closing the floodgates at the Barrowtown Pump Station in time. The allegations have not been proven in court. 

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The new report, coauthored by University of British Columbia researchers, non-governmental organizations and Semá:th First Nation, concludes that since 2021, flood response has been “a continuation of the status quo” to build up concrete, and that more innovative thinking is needed. 

The team analyzed four flood response options proposed by the City of Abbotsford (developed by an external contractor). The proposals range from $200 million to $2.4 billion, with the two cheaper options including status flood mitigation with some enhancements, and the two more expensive options include adding a floodway and wider enhancements.

They looked at B.C. land assessments and concluded it would cost approximately $956 million to buy back a portion of the lake-bed — which would be cheaper than the two more expensive options the city put forward. They acknowledged there would be further costs beyond buying up land — additional flood infrastructure may still be required, as well as cleanup and decontamination. But the authors emphasized that even if costs of their scenario doubled, it would still be less than the two more expansive and expensive options put forward by the city.

The City of Abbotsford emphasized the economic benefits of agricultural land in its statements to The Narwhal and other media outlets.

“Our farm economy is also responsible for $3.83 billion in economic activity each year and supports 16,770 local jobs,” the City of Abbotsford’s communications manager, Aletta Vanderheyden, told The Narwhal in a statement. Vanderheyden said about 50 per cent of all dairy, chicken, turkeys and eggs consumed in B.C. come from Abbotsford, with a large majority of food production in Sumas Prairie.

“Reflooding Semá:th Xhotsa would mean losing that premium agriculture land and would significantly impact our provincial food supply,” Vanderheyden said.

“As a municipality, our responsibility is to ensure that our community infrastructure protects our community and residents,” Vanderheyden continued. “This is our legislated responsibility under the Local Government Act and Community Charter — which is why we are looking at flood protection measures versus re-flooding options. Re-flooding would be an entirely different direction and one that would involve all governments. Our focus remains on flood protection.”

A historic pamphlet, titled Sumas Reclaimed Lands, with an illustration of farms filling a valley bordered by mountains. There is also a Province of B.C. crest
This B.C. government pamphlet advertised the sale of agricultural land after it drained Sumas Lake. Image: Province of British Columbia / Frontiers in Conservation Science

Riley Finn, lead author of the paper, said there’s different ideas of progress, or even what qualifies as infrastructure. He points out land was bought up for the Site C dam to be flooded by the reservoir, but it isn’t viewed as “regressive” since infrastructure is being built.

“If we were to buy out properties in the lake that would be viewed as regressive, perhaps by some, and maybe that’s because the lake isn’t viewed as infrastructure in the same way that heavily engineered infrastructure might be,” he said. “But that’s the principle behind green infrastructure, or working with nature to decrease the burdens that we put on ourselves through these heavily engineered solutions.”

Finn, who works as a researcher at the Martin Conservation Decisions Lab at the University of British Columbia, pointed out some costs, like biodiversity loss, are much harder to quantify monetarily but are no less valuable. Still, he emphasized that the research study is not a complete accounting of the costs and benefits to either the retreat or concrete infrastructure options. The idea was to put reclaiming part of the lake “on equal footing” as concrete infrastructure options. 

“There’s going to be significant costs in either what path we take,” he emphasized.

With peoples homes at risk, ‘transformational thinking’ is needed

Many people are feeling climate anxiety about how their health and homes could be impacted by climate change. Tara Martin, co-author of the paper and professor at the University of British Columbia’s department of forest and conservation sciences, said the public’s worry is exactly why broader solutions and “transformational thinking” are needed.

“What we’re finding is that the actions that we’ve taken in the past to deal with catastrophic events are not necessarily the actions we need to take in the future. In fact, a lot of the actions that we’ve taken in the past have made things worse,” she said.

Heavy equipment works to repair a section of road, which sits next to and barely higher than a flooded waterway
The costs of maintaining flood protection infrastructure in the Sumas Valley are enormous, particularly as climate change increases the frequency and severity of storms and floods. Photo: B.C. Ministry of Transportation and Infrastructure / ​​Flickr

“The floods are coming and the fires are coming. What we need is to minimize the risk to people, to infrastructure and to wildlife,” she said.

After doing something a certain way for a while, we become resistant to change, she said. But managed retreat can offer families and businesses an alternative — “potentially a lifeline.” Martin said many Sumas Prairie residences are uninsurable since the 2021 floods.

But she acknowledged that these factors don’t make it an easy decision.

“It’s people’s homes, it’s their livelihoods. It’s not a trivial thing to ask people to move somewhere else.”

‘Harmonizing with the water’ offers a way forward 

Murray Ned, who works as an advisor to the Semá:th Nation and executive director of the Lower Fraser Fisheries Alliance, said for a long time, provincial and federal governments have been willing to trade-off ecosystems for economic benefit — as when the lake was first drained in 1924 because it was a “nuisance” for settlers that flooded regularly and brought mosquitos. Ned, who also coauthored the study, said recognizing First Nations rights and valuing ecosystems is necessary going forward adapting to climate change and managed retreat.

He said in planning for the future, people need to be “harmonizing with the water” instead of fighting it.

“This is really about the entire province of B.C. and the impacts in our Stó:lō territory,” he said. “We’re also having these drought years. We’re expecting a fairly dry summer … so fish need to be able to migrate in these conditions with low water and higher water temperatures. This is not just about this territory, but rather the entire Lower Fraser and how to best manage that as a partner with the province, the feds and local stakeholders.”

People and communities will assign different values to loss of livelihood, habitat or food sources, whether monetary or intrinsic value. Likewise, the resiliency of an ecosystem, a food network or a local economy all have high stakes across communities. Abbotsford emphasized the economic benefit of agricultural land. Martin described the cost of natural disasters, like the 2021 floods, which were not considered in Abbotsford’s calculations for its four flood response options. Finn emphasized the benefits of salmon restoration and climate change mitigation, while Ned emphasized the value of retaining water during drought. Silver brought up the value of supporting other species that once relied on the lake. 

A composite black-and-white panorama of Sumas Lake, take prior to 1922
When Semá:th Xhotsa (Sumas Lake) was drained, it took away a important food source for Semá:th People. Now, the City of Abbotsford cites the region’s agricultural production as a reason it isn’t contemplating reflooding parts of the lake. Photo: Leonard Frank / Vancouver Public Library

The increase in natural disasters in recent years is only one part of a wider story of watching ecosystems and ways of life be destroyed, Silver said. 

“The destruction of our homelands we’ve seen over the last 150 to 200 years, it seems like it happened so quickly,” he said. “The lake was of huge importance to us.” 

But through radical environmental and social change, “our people adapted,” he said, which is key to overcoming the greater challenges ahead. To adapt to climate change, “it would be a lot easier if people would open their minds more to trying to live with nature and work with nature rather than the mass destruction that’s happening.”

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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