Vancouver Considers Abandoning Parts of the Coast Because of Climate Change

The city’s new report on sea level rise looks at many options to protect coastal areas from flooding. For the first time, moving people away from the coast altogether is one of them.

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Nov 4 2016, 3:42pm

Image: JamesZ_Flickr/Flickr

Vancouver prides itself on being a coastal city, nestled between the Rocky Mountains and the Pacific. Like every other part of the world, it's under threat from climate change, as warming temperatures cause sea levels to creep ever-higher. The city is looking at many options to hold back the rising water—and for the first time, retreat from the coast is one of them.

This week, Vancouver officials put out a report laying out plenty of options to deal with sea level rise, including barriers, dykes, and seawalls. But it also suggests that, at least in some parts of the city, they may want to consider just getting people out of the way. The option of retreat from the coast is on the table in Vancouver, and other cities might soon follow.

An illustration of the three strategies examined in the report, titled City of Vancouver Coastal Flood Risk Assessment Phase II: Final Report

Around the world, coastal cities are making tough decisions about how to best protect their populations from the inevitable increase in flooding. New York City, for example, has committed billions to climate change adaptation efforts, including seawalls and flood barriers.

But the option of retreat has rarely been seriously considered by officials, in Vancouver or elsewhere, due to its tricky politics. Having people leave their homes, sometimes decades before an actual flood occurs, is an unpopular ask to say the least.

According to the report, retreat in Vancouver would involve the city buying up residences and other property and 're-naturalizing' them. This means essentially allowing them to flood, in order to protect other areas. Of course, many residents of the city—where the average price of a detached home is well over $1 million—may not be eager to up and move.

"We need to have this conversation. Climate change is already in motion"

Doug Smith, who is Vancouver's director of sustainability, said that while retreating from sea level rise is "really a last case or worst case scenario," it was important to present all available options as the city decides how to tackle the problem.

"It's on the table, and I think just from a due diligence perspective we need to have that honest conversation with people," he said.

The report works with the provincial forecast of 1 meter of sea level rise by 2100, dividing the city into 11 zones based on flood vulnerability, and includes the economic, environmental, and social costs for a range of options that include to protect, adapt, or retreat, in each area.

For example, in the Southlands, a coastal residential area, the report suggests that full protection from flooding could be achieved via a 6.5km dyke, at a cost of $90-135 million dollars.

If retreat is pursued instead, the city would buy homes and businesses as they become available over the next 40-60 years, followed by more aggressive buyouts afterwards. Roads and infrastructure would be removed as the area is "aggressively re-naturalized" in 2070.

The plan would see 2,100 people bought out, and nearly four square kilometers of urban land turned into tidal plain, the report says.

Read More: Some Cities Are Falling Behind in Preparing For the Effects of Climate Change

It sounds like an extreme response, but the Vancouver area is extremely vulnerable to flooding. The report notes that by 2100, 13 square kilometers of city land, with homes and buildings totalling an estimated value of $7 billion dollars, will be on floodplains, and that without any actions taken now, a major flood event under projected conditions would displace over 4,000 households, and create enough debris to fill 4,500 dump trucks. It would be an unprecedented disaster for the city, causing billions in damage.

"We need to have this conversation," said Smith. "[Climate change is] going to happen, it's already in motion," as is sea level rise, he acknowledged. "There are things we can do to reduce the damage."

Jericho Beach, Vancouver. Image: kcxd/Flickr

The next step for Vancouver is to put its plans to the public via a series of outreach initiatives. While the timelines for some of the options stretch out towards the end of the century, many decisions will have to be made soon. Areas like Jericho Beach and the Fraser River are already experiencing more frequent flooding, and the city is planning to start projects there within the next year, according to Smith.

Whether those projects include retreat depends largely on how the public reacts. But the fact that residents will be asked to consider it is a good thing, according to disaster risk management expert Klaus Jacob, a geophysicist at Columbia University who has advocated for retreat to be included in New York City's sea level rise plans for years. Jacob has criticised what he sees as short-term thinking that assumes we can build walls against sea level rise when we don't even know exactly how much rise will occur, and thinks that retreat should be serious part of the policy discussion.

"There has to be a discussion. We will probably not retreat from southern Manhattan. But there are areas where it makes sense. Currently though, it's just not on the table," he said.

In Vancouver, the option of retreat is being taken seriously. And the decisions made there in the next few years are sure to be closely watched as other cities around the world make their own plans to deal with the rising seas.

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