The waters are steadily rising, and here on the coast, we need to take the long view if we hope to keep our children’s feet dry. Victoria has already been making plans to deal with the rise in sea levels, and a new study suggests the costs of protecting coastal areas will be dwarfed only by the costs of ignoring the warnings.
The University of Southampton study, led by economist Stephane Hallegatte of the World Bank, examined 136 of the world’s largest coastal cities, including Vancouver, and estimated that losses from flooding could reach $63 billion a year by 2050. And that’s the figure if the cities start adapting to climate change. If they sit on their hands, the annual bill could be more than $1 trillion.
The cost of taking protective action will also be steep; the study pegged it at $50 billion a year for all the 136 cities. The figures are predicated on a sea-level increase of 0.2 to 0.4 metres.
In Vancouver, which was listed in the top 20 most vulnerable cities, the changes are as obvious as the rising water level in the region’s low-lying areas. In the past hundred years, sea level in the city has risen 20 centimetres, and the rate of increase is getting faster.
The city has responded by adopting a climate-change-adaptation strategy, which includes a flood-risk assessment and flood-proofing policies.
“I think it’s another strong message about why that work is so urgent, but I don’t think there’s any stronger message than the floods that we saw in Calgary this past year, and in Toronto,” said Vancouver Coun. Andrea Reimer.
“You might be able to argue with a report. It’s very hard to argue with the weather, and the observed impacts of extreme weather.”
It’s harder to argue when you gaze across the flat lands of Richmond toward the dikes that aren’t high enough for what’s coming. Vancouver’s spur to action is obvious.
Victoria doesn’t face the same combination of low-level flood plains, population growth and sinking delta land, but the ocean is at our doorstep, too. Except for a few areas, most parts of Victoria have some reassuring rock between the houses and the sea, which gives us at least the illusion of safety.
The city estimates that sea level will rise 45 centimetres by 2050; the effects will be most apparent during winter high tides. Storms could increase in intensity and frequency by about 15 per cent, leading to more storm surges, where wind pushes high waves onto the shore.
By 2100, sea level could rise by almost one metre.
The city’s climate-adaptation review says that, of all the climate-change events, Victoria is most vulnerable to sea-level rise. Docks, sea walls and piers are likely to be damaged or blocked by flooding. Storm drains could backflow, leading to flooding. Storms could overflow the sewage system, flooding homes with sewage and forcing untreated sewage into the ocean. Our coastline will be eroded.
The review says the greatest risk to the city is stronger and more frequent storms, bringing storm surges and heavy rain that causes flooding. Such events could happen about once a year.
Although Victoria doesn’t face the mammoth problems that Vancouver does, the city and the Capital Regional District are working on plans to turn the research into action. The region’s sewage project is one major undertaking that will have to take these forecasts into account.
The year 2050 might seem a long way off, but planning can’t wait until the water is on our doorsteps. The Southampton study is a reminder of the heavy cost of inaction.
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