Stephen Rees's blog

Georgia Strait

A team of three from Bing Thom architects what a two metre and a seven metre sea level rise looks like for Vancouver. Useful, but not nearly enough. How hard would it have been to do the region while they were at it? The low lying areas are, mostly, outside the City of Vancouver in the delta of the Fraser River – and quite a lot of the Fraser Valley too. This is something that I have worried about here more than once. At least the article does cover my concerns – to some extent

Richmond city council has already approved a flood-protection management strategy through to 2031. According to a 2009 report to council by the city’s director of engineering, John Irving, the city owns and operates 49 kilometres of dikes on Lulu Island.

“While there currently is not a Provincial sea level rise policy in place, the Province has indicated in recent correspondence that current construction around dikes should allow for future dike raising to address a 1.2 metre sea level rise by the year 2100,” Irving wrote.

Later in the report, he added: “Given the fact that sea level rise is taking place in the absence of a Provincial policy, staff have been proactively proceeding with dike upgrades since 2005 based on an allowance of 0.5-metre over and above the current Provincial requirement.”

The cost of doing this would be $28.2 million, according to Irving’s report, which noted that raising the dikes to address a sea-level rise of 1.2 metres would increase the cost.

There has also been some research at the regional level.  …

The federal and provincial governments published a document in December 2008 listing three scenarios for sea-level changes in B.C. The “extreme low” analysis estimated that the Fraser River Delta will see a 35-centimetre rise by the end of the century. The “mean” estimate was a 50-centimetre increase, and the “extreme high” prediction was for a 1.2-metre jump in sea level by 2100.

Now the interesting figures are those predictions. So why did the Bing Thom team go for much bigger sea level rises  than the governments?

Heeney, Keenan, and Yan recently visited the Georgia Straight office to talk about their work, which examined the impact of sea level rising in one-metre increments up to seven metres. Yan described their research as a “tool kit and an atlas for discussion”.

So the while the consensus used by governments here seems to be 1.5 metres by the end of the century, the tool kit at least allows Vancouver residents to see what might happen if that turns out to be a conservative estimate.

The trio from Bing Thom Architects said they’re not climate scientists, and their intention isn’t to provide all the answers. Instead, they hope that their maps tracking the impact of sea-level increases will lead to better planning decisions in the future. “This is to aid in the discussion so that people can see these implications,” Heeney said.

Well, I think we need to see those implications for the impact of salt water ingress on agricultural land behind the (raised) dykes. Also for the implications on the Gateway projects like port expansion and the SFPR – which runs along the shore of the South Arm.

The firm was able to conduct this research thanks to the city’s open-data catalogue, which makes information about the shoreline available on the city’s Web site.

So why is there no equivalent data set for the rest of the region – especially those areas which are clearly far more vulnerable?