Highways in Canada

[thewave46]

Originally Posted by ScreamingViking

They were, but what used to be a "100-year flood" or "100-year storm" is both more frequent and more severe.

Other factors will also have to be considered: changes in freeze-thaw cycles, increased summer vs. winter temperature extremes, changes in the predominant types of precipitation by season (more or less snow, rain, ice).

Design standards have to be updated to reflect all this, and they'll vary by region of the country. But that just means new infrastructure will be built to withstand expected future weather events, climate norms, and environmental risks. Upgrading the older stuff will either happen when it's due for replacement, or if it's deemed important enough and at a high enough risk that it needs to be done before its useful lifespan is up.

While true, I'm not sure a '100-year' concept is really well-developed in much of Canada or extremes tested with any rigour.

A lot of this country has only had permanent settlements for ~100-150 years. I'd imagine that any realistic flood mapping has only existed for the last 75. Before, it was probably 'Don't build on the swamp' and hope for the best.

When the first all-terrain highway was completed across this country in, uh, 1943, it doesn't exactly lend itself to in-depth analysis of extreme events and their effect on modern infrastructure.