Interesting story I saw on social media first. It's a pilot project in Ontario to add alternating passing lanes to a couple of sections of highway, (2 + 1) less cost presumably than twinning while improving safety. Apparently they're common in parts of Europe. It would definitely improve the TCH in this province. Since twinning is almost as much of a pipe dream as a tunnel to Labrador this should be a viable option.
https://www.ctvnews.ca/northern-ontario/...n-north-americas-first-21-highway-pilot/
https://highway11pilot.ca/about-the-project/
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