Just posting abut a Saskatoon road situation that has annoyed/confused me for many years.
Heading north on Idylwyld, the speed limit increases from 50 km/h to 80 km/h as one approaches the underpass beneath Circle Drive. The speed increase happens after the off ramp to Circle Drive
Shortly after passing under Circle Drive, and before the on ramp from Circle merges with Idylwyld, the speed limit increases to 90 km/h.
Why is this? There is no change in road conditions whatsoever between the 80 km/h speed limit location and the 90 km/h speed limit location. The only possible explanation I can think of is that, in case of flooding of the underpass, northbound traffic would enter the flood water 10 km/h slower than if the speed limit immediately increased from 50 km/h to 80 km/h.
Any explanation from someone here? Is there a traffic design convention that you can't increase the speed limit by more than 30 km/h in one step? Help me, I'm confused.