Urban planners and traffic engineers have many strategies for traffic calming, including narrowed roads and speed humps. Such measures are common in Australia and Europe (especially Northern Europe), but less so in North America, where the focus is often more on facilitating motorized traffic flow.
By “lane narrowing” I meant reducing the width of the lane (e.g. from 12’ to 11’ or even 10’). Road diets (going from 4 lanes to 2 or 3) are a separate issue, although they can have traffic calming effects.
Also illegal in this state, you can’t just change the width of lanes…
Meanwhile I’ve never heard of speed bumps being implemented on a street wider than two lanes, so it sounds like your state’s DOT has some policy updating to do.
I am actually referring to back around 2012, when the DOT plus the IAB got a clue and started growing a few braincells…