There is a Field of Dreams quality to road expansion. Building more lanes on congested roads doesn’t mean that there will be any long-term reduction in traffic. As streets can handle more cars, more people will drive on them. This is a pretty basic fact, assuming no Detroit-style economic ruin.
So it looks like we’re narrowing Woodroffe Avenue in Hearts Desire. City planners don’t see any significant issue, as there are other routes that motorists can take to get through this slice of suburbia. So, is this just that same phenomenon in reverse? Will traffic levels adjust to match road capacity?
If increasing a road from two lanes to four lanes will increase the amount of traffic from X to Y (while maintaining traffic density), would reducing that road from four lanes to two lanes decrease the amount of traffic from Y to X? If not, why not?
And if it won’t, shouldn’t that make us even more cautious about road expansion?