The Interstates...
an overview. Some will know that Eisenhower was in large part responsible for the building of our current interstate system. The overall goal was to span the east to the west with roadways that would ...
Forum Discussion
Dog Folks wrote:
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One of the major problems with our interstates is that they are supposed to be a "limited access" system, and there are way too many exits and entrances.
I don't there is a clear distinction between too many and too few interchanges. The frequency of interchanges varies widely.
The Eisenhower through the west side of Chicago might have too many, with the complicating factor that some are left exits. But the Indiana tollway readily added exchanges in the South Bend/Elkhart area to handle the US20/31 bypass. Tollways in general have less than urban freeways.
On I5 north of Seattle they have added interchanges to accommodate traffic to malls that have been added since the freeway was built. They have also reworked interchanges to eliminate crossing traffic. In a number of cases exiting traffic mingled with entering traffic. In other cases exit lanes were too short, leading to backups on to the freeway.
Any freeway built through a rural area will need to be changed when suburbs grow up around it. Or consider I15 through Las Vegas. That was 64000 people in 1960, and nearly 10x that now. Adding lanes, adding interchanges, reworking interchanges to handle more traffic, are all part of raising the carrying capacity.
