Traffic is inevitable — but not all congestion is bad. Retailers thrive on bustling streets, and, up to a point, the more people and goods moving through a neighborhood, city or region, the healthier its economy.
Once a threshold is reached, however, the cost of adding another vehicle to the road — in terms of delay and other drawbacks of traffic — outweighs the benefits to society.
This tipping point is different for every roadway. The research team behind this report determined the efficient level of traffic for different expressways and arterial roads in metropolitan Chicago, then measured the cost of additional traffic. What they found is excess congestion has infected our entire region’s transportation network — and the costs are far greater than anyone has previously estimated.
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