When I was working as an environmental consultant, traffic studies relied on knowing how many cars passed by a particular location in each lane. For a better understanding, a breakdown of the types of vehicles during the various times of day would increase the accuracy of predictions. From this data alone, we could predict the effects of closures, additions, and detours.
In modern times, especially in places like the entrance to the George Washington Bridge, the data is easily accessible due to constant video monitoring. It is easily accessible without affecting traffic.
Patrick Thibodeau recently researched and wrote an article for "Computerworld" (A New Jersey 'traffic study') discussing these methods in compison to the "Traffic Study" done under Chris Christie's watch:
On busy roadways, though, engineers are likely to use camera video detection with software that can count vehicles. That's the least intrusive method, and the documents released last week suggest that such a video camera system in installed on the George Washington Bridge.
The ice supporting Chris Christie's presidential bid just got a bit thinner.
