Modifying your original route while driving: not always a good idea

In: Blog, Nodum news, Road ecology, Safety, Smart Mobility, Traffic management

We all continuously check our GPS to find the quickest routes to our destinations, but can we be sure we actually take the fastest ones? 

Last Christmas, I had to drive from Washington DC to JFK Airport in New York City: My phone estimated 4 hours and 38 minutes at the time of departure through highway I-95. It was peak time in the Christmas season, so I planned and left in advance as I expected more delays than usual. As I moved forward through my route, I started to get some traffic due to accidents and some construction operations on the highway, adding 47 more minutes to my trip. I finally listened to my phone and I took the proposed detour via local roads that would save me some time. What initially seemed to be a good idea, turned to be a never-ending driving seeming experience.

Apparently, everyone took the same detour that I did, so the local roads ended up having heavier traffic than the I-95 route. When I finally arrived at JFK, it took me 5 hours and 42 minutes, 64 minutes extra instead of the original 47-minute delay if proceeded through I-95.

How could this be prevented? It looks like the number of vehicles that chose that alternate route highly exceeded its capacity, generating bigger congestion than the original one in I-95. Longer travel times are more susceptible to changes, as several factors can modify the original time estimation. Nevertheless, this case can be studied from a traffic management point of view to extract conclusions.

Do regular mapping software actually provide the fastest detour?

In general terms, regular mapping software used nowadays comes up with the fastest possible detour at the time the vehicle faces an obstacle. Indeed, the user will always be driving in the quickest path to arrive at his destination, but this path may not be the most suitable one to be proposed as a solution to traffic congestion. Is that detour ready to face the traffic created by hundreds of new vehicles? Will this bypass originate future traffic congestion to adjacent roads? How will this new traffic impact surrounding neighborhoods? Alternate routes shouldn’t be selected as provisional solutions to a problem, they should instead be studied in advance.

Nodum solves this and other problems by applying a different concept to traffic management. All possible detours are previously studied by engineers to guarantee a continuous traffic flux. If the detoured vehicles have a possibility to originate new traffic congestion, this alternative will not be selected by Nodum and a new one will, therefore, be evaluated.

This concept is highly emphasized in roadways under construction with live traffic, where accidents or production activities can generate a higher impact on traffic. The general contractor can use this software to choose which detour will be most efficient in case of a roadway closure, making sure they have enough capacity.

Two statements can be deducted if Nodum was used in my JFK trip: First, its duration would have been surely shorter; and second, all neighbors that were affected by all the hundreds of vehicles blocking their local roads would have experienced a way more peaceful day.