According to some sources, Los Angeles is the most congested city in the world, followed by New York and Moscow. Angelenos spend an average of 102 hours in traffic jams during peak hours, costing each driver $2,828 a year and the city $19.2 billion from direct costs (eg, fuel and time wasted) and indirect costs (eg, freight and business fees from company vehicles idling in traffic). These fees are passed on to you and me.
What’s frustrating in Los Angeles is policymakers’ inability to do anything about the problem. In the past, the answer has been to add lanes to freeways, but this is not a permanent solution and actually adds to further congestion and pollution. In New York, the city of the Yellow Cab, Uber and Lyft are also contributing to the increasing gridlock.
A group of researchers from Italy and the United States are trying to find a solution. Based in Rome, The National Research Council (Il Consiglio Nazionale delle Ricerche or Cnr) is the largest research institute in Italy; it conducts studies on demographic and migration issues, among other things. It teamed up with researchers from MIT’s Senseable City Lab and Cornell University. They selected NYC as the first to study. The team tracked all Manhattan taxi rides for a year. Every single taxi trip was “tagged” with the times and the GPS coordinates of departure and arrival. They then developed an algorithm to calculate the sequence of routes that could be served by a single vehicle.
The results: By optimizing routes, NYC could eliminate almost half its current fleet of taxis. The routes would not have to be shared and the result would be almost optimal service levels. This is the result of organization, of an operation that could be performed with a smartphone app.
According to Paolo Santi, a researcher at Cnr and MIT and the team’s leader, “Taxi systems today are self-managed by the taxi driver himself, everyone has his own strategy, and there is no centralized system. Taxi drivers tend to concentrate in some more populated areas, neglecting others, creating an excess in certain areas and a lack in others.” The key to organizing them lies in the distribution of routes in such a way that each vehicle makes the shortest possible route without a passenger. According to Carlo Ratti, director of MIT’s Senseable City Lab, “If we take Manhattan as a whole, we could theoretically satisfy demand for mobility with 140,000 cars, about half of those circulating now. This means that the problem of tomorrow’s mobility cannot be tackled with more infrastructures, but with more intelligence: in other words, with more silicon and less cement.”
Can the study be replicated in other cities in the world, like Rome and Milan? Santi continues, “We have a considerable amount of data from many cities in the world but not from Italian cities. In Europe there is much more fragmentation and very restrictive privacy rules that make it difficult to test these models. We chose New York where data is accessed through only one authority.” But scientists are optimistic that they can expect to see similar reductions in terms of efficiency in European cities.
The landscape of city mobility is continuing to change with on-demand and transport-sharing services and with self-driving cars beginning to take hold. Computerized management of movement will prove to be fundamental. One day there could be an algorithm to direct traffic. Santi points out, “we analyzed the taxi system, but our approach applies equally to Uber and Lyft and in the future to self-driving cars. Thanks to these studies we will be able to properly size the fleets.” And there will be less demand for cars, decongesting the traffic and limiting the emissions of greenhouse gases and pollutants.