Reducing traffic congestion in cities by delivering goods at night

By Logan Dredske

Shifting store, restaurant, and other business deliveries to nighttime hours could reduce traffic congestion within cities. A study conducted by the KTH Integrated Transport Research Lab (ITRL) in Stockholm, Sweden, has found that scheduling deliveries to businesses during off-peak (night) times can reduce congestion within a city. Large freight vehicles travelling through urban cores and parking on streets while unloading goods adds to traffic congestion. In addition, traffic congestion cost U.S. trucking companies $63.4 billion in 2015. However, Stockholm is a unique city because it bans truck deliveries between 10 p.m. and 6 a.m., intended to reduce noise in the city during the night.

ITRL launched their pilot program in Stockholm to compare the performance of freight vehicles completing night deliveries versus day deliveries. A portion of the program featured one truck delivering goods between 10 p.m. and 6 a.m., and three trucks delivering goods between 6 a.m. and 8 a.m. – all trucks transported goods between the same warehouse and stores. ITRL found that the truck delivering at night had at least 30 percent faster deliveries and 4 percent lower fuel consumption compared to the morning trucks. “That’s one truck doing the work of three, or in other words – morning commuters are spared having to share the road with three heavy duty trucks,” says Anna Pernestål Brenden, a researcher for the lab.

ITRL’s study also assessed whether deliveries at night bothered neighbors. The nighttime trucks used in the study had to follow rules such as not using reverse sounds and not talking on cell phones outside the vehicle. Part of the study also involved the testing of new technologies such as silent roller cages and electric hybrid trucks that automatically switch to electric powered engines in defined geographic areas. ITRL monitored noise via multiple microphones installed on the outside of the truck that were able to account for neighborhood background noise while recording truck and delivery noise. Researchers found that the main cause of noise was unloading the truck, not driving it. Responses regarding noise levels from neighbors in the study displayed a paradox: nighttime deliveries are acceptable in noisy areas, but deliveries in quiet neighborhoods require more training and technology to keep the noise down.

While it is not common for U.S. cities to have nighttime delivery bans, switching to off-peak delivery times could still prove beneficial. U.S. cities such as Chicago and New York have already been researching the benefits of off-peak deliveries.

Logan Dredske is a Project Assistant at SSTI.