This research was a "scan team" effort jointly sponsored by the Federal Highway Administration (FHWA), the American Association of State Highway and Transportation Officials (AASHTO), and the Transportation Research Board (TRB). During a two-week period in May 1998, the team visited with transportation officials in Gothenburg, Sweden; Frankfurt, Cologne, and Bonn, Germany; Paris, France; and London and Birmingham, England to identify noteworthy practices and technologies that may have value in the United States.
Several European cities operate real-time parking information systems. Primarily these systems are utilized in downtown areas. They usually consist of a set of detectors to count the number of vehicles entering or exiting garages or lots. Display of available parking can then be transferred to variable message signs informing drivers of availability of parking. Benefits have shown a reduction of up to 25 percent in downtown traffic volumes related to searching for parking spaces. These timely messages have also shown enhanced use of transit and improved use of park-and-ride lots serving transit when drivers are informed that parking is full.