Traffic congestion will increase in the USA

Harvard Center for Risk Analysis : scientists
Traffic congestion will increase by more than 30% in 18 U.S. cities by 2030. The biggest increase (54%) will be in Raleigh, North Carolina.
Models for studying the range of trends and impacts — from urban growth to regional migration to the replacement of gas guzzlers with clean hybrids — are becoming increasingly sophisticated, thus giving policy planners in public health and transportation a great chance to invest the necessary resources for improving the quality of transportation.

Harvard Center for Risk Analysis (HCRA) at the School of Public Health, cited by The American Road & Transportation Builders Association, [online] Available: