The NJ Turnpike Interchange 6 to 9 Widening Program was a significant infrastructure project aimed at addressing the increasing traffic congestion on a critical stretch of the New Jersey Turnpike. The idea for this project was conceived in response to the steady rise in traffic volume and the anticipated growth in population and employment in central New Jersey. By 2032, northbound traffic volume was expected to increase by nearly 68%, and southbound traffic was forecasted to increase by 92%.
The project officially began in 2009, with the goal of widening approximately 35 miles of the Turnpike from Interchange 6 in Mansfield Township, Burlington County, to just south of Interchange 9 in East Brunswick Township, Middlesex County. The mainline was to be expanded from six lanes to twelve lanes from a point approximately two miles south of Interchange 6 to the existing ten-lane dual-dual roadway south of Interchange 8A. This required adding a new three-lane roadway in each direction for a 25-mile section of the Turnpike. Additionally, a third lane was added to the “cars/trucks/buses” lanes (outer roadways) of the ten-lane dual-dual roadway between Interchanges 8A and 9.
The project was one of the largest ongoing roadway projects in the Western Hemisphere at its peak, employing around 1,000 workers daily. The construction involved significant resources, including 140,000 cubic yards of concrete, 2.4 million tons of asphalt, 123 miles of guardrail, four miles of noise barriers, 17 miles of relocated pipeline, and 140 new over-the-road signs. More than 120,000 new trees were planted in the Turnpike right of way or on public lands in towns along the widening corridor.
The total cost of the project was approximately $2.5 billion. Despite its massive scale, the project was completed on schedule and more than $200 million under budget. The northbound lanes opened on October 27, 2014, and the southbound lanes opened on November 3, 2014.
Before the widening, the Turnpike experienced frequent congestion, particularly during peak travel times. Traffic studies conducted as part of the project’s planning phase indicated that the existing roadway would not be able to accommodate the projected increase in traffic volume. The studies forecasted significant growth in traffic due to expansions at the Port of NY/NJ, growth at Newark Liberty International Airport, and regional employment and population growth.
“Despite its massive scale, the project was completed on schedule and more than $200 million under budget.”
After the completion of the widening program, the Turnpike’s capacity was effectively doubled on the 35-mile stretch between Interchanges 6 and 8A, and increased by one lane in each direction between Interchanges 8A and 9. This has significantly alleviated congestion and improved traffic flow. The improved roadway is expected to accommodate traffic needs through the year 2032.
Theories of induced demand suggest that increasing road capacity leads to more traffic, as the improved infrastructure encourages more people to drive, ultimately negating the benefits of the expansion. However, in the case of the NJ Turnpike Interchange 6 to 9 Widening Program, these theories did not fully apply. The primary reason is that the project was designed to address existing and forecasted traffic demands rather than creating new demand. The traffic studies conducted before the project indicated that the existing roadway would not be able to handle the projected increase in traffic volume due to regional growth and expansions at key transportation hubs.
Moreover, the project included measures to manage traffic flow and reduce congestion, such as adding lanes to the “cars/trucks/buses” lanes and implementing advanced traffic management systems. These measures helped to ensure that the additional capacity was used efficiently and did not lead to the rapid re-congestion often associated with induced demand.
Overall, the NJ Turnpike Interchange 6 to 9 Widening Program stands as a testament to effective large-scale infrastructure planning and execution, addressing both current and future transportation needs in New Jersey without falling prey to the pitfalls of induced demand.
Sources
- NJ Turnpike Interchange 6 to 9 Widening Program :
http://njturnpikewidening.com - New Jersey Turnpike Interchange 6-9 Widening Project.
https://www.yu-associates.com/projects/new-jersey-turnpike-interchange-6-9-widening-project/ - NJ Turnpike Authority’s 6 To 9 Widening Program. https://www.stokescg.com/works/6-to-9-widening-gallery/
- New Jersey Turnpike Interchange 6 to 9 Widening Program. http://www.njturnpikewidening.com/documents/Program%20Widening%20Presentation.pdf
- NEW JERSEY TURNPIKE AUTHORITY INTERCHANGE 6-9 WIDENING PROGRAM. http://www.njturnpikewidening.com/documents/00_TableOfContents.pdf
- INDUCED TRAFFIC AND INDUCED DEMAND – National Association of City ….
https://nacto.org/docs/usdg/induced_traffic_and_induced_demand_lee.pdf - Induced demand – Wikipedia.
https://en.wikipedia.org/wiki/Induced_demand - Latest travel data show why induced demand remains just a theory. https://www.washingtonpolicy.org/publications/detail/latest-travel-data-show-why-induced-demand-remains-just-a-theory
- What Is Induced Demand? | Planetizen Planopedia. https://www.planetizen.com/definition/induced-demand
- Induced Demand Definition & Examples – Quickonomics.
https://quickonomics.com/terms/induced-demand
