In 2004, the Federal Highway Administration (FHWA) implemented the Work Zone Safety and Mobility Rule to focus on improving work zone operations. State Departments of Transportation (DOTs) are always looking for tools and applications that can help improve mobility and safety by actively managing traffic through the work zone. ITS applications provide a number of tools that should be considered when looking at options for mitigating traffic impacts that occur during construction. In 2003 an assessment was performed to highlight benefits, lessons learned, and tips from five DOT sites that implemented ITS solutions for work zone traffic management.
The study analyzed data from five sites:
- District of Columbia
- North Carolina
These sites were selected because the construction project showed significant potential to have a measurable impact on traffic conditions, creating a situation where ITS applications could be used to reduce the impact. Each DOT developed a list of lessons learned for other DOTs to weigh when considering work zone traffic management.
In 2004, the North Carolina Department of Transportation (NCDOT) designed an ITS work zone solution on a rural section of I-40 west of Winston Salem. The goal of the system was to monitor traffic conditions and improve mobility and safety through the work zone. The work zone was about 4 miles long between the I-40/NC 801 interchange in Davie County and I-40/SR 1101 interchange in Forsyth County and also included a bridge rehabilitation project on I-40 about five miles east of the work zone. The majority of the construction was restricted to night work. NCDOT offers the following lessons when implementing ITS applications as an integral part of the work zone management plan.
- Link the schedule for ITS deployment to the construction schedule to maximize use and benefits of the system. The ITS system was deployed several weeks after the construction work zones were already set up and construction had begun. The most significant traffic impacts had occurred during this time, reducing the overall benefit the ITS applications had on the safety and mobility of traffic through the work zone. To achieve the maximum benefit of the ITS system, all applications should be operational prior to any lane restrictions.
- Involve the construction contractor in the design and implementation of ITS applications to the fullest extent possible. The construction contractor should be involved in the design and implementation of any and all ITS solutions being considered as part of the work zone management plan. Local NCDOT representatives cited the need to involve the construction contractor to the extent possible so they would be fully aware of the goals and objectives for the system.
These lessons provide insight into what practitioners can expect when deploying a similar ITS work zone solution. NCDOT suggests that in order to get the full benefit of an ITS solution implemented as part of the work zone, the contractor needs to be involved in the design and implementation of the applications and all ITS components need to be installed and operational at the beginning of the construction project. By adhering to these lessons, other practitioners will benefit from the experience of NCDOT, advancing their knowledge of ITS work zone deployments, and improving the safety and mobility of travelers through construction zones.