In 2003, the Federal Highway Administration (FHWA) began the Work Zone Mobility and Delay Reporting Assessment to document the tangible benefits of using ITS in work zones in a quantitative way. The purpose of the study was to highlight "before and after" analyses that quantify the mobility and safety benefits of using ITS applications for work zone traffic management. The study intended to increase the knowledge and promote further use of deploying ITS solutions for work zone 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 could be used to reduce the impact.
Arkansas Site Case Study
In 2000, the Arkansas Highway and Transportation Department (AHTD) began construction of more than 350 miles of roadway throughout the state. Construction included widening approximately 17 of these miles on I-30 from Little Rock to Benton. Seven projects comprised the I-30 work zone corridor and included interchange reconstruction, installing a concrete barrier wall in the median and converting all frontage roads to one-way. The complexity of the projects and extensive work zones lead the AHTD to install an Automated Work Zone Information System (AWIS) covering the entire I-30 Little Rock to Benton work zone corridor.
The objective of adding AWIS to these extensive work zones was to improve the safety and mobility of the travelers and to reduce crashes. The complete system of monitoring equipment included: Dynamic Message Signs (DMS), video cameras, detection sensors, Highway Advisory Radio (HAR), and a website that provided traffic speeds through the work zones. The main areas of evaluation for the work zone encompassed safety, mobility, and productivity as well as the impact on travelers and construction workers.
Driver surveys and traffic volume data were collected to assess the hypotheses that centered around improving the safety of travelers. Commercial vehicle drivers and private vehicle drivers participated in the surveys. Traffic and survey data were collected from May 17, 2004 through June 20, 2004. Crash data were also reviewed, but it was determined that it was not feasible to use the crash data because the crash records did not contain the level of detail necessary for the study.
- Of the drivers surveyed, 82 percent agreed that the AWIS improved their ability to react to slow or stopped traffic.
- Forty-nine percent of respondents agreed that they felt safer traveling through the work zone because of the electronic messages.
- Most drivers (79 percent) felt the DMS were accurate.
These results are also found in the document - Benefits of Using Intelligent Transportation Systems in Work Zones: A Summary Report, Federal Highway Administration, April 2008. http://ops.fhwa.dot.gov/wz/its/wz_its_benefits_summ/index.htm