This report provides real-world experiences of using intelligent transportation systems (ITS) in work zones in four locations across the U.S.:
- Springfield, IL I-55
- Lansing, MI I-496
- Albuquerque, NM I-40/I-25
- West Memphis, AR I-40
The ITS applications in work zones were used to provide traffic monitoring and management, and traveler information. The primary purpose of the ITS for the Albuquerque project was incident management. Each of the work zone systems provided real-time information on dynamic message signs (DMSs). Real-time work zone information was also provided on the Internet with the exception of the Arkansas system. The ITS were automated with two traffic management centers being staffed during early morning to evening. Most systems were temporary; however, the Albuquerque system was to become part of the permanent freeway management system after the construction project was completed.
The Illinois DOT (IDOT) used ITS in a 40-mile work zone on I-55. The Real-Time Traffic Control System (RTTCS) consisted of 17 remotely-controlled portable DMSs connected to a base station server via wireless communication, eight portable traffic sensors connected to the server via wireline, and four portable cameras linked to the base station server via wireless communication. IDOT leased the system for the duration of the reconstruction project. The lease included a provision for contractor personnel to monitor the system. The system operated in an automatic mode; however, one person was assigned to check system performance periodically during week days. After hours and during weekends, contractor personnel were on-call to handle problems.
Specific costs for the RTTCS were not available for this publication; however, the system cost was provided in a later publication. Access the system cost summary.
The Michigan DOT (MDOT) used a Temporary Traffic Management System (TTMS) during a construction project in downtown Lansing. The system was deployed from March 2001 to October 2001 and removed at the completion of the construction project. The project involved a complete closure of portions of I-496. The $40 million construction project included the rebuilding of 32 bridges, reconstructing one mile and repairing seven miles of freeway, and adding a third lane/merge weave in each direction for a section of the freeway. The TTMS was used throughout the construction project. The system included 17 cameras, 12 DMSs, six queue detectors (microwave sensors), and a commercial off-the-shelf (COTS) software package which ran on a server located at the Construction Traffic Management Center (CTMC). Based on data from the detectors, appropriate messages from a bank of predefined messages would be displayed on each DMS and on the Internet. Operators had the option of manually updating the messages.
MDOT purchased some of the hardware components of the work zone system (e.g., communications tower, antenna, queue detectors, and cameras) and software license, but most of the system was leased. The cost of the lease was $2.4 million which is about 6% of the total project cost.
The New Mexico State Highway and Transportation Department (NMSHTD) used ITS in a 2-year construction project of “The Big I” interchange where I-40 and I-25 intersect. The primary purpose of employing ITS was to aid in incident management and response. The 2-year project began June 30, 2000 and involved construction of 111 lane-miles, 45 new bridges, and 10 rehabilitated bridges. The ITS included eight fixed CCTV cameras, eight modular (expandable) DMSs, four arrow dynamic signs, four portable DMSs, four portable traffic management systems (a single integrated platform for camera and DMS), and four highway advisory radio (HAR) units. Components were linked to base station computers via wireline and wireless communications. Camera images were monitored at the traffic management center by NMSHTD staff from 5:00 am to 8:00 pm. Information on traffic conditions were provided via the HAR and DMS, and via other outlets to include website, radio, fax and email distribution lists. Although pre-defined messages could be activated automatically, the system was set for manual initiation.
NMSHTD purchased the ITS with the intent of incorporating much of the system into a freeway management system once construction was completed. Other components would be used in future work zone projects. The ITS work zone system cost $1.5 million.
West Memphis, AR
The Arkansas State Highway and Transportation Department (AHTD) employed an ITS for a 3-mile concrete reconstruction project in West Memphis on I-40 near the intersection with I-55. The work zone was near a bridge across the Mississippi River from Memphis, Tennessee and abutted a Tennessee work zone on the bridge. The reconstruction project was expected to last 12 to 18 months and cost $13.8 million. The work zone was expected to be in place for the duration of the construction project.
The Automated Work Zone Information System (AWIS) included 12 queue detectors and five remotely controlled DMS which were linked to a central base station server via wireless communications, three HAR units, five pagers, and an email alert system. The traffic detectors were installed one mile on each side of the work zone. The DMSs were deployed over approximately 9 miles on each side of the work zone. The HARs range was approximately 23 miles. The server processed data from the queue detectors and disseminated messages to the DMS and HAR based on predefined messages for specific traffic conditions. AHTD and Tennessee DOT staff, contractors for both work zones, traffic reporters and other media were informed of traffic conditions via email and pager alert systems.
The AWIS was leased for the duration of the work zone project. The lease included personnel to monitor the system. Usually one person was required for periodic system maintenance and to be on-call after hours. The terms of the lease called for a daily fee paid to the contractor and a lump sum for the HARs. The fee was assessed each day the system was operational, thereby the state did not pay for any system down time. The total cost of the AWIS was $495,000 which included the daily fee and purchase of three HARs. The AWIS cost was less than 4% of the total reconstruction cost.
Intelligent Transportation Systems in Work Zones: A Cross Cutting Study - Integrated Work Zone Systems for Improving Travel Conditions and Safety
Lansing, MI: $2.4 million (lease). Albuquerque, NM: $1.5 million. West Memphis, AR: $495,000 (lease).