The first components of the Pennsylvania Turnpike’s Advanced Traveler Information System (ATIS) are up and running in southeastern Pennsylvania and work has begun on the $3.5 million second phase of the project.

Phase I of the ATIS consists of a network of highway advisory radio (HAR) stations and variable message signs (VMS) which are controlled from the Turnpike’s Operations Center in Harrisburg. The system allows for coordinated distribution of construction, accident, and traffic information to travelers while they are driving on the Pennsylvania Turnpike.
HAR stations are currently broadcasting at AM 1640 from transmitters located at the Downingtown Interchange, the Valley Forge Service Plaza, and from the Mid-County and Willow Grove Interchanges on the Turnpike’s mainline and at the Lansdale Interchange on the Northeastern Extension.

VMS units are operating in the eastbound lane in advance of the Valley Forge Interchange, westbound in advance of the Mid-County Interchange and southbound on the Northeastern Extension between the Lansdale Interchange and the junction with the Turnpike’s mainline.

Southeastern Pennsylvania was chosen as the first region where ATIS would be developed so the system could be utilized to help control traffic during the $40 million Schuylkill Rive Bridge/Diamond Run Viaduct rehabilitation project which is now underway.

"The Turnpike’s new system of highway advisory radio stations and variable message signs provides us with a powerful new tool in communicating traffic, construction and weather-related information to travelers," said Turnpike Executive Director John T. Durbin. "It is timely to have the system operating in southeastern Pennsylvania, where high traffic volumes and construction activities have made instant communications with drivers a necessity."

According to Steve Barber, the Turnpike’s Director of Safety and Operations, the second phase of the program involves the construction of four more VMS units, eleven additional HAR stations, and the installation of two closed circuit television systems to monitor traffic flow at the Valley Forge and Mid-County Interchanges.

The VMS and HAR units will enhance the system in southeastern Pennsylvania and expand ATIS westward into the Pittsburgh area. Permanent variable message signs will be built at milepost 309 eastbound near the Downingtown Interchange, at milepost 143 eastbound near the Bedford Interchange in central Pennsylvania, at milepost 60 westbound near the Pittsburgh Interchange, and at milepost 46 near the Allegheny Valley Interchange in western Pennsylvania.

Nine of the eleven new highway advisory radio units will be placed at Turnpike interchanges on the mainline including Cranberry, Pittsburgh, New Stanton, Bedford, Breezewood, Carlisle, Harrisburg-West, Morgantown and Philadelphia. A unit will also be placed at the Pocono Interchange on the Northeastern Extension.

One of the HAR units will be located off the Turnpike at the intersection of I-76 and I-476. "That unit will work in conjunction with transmitters at the Mid-County Interchange and the Valley Forge Service Plaza to provide better coverage in that area," explained Barber.

Barber said construction is now getting underway on Phase II projects, and design work has begun for projects to be built under Phase III of the program. Phase III, to be constructed at a cost of $7.5 million, will enter the construction phase in the fall of 1999. Phase III will see the installation of four more permanent variable message signs, five additional highway advisory radio units, and seven more closed circuit television systems.

The system will also include closed circuit television cameras to monitor traffic flow at key interchanges, a traffic flow detection system, a roadway weather information system, a truck rollover alert system and an over height detection system.

The final phase of the ATIS program will also involve the installation of four roadway weather information systems. The weather stations are tentatively slated for construction on Laurel Hill in Westmoreland County, a site between the Somerset Interchange and the Allegheny Tunnel, and on Sideling Hill. A station will also be placed on the Northeastern Extension north of the Mahoning Valley Interchange. "These weather stations will provide us will real time roadway conditions," Barber explained. "This will allow, for example, the rapid deployment of snow removal and salt crews."

A traffic flow detection system will be installed in southeastern Pennsylvania between the Valley Forge Interchange and the Delaware River Bridge, and north on the Northeastern Extension to the Lansdale Interchange. "Speed, flow and volume detection sites will indicate when there is a slowing of traffic and will alert the operations center to any developing back-up," said Barber.

Two truck warning systems will also be build as part of Phase III of the ATIS project. An over height detection system will be installed on the Northeastern Extension on the northbound lane just south of the Lehigh Valley Interchange to allow oversized trucks to exit the Turnpike before encountering the Lehigh Tunnel.

Truck rollover systems will be placed at the Breezewood and Carlisle Interchanges. "Speed, weight and motion detectors will combine to activate a warning if trucks attempt to exit the Turnpike at a speed sufficient enough to cause a rollover," said Barber.

When completed, over $13 million will be invested in constructing the Pennsylvania Turnpike’s Advanced Traveler Information System. "Once again the Pennsylvania Turnpike is on the cutting edge of using new technology to enhance safety and to improve travelling conditions," Durbin concluded.

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