Engineering and Construction

Transportation Technology

Intelligent Transportation Systems (ITS)

The ITS section provides support for ITS technology systems throughout Arizona. The team is comprised of an ITS/IT team that covers all technology and telecommunication support systems for ITS, and a Traffic Analysis section that specializes in recurring and nonrecurring congestion.

ITS/IT and Telecommunications

This section stays on the leading edge of technology, working with such ITS systems/items as a 350-port Video Switch, Statewide 511 Voice Response Activated (phone) System (VRAS), Statewide Traveler Information website with real-time GIS-based incident mapping, Statewide Departmental Radio Communications, multirecipient Paging System (for administrative notices of key incidents as well as maintenance response initiation), Dynamic Message Sign (DMS) server control, Traffic Signal server control, and Weather Monitoring Systems for advance knowledge of flooding adjacent to freeways.  All of this is housed in an online (zero-millisecond lag time) UPS- and generator-protected facility and makes for a fast-paced, fun place to work.

Traffic Analysis

Traffic Analysis is divided into two areas, recurring and nonrecurring.

Recurring traffic issues such as congestion can occur every morning and every afternoon while motorists are commuting to and from home and work. Ramp meters are one tool that reduce the amount of recurring congestion. Ramp meters are installed on a series of interchanges to control the amount of traffic entering the freeway. In general, the timing for ramp meters is related to the amount of traffic on the freeway. The green and red lights will have variable times depending on the volume of traffic on the freeway — ideally, the green lights will be timed so motorists can easily merge onto the freeway. A complex process of corridor evaluations are involved in determining the location and timing pattern of the ramp meters. The use of ramp meters improves both traffic safety and traffic flow.

Nonrecurring congestion is caused by a wide variety of events, such as funerals, football games, basketball games, baseball games, automobile races, mass evacuations, bicycle tours, construction activities, maintenance activities, etc. Staff prepare a weekly report on activities that will severely restrict traffic on highways and freeways. In addition, staff prepare a monthly report on all major incidents (e.g., highway and freeway closures, fatal crashes, large fires, etc.). Furthermore, staff participate in meetings to improve homeland (transportation) security.