TERRA was selected as the prime consultant by the Ar-Riyadh Development Authority to provide traffic engineering services for an aggressive three-year program to collect citywide traffic data. As part of this project, the TERRA Team will be responsible for collecting traffic data using various types of state-of-the-art equipment. The counts include temporary duration locations of up to three days using road tubes at 700 sites, automated video traffic data collection systems at 500 sites, and radar traffic microwave sensors (RTMS) at 250 sites.

Additionally, TERRA will be designing and installing 40 permanent counting stations to provide real time vehicle data through lane monitoring which will be transmitted to the city’s local monitoring facility. This permanent system will also be capable of measuring volume, speed, incident detection and headways with volume accuracy of 95% or greater, speed of vehicles with 90% accuracy, classifications of vehicles to within 30 CM. The system will utilize wireless magnetic sensors placed in the pavement which relay traffic back to the main building through access points and repeaters.

TERRA will also be responsible for developing a GIS database system which places all of the traffic data on maps with the date of counts, traffic volumes and other pertinent data. TERRA’s team of traffic engineers will provide traffic analysis and modeling of the recorded data at key congested intersections to determine remedial actions which could be evaluated for implementation. These can include a wide range of scenarios from adjustment of traffic signal timing to recommended changes to intersection or corridor geometry.

At six month intervals and at the completion of the project, TERRA will provide a detailed report including the data collected and remedial suggestions. The project will also evaluate how the development of the Riyadh Metro system changes traffic patterns in the area.


Ar-Riyadh Development Authority