Scottsdale, Arizona sets up wireless mesh network to relieve traffic congestion

Scottsdale’s New Intelligent Transportation System (including a wireless mesh network) gives operators hands-on control over traffic dynamics and dramatically lowers the city’s operating costs, paying for itself within four years.

Scottsdale, Arizona has deployed a wireless mesh network as part of its “intelligent transportation system” (ITS) to deal with traffic problems in the city. The ITS communications platform connects wirelessly to video cameras, traffic signal controllers and dynamic message signs on arterials throughout the city, so traffic can be monitored from a central command center. This allows the city to control traffic lights, send out emergency personnel or traffic wardens to clear bottlenecks, especially when there are special events or accidents.

scottsdale wireless mesh network scottsdale wireless mesh network monitoring traffic

The wireless mesh network deployment took one year and cost $975,000. This amount includes the maintenance cost for the first year, but excludes the cost of the cameras. After the first year, Scottsdale is allotting $10,000.00 per year for wireless hardware replacement due to accidental damage, etc.

The wireless mesh network serves as a multi-hop-enabled backhaul sustaining throughput up to  100 Mbps. It relies upon the city’s fiber network for backhaul.

Scottsdale’s wireless mesh network ITS consists of 90 Firetide HotPort 7020 wireless mesh nodes, Firetide HotView Pro network management software, and 86 pan-tilt-zoom digital video cameras. To monitor traffic flows more effectively, the video cameras are strategically placed on traffic signal poles at intersections throughout the city, and connect directly to the city’s network via Firetide wireless mesh nodes. Live video feeds of the most heavily trafficked intersections are continuously displayed on a large video wall and on desktop monitors in the command center, where operators can identify congestion and spot incidents as they happen — enabling them to take corrective action and remedy congestion before it worsens.

Benefits of the ITS network are:

  • Reduced traffic incident delay. When collisions, spills or stalled vehicles occur, operators can adjust signal timing immediately to reduce the delay.
  • Pro-active traffic management through work zones.
  • Enhanced roadway safety. The system enables immediate detection and reporting of incidents to police, emergency services, media agencies, and the public.
  • Effective event traffic management. Costs are dramatically reduced by centralized traffic management and eliminating the need to deploy police officers at various locations.
  • Consistent travel times. The ITS enables Scottsdale to keep travel time on city streets steady and, where possible, even reduce travel time as traffic volume increases due to population growth.
  • Improved environmental conditions and reduced fuel consumption.

Scottsdale covers an area of 185 square miles (479 square kilometers) and has 225,000 residents. The city’s traffic problem is made worse not just by its residents’ extreme dependence upon the automobile, but also by its proximity to Phoenix. Large numbers of visitors converge upon Scottsdale for events such as the PGA golf tournaments.

Scottsdale wants to use the latest technology to improve the city’s critical infrastructure while saving taxpayer money. Migrating from its existing leased-line communications network to the newly deployed Firetide wireless mesh network will save the city approximately $250,000 a year in lease fees alone, enabling the city to achieve full ROI in only four years. The ITS platform was procured through national provider Unicom Government Inc. (formerly known as GTSI Corp.), of Herndon, Virginia, via the U.S. Communities contract.

The city selected Firetide’s wireless infrastructure network because it proved to be the only solution that could deliver 100 Mbps of very low latency throughput while maintaining “low-sight” (less than 20 feet above the ground) wireless connectivity over long distances. Because the network supports up to 15 consecutive links, or “hops,” it can easily be routed around buildings and trees rather than requiring giant 300-foot towers to operate above these obstacles. The Firetide network’s built-in multicast and traffic filtering functions also eliminated the need to purchase external switches, saving the city $1,500 at every camera location.