The Las Vegas Valley has experienced the most rapid growth of any metropolitan region in the country. Along with this phenomenal growth, has come increasing traffic problems and air quality concerns. Public officials have aggressively pursued an ambitious program of public works improvements to address traffic demand. They have established a program for improving the effectiveness of the existing roadway network by upgrading and enhancing the Las Vegas area computer traffic system, better known as LVACTS.
LVACTS was established in 1983 as one of the only multi-jurisdictional centralized traffic signal systems in the United States. LVACTS is an agency that is jointly managed by the City of Las Vegas, Clark County, the City of North Las Vegas, the Clark County Regional Transportation Commission, the City of Henderson and the Nevada Department of Transportation. The existing control system has now reached its capacity, and many traffic signals now being constructed cannot be accommodated on the existing system.
Since that time the technology of traffic signal systems has improved dramatically. As traffic congestion has increased, so has the need for these expensed capabilities.
Based on the results of a feasibility study, the Regional Transportation Commission included the LVACTS upgrade project in the Federally funded Congestion Mitigation and Air Quality improvement program, which was established as part of ISTEA. In 1993 the Nevada Department of Transportation, in cooperation with the LVACTS participants, secured the services of Barton-Ashman Associates, now known as the Parsons Transportation Group, to proceed with design. Construction of the system is now underway.
Traditional traffic signal systems have been designed from a traffic control center outward. The existing system is an example of this highly centralized approach. The central computer directs on a second-by-second basis the individual actions of all 475 plus traffic signals that are now part of the system. The new system follows an innovative approach where all the individual traffic signal controls is contained at the intersection using advanced transportation controllers. This decentralized, or distributed approach, will allow the system to provide reliable operation even when communication systems fail. Also, the distributed approach will allow the replacement of the existing mainframe computer with a network of inexpensive and easy to maintain microcomputers.
In addition to increasing the features the reliability of the traffic signal control system, the design concept has incorporated a video surveillance system. Closed circuit video will give operators the chance to observe traffic conditions and make adjustments from the downtown traffic management center. The video system will greatly increase the effectiveness of the LVACTS staff.
To provide the LVACTS operators with access to the intersection controllers and video cameras, system designers have devised a two-tiered communications network. The system has been divided into nine regions and all intersection controllers will be tied to a hub located in each region. These regional hubs will be connected to a backbone communication system using high frequency microwave.
Several different technologies will carry video and controller signals from the cameras and intersections to their respective hubs. These technologies include data radio, ultrahigh frequency microwave, fiber optic cable and special equipment designed to move video along the existing copper cables that are used by the existing system.
In total the upgraded LVACTS communications network will showcase the most advanced technologies available, traffic management systems.
An ironic note -- a recent ruling by the Federal Communications Commission will remove from public access the 31 gigahertz radio band. This band was to be used on the LVACTS project for video surveillance communications. The FCC's rejection of the State's license application will have a significant impact on the reliability and efficiency of this new traffic signal system.
The purpose of the signal system is to provide the capability to move traffic as efficiently as possible. Traffic signals cannot add capacity, but they can allow traffic to make best use of the capacity by distributing it fairly to all movements.
The current system imposing constraints on the signal timing because of its limited capabilities. The new system will be capable of controlling an infinite number of intersections, able to maintain signal coordination during central system and communication network failures, improve overall traffic progression during off-peak and heavy traffic flow times, improve pedestrian crossing movements, permit system operators to make signal timing adjustments through the video surveillance system, and have the capability to be expanded for functions such as freeway management.
We urge you to continue the funding categories now available from the ISTEA bill that allow for traffic control systems such as LVACTS. This type of project is very cost-effective and has positive impact on air quality.