Findings from the 2007 National Traffic Signal Report Card
The 2007 Transit Signal Self-Assessment, a voluntary self-assessment survey, was taken by 417 agencies in the US and Canada in 2006, in order to determine their "report card" grade for traffic signal operations. This report card uses a questionnaire to determine grades for management, individual signal operations, coordinated signal operations, signal timing practices, traffic monitoring and data collection, and maintenance. The self-assessment is one way for agencies to evaluate their existing practices and create a plan to improve their traffic signal operations and management. The 2007 National Traffic Signal Operation Report Card Technical Report synthesizes the results of that survey and provides some case study examples of improvements made by upgrades to signal timing and the benefits received by the travelers in their service areas. It also details estimated costs to upgrade and retime the national traffic signal infrastructure over 10 years.
Assuming the U.S. has 270,000 signals, the annual costs associated with signal timing can be calculated. These costs reflect updated prices from the 2005 report.
Each year 1/10 of the controllers are replaced
270,000/10 = 27,000 controllers per year
Furnish and Installation costs are approximately $13,500 per signal
Total cost is $367.2 million per year
Signal retiming interval is every three to five years
$3,000 per signal
Total cost is roughly $217.6 million per year
One technician maintains 30 signals
270,000/30 = 9,000 technicians
$60,000 per technician
Total cost is roughly $540 million per year
Grand total cost for signal timing per year across the U.S. is $1.125 billion.
Costs to update signal timing remains about $3,000 per intersection. Cost to furnish and install a new signal is about $13,500. Total annual costs for an update to the national signal system would cost $1.125 billion annually.