In the previous blog article, National Traffic Signal Report Card 2012 from the NTOC – Part One, we reviewed previous results of NTOC Report Cards and this year’s results including two of the five criteria that attribute to the overall grade.
This week’s blog article will focus on the importance of signal operations as well as the remaining three criteria that contributed to the NTOC Report Card.
The Importance of Efficient Signal Operations
Efficient signal operations have a significant impact on transportation networks, delays and overall driver satisfaction. Improving signal timing and operations has the potential to provide the most benefits than any other operational measure in the traffic engineering toolkit.
Regular signal timing updates has a benefit/cost ratio between 20:1 and 55:1 and tens of millions of dollars in annual user savings. These figures were found by The US Department of Transportation Intelligent Transportation Systems Joint Program Office who maintain a benefit-cost database that documents traffic signal studies conducted by various agencies.
Within the last 20 years, delays on roadways have been consistently increasing. The Federal Highway Administration has found that about 5-10% of traffic delays are the result of traffic signals. This is about 295 million vehicle hours in delays on American roadways. The 2011 Urban Mobility Report found that in its reporting areas, 61% of the street miles in cities had some level of traffic signal coordination which then reduced delay by 21.7 million vehicle hours.
The Results of the 2012 NTOC National Traffic Signal Report Card
The 2012 NTOC National Traffic Signal Report Card is graded based on 5 criteria: Management, Traffic Signal Operations, Signal Timing Practices, Traffic Monitoring and Data Collection and Maintenance. In the last blog article, we reviewed Management and Traffic Signal Operations which scored grades of D and C.
Signal Timing Practices: Grade C
The Signal Timing Practices scored a C or 76. The questions for this section of the Report Card focused on the frequency of signal timing, the number of operational detectors as well as the overall effectiveness of the signal operations. This section scored the highest for all signal systems except systems with less than 50 signals.
The Report Card found the following for Signal Timing Practices:
- Two-thirds of agencies perform a comparative analysis of timing parameters including cycle lengths, offsets, and phase sequences
- 71% stated having strong or outstanding procedures for considering different signal phase sequences in order to minimize interruption of traffic progression
- 73% stated having strong or outstanding procedures for operational strategies which promote efficient traffic movement in light traffic flow periods including night time
Although this section has received the highest score within the Report Card, agencies need to ensure that signal timing policies and practices are always documented. Signal timing plans need to include all signal timing parameters in order to meeting demands during all periods including weekdays, weekends, holidays, special events and incidents/emergency situations.
Traffic Monitoring and Data Collection: Grade F
The Traffic Monitoring and Data Collection scored an F or 52. This section continues to be the lowest scoring section of the Report Card regardless of signal system size or agency type. One reason for this is the lack of clear objectives for a traffic signal program which would include performance management. Without this, it’s difficult for agencies to support consistent traffic data collection and improve upon their current efforts.
The Report Card found the following for Signal Timing Practices:
- 50% of agencies stated that they do not assess the quality of data collected
- 49% of agencies reporting having little or no consistent or ongoing performance management system to assess operational objectives
- Two-thirds of agencies don’t have a process in place for archiving existing data
In order for agencies to improve their scores for Traffic Monitoring and Data Collection, they’ll need to establish processes for data management. This includes checking data quality, archiving data, sharing data and ensuring correct data is being used in signal timing plans.
Maintenance: Grade C
The Maintenance section of the Report Card scored a C or 73. This is the second highest scoring section and is the highest scoring for signal systems with less than 50 signals. This section has struggled in the past due to limited resources but many agencies are improving their signal timing maintenance due to the low costs and high benefits.
The Report Card found the following for Maintenance:
- 80% of agencies have policies and procedures for reported critical malfunctions at intersections
- 70% of agencies reported having procedures in place to ensure the equipment is functioning
- 87% of agencies have a maintenance management system in place which in some instances is paper-based record keeping or spreadsheets
Limited resources have been an issue in the past. In order to continue to improve in Maintenance, agencies will need to proactively maintain their entire signal system rather than just addressing the most critical issues.
How to Improve with Signal Timing Procedures and Processes?
The major section for improvement within signal timing based on the NTOC Report Card is traffic monitoring and traffic data. Miovision provides an effective solution that can solve many of the issues that agencies are experiencing with the Scout Video Collection Unit.
Miovision’s Scout VCU collects traffic data via video, which is highly accurate and auditable. Traffic studies such as Turning Movement Counts (TMC) and Average Daily Traffic (ADT) have a proven accuracy rate of 95% or more. The Scout VCU captures video which provides the ability to review and audit data. It also provides additional insight into traffic oddities such as possible traffic accidents.
For agencies that do not collect their own data, Miovision provides Traffic Data On Demand. Traffic data is collected using the Scout VCU and is deployed by our Partner Network across Canada and the US.
All of the data and video collected by the Scout or Traffic Data On Demand is stored online using Miovision’s traffic management platform, TrafficDataOnline.com (TDO). This provides the ability to share data with desired stakeholders through a public portal and store all data in one centralized location.
Whether utilizing the Scout VCU or Traffic Data On Demand, Miovision’s solutions maximize current resources for data collection and traffic signal timing by providing an efficient method for collecting traffic data. This provides time savings and the ability to do more with less.