The Uses of Traffic Counts Explained

Traffic engineers and transportation planners use traffic volume data for a myriad of analyses.  Here are the most common types of short term counts collected with their uses:

• 2 (or 3) Hour Turning Movement Count (vehicles turning at an intersection/junction):  Used for peak hour capacity analysis per the Highway Capacity Manual to determine the Level of Service at an intersection, leading to changes in traffic control, expansion of the intersection, and adjustments to traffic signal timing plans.  2 or 3 hours is collected to capture the busiest 60 minutes of data in the peak period.
• 13 Hour Turning Movement Count:  Used to ensure you have the a.m., midday, and p.m. peak hour counts to perform the above analyses.  It also provides enough data to perform stop sign and traffic signal warrant analyses per the Manual on Uniform Traffic Control Devices.
• 24 Hour Turning Movement Count:  Used to perform Level of Service and Warrant analyses per above, plus provides daily traffic volumes on each leg of the intersection.  Daily traffic volumes are used to report usage to state and federal databases and perform daily planning level analyses per the Highway Capacity Manual.
• 24 Hour Point Count (vehicles going back and forth at a point):  Provides a daily traffic volume on a roadway segment used to report usage to state and federal databases and perform daily planning level analyses per the Highway Capacity Manual.
• 48 Hour Point Count:  Same use as a 24 Hour Point Count, but the two days of data are averaged to provide a more representative daily traffic volume.
• 48 Hour Turning Movement Count:  Same use as a 24 Hour Turning Movement Count, but the two days of data are averaged to provide more representative traffic volumes.

The industry began collecting 2 Hour Turning Movement Counts in the 1950s to utilize the first Highway Capacity Manual.  People would sit on the street corners with pencils and paper tallying traffic counts.  Pneumatic tube counters were invented in the 1970’s to do 24 and 48 Hour Point Counts.

Miovision pioneered video camera technology a decade ago to make long-duration turning movement counts feasible.  We’ve pioneered making 48-hour turning movement counts affordable at www.SpackSolutions.com. 

Here are the Top 10 Reasons to Collect Video-Based 48-Hour Turning Movement Counts:

1. Covers All Planning and Engineering Analysis Data Needs
2. Replace Tube Counters, which have a host of safety and reliability issues
3. Identify and Remove Anomalies
4. Obtain a True Average for your Peak Hour Data
5. Fully Evaluate Traffic Signal Warrants
6. Establish Greater Credibility for your Study
7. Keep the Video File for Backup
8. Engineers can Scroll through the Videos Later for First Hand Knowledge
9. Create Better Signal Timing Plans
10. Give Yourself a Competitive Advantage (for Consultants)