The Austin Transportation Department, like most other transportation agencies, deploys traffic counting devices to collect data to use for a variety of transportation-related purposes. There are a variety of different devices and techniques we use, and a whole multitude of things we can use the collected data for.
For example, we deploy street tube counters, also known as Pneumatic Tubes, to count vehicles to determine if a new stop sign is warranted or adjust traffic signal timing. We also use them to determine if a school zone is effective, adjust speed limits, plan for street closures during road work/maintenance, and more.
Here are just a few examples of traffic counters used by ATD:
Street tube counters (Pneumatic Tubes)
Black tubes lined across the street and connected to a computer on one end. A single tube collects just the number of cars on any given road in one hour intervals throughout the time deployed. More than one tube can be deployed to detect speed and types of vehicles between two tubes. These are most often deployed on a temporary basis.
Mounted to signals and sometimes standalone poles, Bluetooth counters detect multiple transportation modes and are typically a permanent piece of infrastructure. The counters detect both the amount of traffic and speed of vehicles and can be a variety of shapes and sizes.
At some intersections in Austin, there are special cameras attached to traffic signals that detect if vehicles are present. The cameras don’t collect any identifiable information, such as license plates, or record video; rather, a signal technician uses software to “draw a shape” around a traffic lane in the camera’s view. As a vehicle travels through the shape, it is counted.
We also have different techniques to count people walking or riding bikes, which helps us determine where we should put crosswalks, pedestrian signals, bike infrastructure and more. The data is often stored after the original need is completed in the event the City needs to reuse data for another project in the future.
Tampering with or intentionally damaging City-owned property is a crime. In fact, intentionally damaging the expensive computer systems attached to traffic counters could be a felony offense. In addition to being a crime, damaging traffic counters can delay much-needed safety projects such as school zones or stop signs because more staff time is spent revisiting the same street.
If you see a traffic counter and are curious what it is being used for, please call Austin 3-1-1.