WSDOT To Study Traffic Patterns on I-5

Over the next two weeks, crews will study traffic patterns between Interstate 5 interchanges, Joint Base Lewis-McChord and the greater Lakewood area.

But they aren’t going to use traffic-counting devices. No one is going to be standing on a corner counting cars, either.

As part of an “Origin-Destination” study being conducted by the Washington State Department of Transportation – which is part of a larger I-5 JBLM Interchange Justification Report (IJR) - crews will be installing solar-powered devices that can pick up Bluetooth signals and track the routes of drivers.

Those devices will track how many vehicles use I-5 to access JBLM and surrounding areas. That data will help determine the South Sound’s transportation future in terms of what improvements are needed in one of the most congested regions in the state.

“The study is ultimately going to help determine how big I-5 should be and whether local roads should be built to alleviate that,” said Desiree Winkler, Transportation Division Manager at the City of Lakewood.

The devices, called “BlueMAC Readers,” identify partial Bluetooth signals, everything from a cell phone to a wireless headset to Bluetooth-enabled vehicles.

According to the Transpo Group, which is installing the equipment, the readers provide one-way, passive communication from a vehicle or mobile device. Each reader is equipped with a transmitter - same as any cell phone - that uploads the data in real-time to the cloud. The readers can be monitored remotely to review their performance and track travel times and patterns via a secure online portal.

An obvious question: Do the devices spy on drivers and infringe on privacy?

The answer: An emphatic “No.”

The data that the devices are collecting are partial Bluetooth signals, so they can’t be traced to a specific person or device. Many of the devices will be installed on JBLM – where there are strict privacy regulations and airfields with navigation systems - and they’ve been approved by base officials.

“This is really to understand the traffic patterns of cars going in and out of JBLM,” Winkler said. “Currently, the assumption is cars are using I-5 to get from one point on the base to another. This is a good way to know exactly if that’s happening.”

Pictured: An example of a solar-powered, BlueMAC reader that was installed in Seattle. Photo courtesy of Transpo Group.