Everyday Mysteries: How road tubes work, and what they do

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HUNTSVILLE, Ala. (WHNT) – You may not even notice them when you drive over them, but they’re all over Huntsville. They’re rubber tubes than run across the road.

Huntsville Traffic Engineer and Analyst Tom Sisco tells us, “We call them our road tube counters.”

The tubes convert traffic into data. And despite the high-tech mission, Sisco notes it’s a low-tech tool, “It’s just a simple, basic rubber tube.”

He elaborates, “A lot of people think it’s the weight of the vehicle, but it’s the pressure of the tire pushing air through the hoses.”

Basically, when you drive over the tube, you get a puff of air measured by a box. It records the time and the type of vehicle. If you’ve got two of the tubes, you can record speed.

Strategic deployments over a two-year period get a full picture of the city by counting the cars that cross them. They simplify that data down to this map, with the colors showing how much traffic crosses a given type of road.

Sisco adds, “That data is useful for realtors, for commercial developers, for billboard companies that are looking for advertisers.”

They also use the data for planning road projects.

The sensors can tell which kind of vehicles travel a given road, which helps folks in the engineering department when they have questions. They can identify unusual patterns and help correct them, alleviating overwhelmed arteries.

Of course, people come up with their own theories too.

Sisco chuckles, “We’ve even had people before think that we’ve got a camera hooked up to the device, and they want to know if we’re recording how fast they’re driving over the tubes and taking a snapshot of them. And no we’re not.”

In fact, they don’t do any real-time monitoring of the tubes.

Just planning.