What are Those Weird Black Cables That Run Across Idaho Roads?

What are those black tubes on Idaho roads?

Winter, spring, summer or fall, if you've ever driven in Idaho, you may have noticed strange black tubes that run across the road. It seems like they come out of nowhere and disappear just as fast, leaving a lot of Boise drivers confused about what they do.

Those black, cable-like tubes are actually a type of road sensor called pavement sensors.They're designed to collect important information about road conditions like temperature, moisture, and even the weight of cars and trucks that drive over them.

The data helps the Idaho Department of Transportation make better, more cost-effective decisions about road maintenance, traffic management, and real estate development.

What are pavement sensors made of?

Pavement sensors are made from rubber or plastic with a series of wires embedded inside. They look a lot like cable wires which is probably what makes Idahoans and visitors so curious about them.

The internal wires are connected to a control box somewhere nearby that collects and sends data to IDT for analysis. The sensors are typically installed in pairs, with sensors for each lane of traffic on highways and surface streets the state.

Doesn't Idaho's frigid winter weather affect sensor tubes?

The short answer is yes, but not in the way you might think. Pavement sensors are designed to withstand harsh weather conditions and can still work just fine even when they're covered in snow or ice.

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One of the coolest things about the sensors is their ability to predict when ice and snow will form on the road, allowing IDT to take action before road conditions become dangerous.

Sensor tubes can help manage traffic.

The Federal Highway Administration says pavement sensors can also be used to detect traffic flow and break up congestion.

They measure the weight of passing cars and trucks, relay the number of vehicles on the road, and how fast traffic is traveling. They can even sense car accidents. All of this information can help IDT adjust traffic lights and reduce traffic jams across the Treasure Valley. Pretty cool, right?

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