Motorists baffled by strange addition to traffic signs: 'What are they?'

If you've noticed strange black boxes attached to traffic signs on your morning commute, you're not alone. But what are they?

One Western Australian motorist decided it was time for answers, and appealed to a popular Facebook group for help.

“Anyone know what these are? They are all over the Balcatta industrial area. It looks like a speed camera,” he said.

Small black box chained to road sign to monitor movement of motorists
Motorists speculated that the boxes could be police equipment. Source: Facebook

Accompanying the resident’s post are two photographs showing one of the black boxes, which is chained to a traffic sign.

The boxes appear to be made of hard plastic, with a built-in camera lens or sensor, and are placed close to the ground.

Hundreds of group members offered theories about the function of the odd-looking boxes.

“I've seen a couple around and I would assume it's to catch people doing mad skids,” one person wrote.

“Looks like a speed camera,” commented a second.

“Motion video cameras used mainly for security or hunting. Could be a taskforce op trying to catch hoons or theft,” said a third.

“I think they count cars so the council can see how many cars are utilising the street,” speculated another.

Although their appearance resembles something out of a sci-fi film, it turns out the boxes have a far less sinister function.

Black box function identified

Yahoo News contacted multiple city councils, the department of Main Roads, and the Western Australian Police Force to confirm the purpose of the boxes.

Motorists can feel at ease knowing that the black boxes are not unmarked police equipment.

In fact, it turns out that the boxes have been installed throughout the state on behalf of Main Roads to assist with video surveillance of traffic movements.

The data obtained by the boxes is intended to be used in future road network development activities.

Main Roads is also investigating options for signage at box locations to make residents and motorists aware of their purpose.

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