I’ve noticed small circular plastic tags on patches in the streets around here and was intrigued. Apparently they’re called A-tags (Asphalt tags) that mark who did the work and what’s underneath. Around here, it’s mostly natural gas and electric work, but I imagine in places like NYC there are all sorts of things.
They are a remarkably recent invention, I’m wondering how wide spread they are. Do they use them around where you live? Are they used outside the US?
I’m in Chicago, and I can’t say I’ve ever noticed such a thing. That doesn’t mean they don’t exist here, they’ve just never caught my attention if they are here.
As long as they’re not proud of the road surface, the blade is going to pass right over the top of it. Plus, they’re a bit more than just the flat part you see (not much more, but a bit).
Seems like a couple of freeze-thaw cycles would push those right up out of the ground, like rocks in a farm field. Then the next snowplow would remove them quite cleanly. Leaving a nice little pit in the road, to incubate into a lovely pothole.
A tag of any color with a nail in the center might be a survey marker.
These underground utility ID tags might be related to GIS mapping. Right now, most underground utilities are identified by spray paint markings on pavement, in areas targeted to dig.