There could be many different forms that survey markers could take, but, for example, here’s a couple pictures of some that I’ve come across on trails:
I’m not sure how to tag this exactly. I couldn’t find anything existing on the wiki.
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I wouldn’t map these as they seem ephemeral, not intended to last for than a few days/weeks.
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Depends on the specific survey marker in question. Not all are as seemingly ephemeral.
At any rate, survey markers are extremely important for mapping cadastral data (ignoring the controversy around that). OFC, a rough estimate of a survey markers GPS coordinates aren’t a replacement for a professional survey, but I would argue that their physical location and characteristics are still useful information to map.
What about man_made=survey_point? I would map them only if I expect them to be on the ground at least half a year or so…
https://wiki.openstreetmap.org/wiki/Tag:man_made%3Dsurvey_point
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Such pegs are often used to increase the visibility of a permanent survey point set in the ground. The permanent points usually come along as a steel pin, a round steel plate or a stone block at the roadside, but often are hidden below vegetation. When works along the road are in progress, the survey points are highlighted with such pegs. In such cases I map the permanent survey point as already said by @Tomas_J.
In other cases such pegs are set as temporary survey markers and either removed after work has finished or just left to disappear by the time. In such cases I do not map them at all, as proposed by @dieterdreist
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I don’t think that’s what I’m looking for. From what I understand, that’s for features where a surveyor affixes survey equipment to conduct a survey. That’s not a survey marker for marking property lines.
Yeah, these would be what I’m technically referring to.
I wonder if Key:marker - OpenStreetMap Wiki might be what I’m looking for.
key:marker is a generic tag for all kinds of markers. As such it is valid to be used for survey points but as there is also the more specific tag man_made=survey_point for those, I personally prefer to use that one.
And it perfectly fits these road side survey markers like steel pins, steel plates or marker stones with the appropriate subtag survey_point:structure=pin/medallion/block.
The DMS for the marker is often stamped right into the head of the monument itself, and should be a couple orders of magnitude more reliable than a GPS (even taking into account seismic activity with the exception of New Madrid), particularly in cooler climates (the western US is notorious for heat induced measuring errors in 19th century surveys) and more recent decades. That said, I wouldn’t map the temporary markers pictured assuming the surveyors didn’t stake the monument just for visibility sake, but rather map the monument itself. This is especially true for monuments within the highway right of way, as many DOTs (Oklahoma, California and Oregon for sure from experience) will often paint large + markings with the monument centered in the +, handy for imagery alignment purposes.
These are both kinds of survey points suitable for the tag. There’s subtags for the specific kind of survey point.
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