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A ghost benchmark

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I found a benchmark a while back on a bridge near my house that doesn't appear on gc.com, and doesn't appear to exist in the NGS databases (via the links on the benchmarking page). The benchmark is in Gaithersburg, MD, where Rt-355 crosses Great Seneca Creek.


The coordinates are:

39 9.948N

077 13.677W


Attached are two pictures.




What should I do about this one? Perhaps someone knows how to work the NGS system better?




Edited by hybridgeek
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The images didn't come through. Could you repost them, so we can look at the disk? Do you have a picture of the setting/piece of the bridge?

The NGS database is a small fraction of the benchmarks on the ground in the US. Please read a more in depth response to this question on the FAQ at the top of the forum.

Once we take a look at the pic, we can give you better advice. Odds are it isn't in the database. In that case you can create a Waymark in the U.S. Benchmark category.

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This mark was set by the Washington Suburban Sanitary Commission (WSSC). While data for many of their marks have been forwarded to NGS for inclusion in the National Spatial Reference System, there are many more that have not. For information on their marks you need to contact WSSC directly

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Do you have a picture of the setting/piece of the bridge?

I don't have a picture, but it was set flush with the bridge, on one corner of it, near the date block; it was on top of the side peice.


Thanks for the help. I guess I'll give the WSSC a call at some point. I'm not sure it's important enough to me just to have another logged benchmark to really want to call the WSSC. I'm sure they know about it. I'll see... I'll post here if I do and it becomes official (for those Marylanders who want to log it or have attempted to log it).



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