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California surveyors - bay area

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(@jseace)
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I am doing some photo control on hwy 92, east of half moon bay. I found a bench mark labeled "bm 216" on the half moon bay quad sheet.
BUT ngs does not have info of this bench mark. Does anyone have a way too find the data for this bm?
It is a brass cap on a bridge . It has gwk 7.9 1946 & reset 1965 stamped on it. Any help would be appreciated.
Thanks in advance

 
Posted : November 16, 2015 3:41 pm
(@mkennedy)
Posts: 683
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Around Pilarcitos Creek

 
Posted : November 16, 2015 5:03 pm
(@bajaor)
Posts: 368
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If it's along a highway, try your Caltrans district Surveys office for that mark or other un-published marks. Alternately, USGS Menlo Park or USGS Rocky Mountain Mapping Center?

 
Posted : November 16, 2015 5:25 pm
(@lanceboyle93101)
Posts: 154
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216 is likely the approx. elevation
scale or Garmin a lat/lon and Search NGS datasheets by that criteria.

 
Posted : November 17, 2015 12:36 am
(@skwyd)
Posts: 599
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Also, if you have a Lat and Long for the BM (even an approximate one) you can use this site: http://www.ngs.noaa.gov/cgi-bin/datasheet.prl to do a radial search for any NGS control monuments around that area. It sometimes will turn up several documents, but if you grab the text, you can do a search for the text stamped on the cap and possibly turn up the monument that way.

 
Posted : November 17, 2015 1:29 pm
(@norman-oklahoma)
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You might try http://ask.usgs.gov if Caltrans or the County Surveyor can't help you .

 
Posted : November 17, 2015 2:19 pm