Jump to content

Found a BM not listed on GC.com


WebiG

Recommended Posts

Hi, I found a benchmark and wanted to log my first one. Alas, a search on GC.com did not find it. I went to Waymarking.com, but could not figure out how to search for a specific benchmark to see if it is listed. The benchmark is in a pedestrian bridge in Portland, OR. Is there a way to log it? I have the lat/long, title, No., and elevation.

Link to comment

Welcome WebiG!

 

There are MANY benchmarks that are not in the GC.com database. If it is not in there then Waymarking is indeed the place to go.

 

When you are looking at Waymarking.com you should select the "US Benchmarks" Category. Then you can go to "Search Criteria" and put in an address or coordinates.

 

There are only a dozen benchmarks listed within 10 miles of Portland in Waymarking. Here they are: 12 benchmarks closest to Portland.

 

I would be interested in knowing the Lat/Long and No. and/or seeing a photo.

 

Good luck!

Link to comment

Hi Tilla,

I checked your list and "my" benchmark" is not listed. Here are the coordinates: N45 28.672 W122 41.854

It is in SW Portland on an overpass. It is titled: USGS & State Survey, No. A218, Elevation 479', 1934

Unfortunately, I cannot find the photo of it, so I can't post it on Waymarking.com - bummer.

Link to comment

Hi WebiG,

 

Unfortunately that one is not in the National Geodetic Survey (NGS) database. However, I did find it listed in the City of Portland’s benchmark database. It is their benchmark number 4199 and its description is: "A-218", SE COR. ON PARAPET, VIADUCT OVER BERTHA

 

Here is a link to its description on the City of Portland site (nothing exciting) - it is the second one in the list - towards the bottom of the page: A-218 Link

 

Congratulations on finding that.

 

If you want to look for a benchmark that IS in the geocaching.com database, here is a link to the one nearest to the A218 mark that you found: HILLVILLA

Edited by TillaMurphs
Link to comment

--------------

It is titled: USGS & State Survey, No. A218, Elevation 479', 1934

-----

WebiG,

 

You have found one of a rather unique group of Bench Marks.

 

TillaMurphs Photo

 

0b92ff69-978e-4574-b309-94acf83c90ad.jpg

May were set, but never surveyed in, under a Civil Works Administration program that was funded for just a few months in late 1933 and early 1934. Of the 470 or so set in Nebraska I have been able to GSAK filter only ten that have PID's and just five more that are an RM or AZ for a Triangulation Station.

 

http://www.penryfamily.com/surveying/statesurvey.html

 

This thread cost me several hours researching Oregon's CGS+SS potential, where it looks like just over 100 have PID's. I will add summary of that information to my earlier thread here:

 

HEARTLAND STATE SURVEY MARKS - http://forums.Groundspeak.com/GC/index.php?showtopic=269750&pid=4832199&st=0entry4832199

 

kayakbird

Link to comment

Welcome WebiG!

 

There are MANY benchmarks that are not in the GC.com database. If it is not in there then Waymarking is indeed the place to go.!

 

Thanks so much for the information! I have so many benchmark discs/coordinates that I've been unable to identify--many at Hoover Dam and some discs in my local area. One I found in the Las Vegas desert area is "US General Land Office Survey 1933." can't wait to get my notes & photos out to (hopefully) log these in!

Link to comment

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...