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Details for Benchmark: AA1873

N 37° 23.336 W 121° 59.198 (NAD 83)

Altitude: 26

Coordinates may not be exact. Altitude is GPS OBS and location is ADJUSTED. (more info)

Location:
In SANTA CLARA county, CA View Original Datasheet
Designation:
HPGN D CA MISSION
Marker Type:
survey disk
Setting:
aluminum alloy rod
Stability:
Probably hold position/elevation well.

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I found this one while doing the nearby multi-cache.

Found in good shape. Witness marker and metal plate covering benchmark are now a lovely matching shade of Electric Pepto Bismol.

Found it! I missed this one the last time I was here. I didn't realize it wasn't right next to the witness post. It's a few feet away under a metal plate.

[Photos:]
photoCloseup HPGN-D 1992
photoArea HPGN-D 1992

Found HPGN-D/1992 as described in good condition.

[Photos:]
photoAA1873
photoAA1873 and cover
N 37° 23.336 W 121° 59.199

Found in good condition under an iron plate.

Stopped by last week to pick up a puzzle final only to realize there was a benchmark here after I got home. D'oh! Came back today to make the find.

[Photos:]
photoAA1873 Benchmark Cover
photoAA1873 Close Up of Benchmark HPGN D CA MISSION
photoReverence View

Found where described

My GPSr's read ...
etrex N37 23.337 W121 59.200
etrex-10 N37 23.337 W121 59.199
Apple iphone 5c N37 23.336 W121 59.200

[Photos:]
photoMark
photoEye level
photoFor reference

Discovered while geocaching.

Found 31-Mar-2017 02:25L.

Or at least I think so. The only thing I found at the site was the fiberglass survey marker pole with the correct number hand-written on it. I never did find any disc, even after moving some debris out of the way to see if it was there, and checking both sides of the fence as well. If there is a disc, it might be covered by dried mud as if it had been flooded recently.

I did eventually find the multi-cache which relies upon the information at this benchmark. :)

Our first benchmark!

Found the cache, so also got the benchmark.

As most of the recent finders, found the survey disk while doing the multi cache. It was covered by some debris.

Found it while getting the associated Multicache.

Spotted this while picking up a nearby cache.

Spotted the witness post easily. Cheers!

241.

Found while locating a nearby geocache.

[Photos:]
photoKfromCA at BenchMark

I logged this in connection with the new geocache, GC6KR0H. I measured N37 23.336 W121 59.200 for the position.

Found the witness post and the benchmark. Took readings as this is a high precision benchmark location. I want to compare my GPS with a firm number.

[Photos:]
photoMarker

Found it today.

[Photos:]
photoPic1
photoPic2

No problem finding this one once I stopped trying to make it at the bottom of the little hole next to the marker.

[Photos:]
photoAA1873

Oaknest and I found this benchmark.

Found at lunchtime with CarlottaP. Everything in good shape.

[Photos:]
photoAA1873

Disk was under the wather but I touched it.

[Photos:]
photoAA1873

Out logging SCVWD BMs, and grabbed this one as well.

[Photos:]
photoAA1873 (in situ)
Area was muddy from recent rains, but BM was dry (as opposed to when I visited a month or so ago and the BM was submerged). Still had to remove mud from the BM itself.
photoAA1873 (closeup)
Picture of the BM after a quick spit shine

My GPSr: N 37 23.335, W 121 59.198
The protective cover was missing, but the mark is easy to spot. I spotted two other benchmarks in the local area: City of Santa Clara BM C-6 (aka SCWVD BM-79, a brass disk) and City of Santa Clara BM D-3, a "chiseled square". Will post a few images. -Batch218-

[Photos:]
photoSurvey marker
photoMarker with GPSr
photoIn situ.
photoSCBM C-6 / SCVWD BM-79
photoSCBM D-3

Third BM found in the area.

[Photos:]
photoIMG_0734

found it.

Found the benchmark while seeking the nearby bison tube. Will have to go back for the bison tube during the day and to record the information for the cache.

A benchmark on Thanksgiving Day. Gobble Gobble.

[Photos:]
photoAA1873 San Jose, California
AA1873 San Jose, California. And a cover that keeps it clean and safe.

Found it near another cache.

[Photos:]
photoBenchmark near mission college.
Benchmark near mission college.

Found it and the nearby cache! In good condition.

found it and the nearby cache!

Took another gander at this one while waymarking the nearby SCVWD benchmark (number 79)

N37 23.333 W121 59.203 according to my Vista CX

N 37° 23.335 W 121° 59.198 - found with cache

[Photos:]
photoAA1873
A surveyer had her instrument set up, so I couldn't clear away the dirt to show the BM disk better.
photoBM AA1873 post nearby

found it

N 37 23.337 W 121 59.200, found with adjacent cache.

Found with the cache.

Found it with the cache! This is probably the most popular benchmark in the area. :)

Found this one while seeking the nearby cache. 50sumtin

cache and benchmark combo!

Found with the nearby cache. Very cool!

One of many bench marks I have found and saw no reason to log previously.

A cache and a benchmark, what more can one ask. 6-6-6

Found the benchmark, but not the micro. Muggled? Poor eyesight? Who knows. Looks like things got a bit muddy, and yuckky, as the area was rutted pretty badly. The benchmark was covered in dried mud, but there were plenty of signs leading to it, so it was easy to find.

Found this one after finding bullit's hide. Thanks. Attached is a picture too.

Also found the SCVWD (Santa Clara Valley Water District) BM described in the NGS description. The disk is a bit dirty, but in good condition otherwise.

Another find via Bullit's cache. Thanks!

Another grab via bullit's cache.

I also found this due to Bullit's cache.Thanks

Found this one thanks to Bullits cache!

Had a little assistance in finding this- I'm pretty sure that a lot of people may be logging this one soon...

Found as described on the NE corner of intersection.

[Photos:]
photoAccess cover
photoAA1873
photoWider shot showing location

Found this benchmark while looking for HS2937 at http://www.geocaching.com/mark/details.aspx?PID=HS2937. Did not find HS2937.

[Photos:]
photoHPGN D CA MISSION - Disk -Santa Clara, CA - AA1873
Somebody painted it orange since the last log.
photoBM79 - Disk - Santa Clara, CA - AA1873
The Santa Clara Valley Water District benchmark.
photoHPGN D CA MISSION - Witness Post - AA1873
The witness post and 6 inch hole. The cover was missing but the orange circle is where it was at one time.

Was completely obscured by dirt... also found the SCVWD BMD nearby. First Benchmark! :-)

[Photos:]
photoDSCN5998.JPG
photoSCVWD BM

The location is easy to find, what with the orange/pink paint around the hole. With the cover missing, some mud had accumulated on top of the mark itself, but it only took me a few moments to remove the mud so I could see the mark.

Finally, logging this one. My 1st benchmark with THEFOGHEAD. We knew where it was once we clear the water. Took my picture but we may have to get a better one, this didn't come out too clear, but wanted to get posted, at least.

[Photos:]
photoThe Benchmark
I'll try to get a better one, but here's the best for now.

Was out with the CacheClan on our way home from work, when we did this one.We didn't have the coordinates for this we only used the Mapquest map and the previous log.
When we got to the site, we pretty much figured out where we thought it was. Our only problem was that this hole in front of us had a big orange circle around it and the hole it was in was filled with water. So we called our friend MotorBug and got the coordinates( just to be sure) than I found a cup and started scooping water out of the hole until we could see the benchmark. We then took a picture (which will be coming up on the CacheClans log) and we were, off.

Thefogheads

P.S. Thank you MotorBug!

Found this one pretty easily. There was a bright pink surveey marker nearby along with a bright pink circle painted around the benchmark. The cover was missing, but other than that it was in good shape.

[Photos:]
photoBenchmark
Bright pink circle around the benchmark.

Found it with Dad. Catching up now that I have my own account.

Documented History (by the NGS)

01/01/1992 by CA-085 (MONUMENTED)
DESCRIBED BY SANTA CLARA COUNTY CALIFORNIA 1992 (JLP) THE STATION IS LOCATED ON THE CAMPUS OF MISSION COLLEGE IN THE CITY OF SUNNYVALE NEAR THE JUNCTION OF U.S. HIGHWAY 101 AND THE LAWRENCE EXPRESSWAY (COUNTY ROAD G2). TO REACH THE STATION FROM THE JUNCTION OF U.S. HIGHWAY 101 AND INTERSTATE HIGHWAY 880 IN THE CITY OF SAN JOSE, GO NORTH ON HIGHWAY 101 FOR 5.2 MI (8.4 KM) TO THE LAWRENCE EXPRESSWAY EXIT NORTH. TAKE THE OFF-RAMP NORTHWEST AND THEN NORTH AND MERGE WITH THE LAWRENCE EXPRESSWAY. CONTINUE NORTH ON LAWRENCE EXPRESSWAY FOR 0.1 MI (0.2 KM) TO THE INTERSECTION WITH LAKEWOOD DRIVE ON THE LEFT AND BRIDGEWOOD WAY ON THE RIGHT. TURN RIGHT ON BRIDGEWOOD WAY AND IMMEDIATELY TURN RIGHT AGAIN AND GO SOUTHEAST ON WILDWOOD AVENUE FOR 0.8 MI (1.3 KM) TO THE INTERSECTION WITH MISSION COLLEGE BOULEVARD AND THE STATION ON THE LEFT. THE STATION IS LOCATED IN THE NORTHWEST CORNER OF THE INTERSECTION OF WILDWOOD AVENUE AND MISSION COLLEGE BOULEVARD. THE STATION IS A 2.5 INCH SANTA CLARA COUNTY SURVEYOR ALUMINUM DISK INSIDE A 6 INCH ALUMINUM ACCESS COVER FLUSH WITH THE GROUND, 124.1 FT (37.8 M) WEST OF AND ACROSS THE STREET FROM A LIGHT POLE AT THE NORTHEAST CORNER OF MISSION COLLEGE BOULEVARD AND WILDWOOD DRIVE, 83.5 FT (25.5 M) EAST OF A SANTA CLARA VALLEY WATER DISTRICT DISK STAMPED BM-79 AT THE WEST END OF THE CONCRETE HEADWALL OF CALABAZAS CREEK BRIDGE, 69.0 FT (21.0 M) WEST OF THE CENTERLINE OF MISSION COLLEGE BOULEVARD, 46.5 FT (14.2 M) NORTH OF THE CENTERLINE OF WILDWOOD DRIVE, 9.0 FT (2.7 M) SOUTH OF A 4 FT (1.2 M) HIGH CHAIN LINK FENCE AND 2.0 FT (0.6 M) SOUTH OF A FIBERGLASS WITNESS POST. THE DISK IS 0.25 FT (0.08 M) BELOW THE ACCESS COVER AND THE ROD IS DRIVEN TO REFUSAL AT A DEPTH OF 42 FT (12.8 M) . THIS STATION WAS OCCUPIED AS PART OF A CALIFORNIA HIGH PRECISION GEODETIC NETWORK (HPGN) DENSIFICATION SURVEY.
10/22/1993 by CADT (GOOD)
RECOVERY NOTE BY CALTRANS 1993 (DAN) THE STATION WAS RECOVERED AS DESCRIBED.

Control Text

  • The horizontal coordinates were established by GPS observations and adjusted by the National Geodetic Survey in September 1994. The horizontal coordinates are valid at the epoch date displayed above. The epoch date for horizontal control is a decimal equivalence of Year/Month/Day.
  • The orthometric height was determined by GPS observations and a high-resolution geoid model.
  • The X, Y, and Z were computed from the position and the ellipsoidal ht.
  • The Laplace correction was computed from DEFLEC99 derived deflections.
  • The ellipsoidal height was determined by GPS observations and is referenced to NAD 83.
  • The geoid height was determined by GEOID99.

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