2014-11-29

GT1321 - S 1036

Found GT1321 in great condition.  At least, it seemed to be in great condition.  It was stable, and in the correct general location, however, the witness post was loose; the result of farming activities, or an automobile accident.  That's not much of an issue for the mark, however.  It looked as of the adjacent power pole had possibly been relocated, though, as it was relatively new.  That was of interest to me.  The described pole was 2 feet southeast of the mark; the new one 1.5 feet east.  These measurements were from the mark to the center line of the pole.  The side of the pole was only inches from the side of the concrete monument setting.  The augers used to set power poles in the ground could easily dislodge a benchmark setting.  While GT1321 looked to be in great condition, its vertical position may have been compromised.  It would take some high precision survey equipment - higher precision than the hand held GPSr I had with me - to correctly determine if the mark was, in fact, stable.

As a benchmark hunter, I'm calling it a find.  As a surveyor, I'd be cautious.
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Published details for Benchmark: GT1321
N 36° 31.900
W 119° 50.700 (NAD 83)
Altitude: 240.1
Coordinates may not be exact. Altitude is VERTCON and location is SCALED. (more info)

Location: In FRESNO county, CA View Original Datasheet
Designation: S 1036
Marker Type: bench mark disk
Setting: set into the top of a round concrete monument
Stability: May hold, but of type commonly subject to surface motion.

Documented History (by the NGS)
01/01/1959 by CGS (MONUMENTED)
DESCRIBED BY COAST AND GEODETIC SURVEY 1959 1 MI SW FROM CARUTHERS. 0.55 MILE SOUTHWEST ALONG TAHOE STREET FROM THE POST OFFICE AT CARUTHERS, THENCE 0.25 MILE WEST ALONG CLEMENCEAU AVENUE, THENCE 0.25 MILE SOUTH ALONG MARKS AVENUE, 38 FEET SOUTHWEST OF THE CENTER OF THE INTERSECTION OF KAMM AVENUE, 27 FEET WEST OF THE CENTER LINE OF MARKS AVENUE, 26 FEET SOUTH OF THE CENTER LINE OF KAMM AVENUE, 2 FEET NORTHWEST OF POWER POLE 4126, 1.1 FEET SOUTHEAST OF A POST SUPPORTING A STOP SIGN, 2.3 FEET SOUTHWEST OF A WITNESS POST, ABOUT LEVEL WITH THE AVENUES, AND SET IN THE TOP OF A CONCRETE POST PROJECTING 0.2 FOOT ABOVE THE GROUND.

Found details for Benchmark: GT1321
N 36° 31.955 W 119° 50.725
GT1321 was found at 10:15, 29 November 2014.

The mark was found generally as described and in good condition. Distances to the center lines of the roads are adequate, however the power pole described has been replaced, and the stop sign and witness post have been moved.

The mark was found to be 1 foot southeast of a of a wooden witness post painted white labeled "CO BM"; 9 feet southeast of a street sign with a stop sign; and 1.5 feet westerly of a relatively new power pole with overhead lines going in four cardinal directions.

WGS84 coordinates found by 4 minute occupation with 8 strong satellites and 2 WAAS satellites.
GT1321 "S1036 1959" - Benchmark detail.
GT1321 "S1036 1959" - Benchmark and GPSr.
GT1321 "S1036 1959" - Benchmark, witness post, and GPSr.
GT1321 "S1036 1959" - Benchmark and witness post.
GT1321 "S1036 1959" - Benchmark setting.  View north up Marks Avenue, across Kamm Avenue.
GT1321 "S1036 1959" - Benchmark setting.  View east across Marks Avenue, along Kamm Avenue.
GT1321 "S1036 1959" - Benchmark setting.  View south down Marks Avenue.
GT1321 "S1036 1959" - Benchmark setting.  View west along Kamm Avenue, from Marks Avenue.
GT1321 "S1036 1959" - Benchmark location at the southwest corner of Marks & Kamm, Caruthers, Fresno County, Ca.

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