Details for Benchmark: HS3048
N 37° 21.900 W 121° 49.667 (NAD 83)
Coordinates may not be exact. Altitude is VERTCON and location is SCALED. (more info)
- In SANTA CLARA county, CA View Original Datasheet
- H 176 2605 CAGS
- Marker Type:
- survey disk
- light structures
- Mark of questionable or unknown stability.
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||Nazgul couldn't find HS3048
DNF, probably destroyed when this corner and the one across Alum Rock were rebuilt several years ago. The south corner has also been rebuilt with a new library IIRC. There are three culverts with drains here but no sign of a disk at any of them.
Documented History (by the NGS)
|01/01/1934 by CAGS (MONUMENTED)
|01/01/1954 by NGS (GOOD)
|DESCRIBED BY NATIONAL GEODETIC SURVEY 1954
AT ALUM ROCK. AT ALUM ROCK, AT THE INTERSECTION OF ALUM ROCK AVENUE AND WHITE ROAD, IN THE TOP OF THE CONCRETE CURB OF A MANHOLE, 57.2 FEET SOUTHEAST OF THE CENTER LINE OF THE AVENUE, 19.3 FEET SOUTHWEST OF THE CENTER LINE OF THE ROAD, 28.7 FEET NORTH OF THE NORTH CORNER OF ALUM ROCK PHARMACY, 1.6 FEET WEST OF THE WEST CORNER OF A CAST IRON GRATE OVER A DRAIN, 0.2 FOOT SOUTHEAST OF THE SOUTHEAST SIDE OF A CAST IRON COVER OF A MANHOLE, AND ABOUT LEVEL WITH THE ROAD. NOTE-- THIS MARK WAS REPORTED DESTROYED ON LITHO LIST DATE SEPTEMBER 27, 1949. EVIDENTLY IT WAS RESET BY SOME OTHER ORGINAZATION. THE MANHOLE WAS CONSIDERED A CULVERT IN THE OLD DESCRIPTION.
- The horizontal coordinates were scaled from a topographic map and have an estimated accuracy of +/- 6 seconds.
- The NAVD 88 height was computed by applying the VERTCON shift value to the NGVD 29 height (displayed under SUPERSEDED SURVEY CONTROL.) The vertical order pertains to the superseded datum.
- The geoid height was determined by GEOID99.