Details for Benchmark: HT1858
N 37° 48.217 W 122° 11.467 (NAD 83)
Coordinates may not be exact. Altitude is VERTCON and location is SCALED. (more info)
- In ALAMEDA county, CA View Original Datasheet
- Q 1253
- Marker Type:
- bench mark disk
- light structures
- Mark of questionable or unknown stability.
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Documented History (by the NGS)
|01/01/1974 by NGS (MONUMENTED)
|DESCRIBED BY NATIONAL GEODETIC SURVEY 1974
2.7 KM (1.70 MI) NORTH FROM OAKLAND. 1.7 MILES NORTH ALONG STATE HIGHWAY 13 FROM THE JUNCTION OF INTERSTATE HIGHWAY 580 IN OAKLAND, 0.55 MILES SOUTHEAST OF THE CROSSING OF LINCOLN AVENUE, 0.05 MILES SOUTHEAST OF HIGHWAY PADDLE BOARD 13 ALA 600, IN TOP OF THE SOUTH CORNER OF A 4X4 FOOT CONCRETE BOX CATCH BASIN WITH A METAL GRATE, 20 FEET SOUTHWEST OF THE CENTERLINE OF THE SOUTH BOUND LANES OF THE HIGHWAY, 0.4 FOOT NORTHEAST OF A ASPHALT CURB, 0.3 FOOT NORTH OF THE SOUTH CORNER OF THE CATCH BASIN, 0.9 FOOT SOUTHEAST OF THE SOUTH CORNER OF THE METAL GRATE, AND ABOUT LEVEL WITH THE HIGHWAY.
- 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- The NAVD 88 height was computed by applying the VERTCON shift value to the NGVD 29 height (displayed under SUPERSEDED SURVEY CONTROL.) The vertical order pertains to the superseded datum.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.