Details for Benchmark: HS4130
N 37° 42.283 W 121° 43.967 (NAD 83)
Coordinates may not be exact. Altitude is VERTCON and location is SCALED. (more info)
- In ALAMEDA county, CA View Original Datasheet
- F 1259
- Marker Type:
- bench mark disk
- massive structures with deep foundations
- Most reliable and expected to hold position/elevation well.
Benchmarks may be on private property or in dangerous locations. Obey local laws. By using the services on Geocaching.com you agree to this disclaimer.
Documented History (by the NGS)
|01/01/1974 by NGS (MONUMENTED)
|DESCRIBED BY NATIONAL GEODETIC SURVEY 1974
0.7 KM (0.45 MI) NE FROM LIVERMORE. 0.45 MILES NORTHEAST ALONG INTERSTATE HIGHWAY 580 FROM THE STATE HIGHWAY 84 (FIRST STREET) OVERPASS IN LIVERMORE, AT THE CROSSING OF A STEEL TOWER POWERLINE, 148.5 FEET SOUTHEAST OF THE SOUTHEAST MOST CENTERLINE OF THE EAST BOUND HIGHWAY LANES, 59.5 FEET SOUTHEAST OF THE CENTERLINE OF A FRONTAGE ROAD, IN THE TOP OF THE SOUTHWEST SIDE OF THE CONCRETE FOUNDATION FOR THE SOUTHWEST STEEL LEG OF A TOWER, 27 FEET NORTHEAST OF THE CENTERLINE OF A DIRT ROAD LEADING SOUTHEAST, 0.3 FOOT SOUTHWEST OF THE SOUTHWEST STEEL TOWER LEG, AND ABOUT 1.5 FEET HIGHER THAN 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- The NAVD 88 height was computed by applying the VERTCON shift value to the NGVD 29 height (displayed under SUPERSEDED SURVEY CONTROL.) The vertical order pertains to the superseded datum.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.