Details for Benchmark: AB8606
N 34° 04.367 W 117° 45.600 (NAD 83)
Coordinates may not be exact. Altitude is ADJUSTED and location is SCALED. (more info)
- In LOS ANGELES county, CA View Original Datasheet
- Marker Type:
- bench mark disk
- massive retaining walls
- Probably hold position/elevation well.
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Documented History (by the NGS)
|01/01/1967 by LACFCD (MONUMENTED)
|06/17/1994 by MWDSC (GOOD)
|DESCRIBED BY METRO WATER DISTR SO. CALIFORNIA 1994 (DEL)
POMONA, NEAR THE INTERSECTION OF WHITE AV. AND VAL VISTA ST. AT THE SOUTHWEST CORNER OF FLOOD CONTROL BRIDGE, 30 FEET (9.1 M) SOUTH OF VAL VISTA ST. AND 135 FEET (41.1 M) WEST OF WHITE AV. FOUND A 2 INCH DOMED HEAD LACFCD BRASS DISK STAMPED BM 104.03015 1967 IN TOP OF WESTERLY END OF CONCRETE HEADWALL OVER SAN JOSE CREEK FLOOD CONTROL CHANNEL. REFERENCE MWD FB 4038 01 082.
- The horizontal coordinates were scaled from a topographic map and have an estimated accuracy of +/- 6 seconds.
- The orthometric height was determined by differential leveling and adjusted by the National Geodetic Survey in February 1997.
- The geoid height was determined by GEOID99.
- The dynamic height is computed by dividing the NAVD 88 geopotential number by the normal gravity value computed on the Geodetic Reference System of 1980 (GRS 80) ellipsoid at 45 degrees latitude (G = 980.6199 gals.).
- The modeled gravity was interpolated from observed gravity values.