Details for Benchmark: HY1088
N 38° 44.617 W 082° 59.417 (NAD 83)
Coordinates may not be exact. Altitude is ADJUSTED and location is SCALED. (more info)
- In SCIOTO county, OH View Original Datasheet
- A 208
- Marker Type:
- bench mark disk
- massive structures
- Probably hold position/elevation well.
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Documented History (by the NGS)
|01/01/1958 by CGS (MONUMENTED)
|DESCRIBED BY COAST AND GEODETIC SURVEY 1958
0.1 MI S FROM PORTSMOUTH. ABOUT 0.1 MILE SOUTH ALONG THE NORFOLK AND WESTERN RAILWAY FROM THE STATION AT PORTSMOUTH, SET IN THE TOP OF THE SOUTH END OF THE EAST HEADWALL TO A RAILWAY OVERPASS OVER SIXTEENTH STREET, 8 FEET EAST OF THE EAST RAIL OF THE EAST TRACK, 0.3 FEET SOUTH OF THE SOUTH END OF THE EAST GUARD RAIL, ABOUT 1 FOOT ABOVE THE LEVEL OF THE TRACK. NOTE-- THE MARK WAS SET TO REPLACE P 72 WHICH WILL BE DESTROYED BY HIGHWAY CONSTRUCTION.
|01/01/1967 by NGS (GOOD)
|RECOVERY NOTE BY NATIONAL GEODETIC SURVEY 1967
RECOVERED IN GOOD CONDITION.
- 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 June 1991.
- 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.