Details for Benchmark: AH5040
N 45° 35.788 W 122° 35.611 (NAD 83)
Coordinates may not be exact. Altitude is VERTCON and location is ADJUSTED. (more info)
- In MULTNOMAH county, OR View Original Datasheet
- Marker Type:
- driven into the ground
- Mark of questionable or unknown stability.
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Documented History (by the NGS)
|01/01/1992 by MGSINC (MONUMENTED)
|DESCRIBED BY MINISTER AND GLAESER 1992 (DRP)
THE STATION, TRAV1, IS LOCATED ALONG THE SOUTH SHORE OF THE COLUMBIA RIVER NEAR THE PORTLAND INTERNATIONAL AIRPORT ALONG THE NORTH SIDE OF MARINE DRIVE APPROXIMATELY 1000 FEET EAST OF THE NORTHERLY EXTENTION OF RUNWAY 2-20. THE STATION IS A 1/2 INCH DIAMETER IRON ROD DRIVEN INTO THE GROUND ALONG THE SOUTH EDGE OF THE PAVED BIKE PATH.
- The horizontal coordinates were established by classical geodetic methods and adjusted by the National Geodetic Survey in November 1998.
- The NAVD 88 height was computed by applying the VERTCON shift value to the NGVD 29 height (displayed under SUPERSEDED SURVEY CONTROL.)
- The Laplace correction was computed from DEFLEC99 derived deflections.
- The geoid height was determined by GEOID99.