Details for Benchmark: MB1709
N 41° 56.917 W 080° 30.267 (NAD 83)
Coordinates may not be exact. Altitude is ADJUSTED and location is SCALED. (more info)
- In ERIE county, PA View Original Datasheet
- P 363
- Marker Type:
- metal rod
- stainless steel rod
- Probably hold position/elevation well.
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Documented History (by the NGS)
|01/01/1981 by NGS (MONUMENTED)
|DESCRIBED BY NATIONAL GEODETIC SURVEY 1981
2.7 KM (1.7 MI) WSW FROM WEST SPRINGFIELD. 2.7 KILOMETERS (1.7 MILES) WEST-SOUTHWEST ALONG US HIGHWAY 20 FROM THE US POST OFFICE IN WEST SPRINGFIELD TO THE MARK ON THE RIGHT, THE MARK IS IN THE SOUTHEAST CORNER OF THE FRONT LAWN OF A SINGLE STORY WOOD FRAME HOUSE, NUMBER ROUTE 1 414, OWNED AT THIS TIME BY MR. HARRY SMITH, 1.3 KILOMETERS (0.8 MILE) EAST OF THE OHIO AND PENNSYLVANIA STATE LINE, 11.27 METERS (37.0 FEET) NORTH OF THE CENTER LINE OF THE HIGHWAY, 13.41 METERS (44.0 FEET) EAST OF THE CENTER OF THE PAVED DRIVEWAY OF THE HOUSE, 9.61 METERS (31.5 FEET) SOUTHEAST OF THE SOUTHEAST CORNER OF THE HOUSE AND 0.48 METER (1.6 FEET) NORTH OF POWER POLE NUMBER 25226,88 WITH POWER LINES CROSSING THE HIGHWAY. THE MARK IS ABOVE LEVEL WITH THE HIGHWAY.
|01/01/1988 by USPSQD (GOOD)
|RECOVERY NOTE BY US POWER SQUADRON 1988 (GM)
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.