USGS
Bench Mark
"DW 5240"

ca. 1898

Jerry Penry
May 13, 2011

The copper bolts placed by USGS during the late 1890's in the Black Hills are among the most elusive monuments to find. The original description for "DW 5240" stated that this bench mark was in the center of a rock cut along the west side (northerly) side of the railroad tracks and six inches above the tracks. A distance of 235 feet was given from the southwest end of Bridge 42. Today the tracks are gone and the former roadbed is part of the Mickelson Trail. The distance was measured from the bridge. Two metal detectors were used by Kurt Luebke and Jerry Penry and a search was made all along both sides of the rock cut, but nothing was found. We assume that the rock cut was possibly widened many years ago and the copper bolt bench mark was removed. A search was also made on the loose rocks along the slopes of a fill section as the end of the cut, but no success. The location is approximately four miles south-southwest of Hill City, South Dakota.

The cut section through the rock where the bench mark was located.

The approximate location where the marker should have been located by measuring from the bridge.

The slope at the east end of the cut where the loose rocks were checked with a metal detector.

A recovered old tie plate with two holes for spikes and four pointed tabs on the bottom.

The original USGS quad sheet showing the bench mark location.

Other Deadwood Datum Bench Marks

© Jerry Penry 2011