Benchmarks

The purpose of this page is to provide information about the benchmark. This information is important for the re-establishment of a gage site at a certain location, in the event the gage is ever destroyed.

Elevation of Gage Zero: This is the elevation (in feet) above mean sea level, that the gage will read zero.

Leveling Agency and Date: Enter the name of the agency responsible for the last leveling measurement, and the date of the last measurement.

Rating Agency and Date: If a stage/discharge rating is produced for a station, enter the name of the rating agency and the date.

Vertical Datum: This is the reference datum used to define gage zero. This is usually the National Geodetic Vertical Datum of 1929 (NGVD), or the North American Vertical Datum of 1988 (NAVD). The U.S. Engineering Datum (USED) is another reference datum, but is rarely used.

Checkbar: This is filled out if there is a wire weight stream gage. The checkbar is the reading (in feet) of the wire weight stream gage checkbar above the zero datum.