Survey benchmarks (like the one pictured) are metal disks set in concrete used to establish absolute positioning. They were often used to measure out property boundaries but with the advancement of technology they been superseded by GPS and laser measuring. This has led many of these disks to fall into disrepair or buried by their natural surroundings. In high school, one of my engineering teachers challenged the class to look for these over school break after learning about surveying in class. Although I was unsuccessful at finding any at the time, I enjoyed that it was like a treasure hunt.
Due to the age and decreasing relevance of benchmarks, before venturing out to find one it was important to research it's location and last known status. This can be done using the NGS Data Explorer, which would allow the user to look for survey marks within a radius of a point. This provides easy access to each mark's datasheet; providing information like PID (point ID), GPS coordinates, site description, date of last recovery, etc. Checking each mark's status then coloring it on a map was very time-consuming. Therefore, I wanted a way to automat the process, allowing me to be more efficient.
It's important to note that government agencies do not check up on these benchmarks regularly, often leaving decades between 'official' sightings. I choose to use the Geocaching site to determine if it has been spotted recently and if there were any pictures attached to the entry. The combination of the NGS api and scraping Geocashing.com provided enough information to determine a value score. The outcome of this process can be exported as a csv, allowing it to be imported into Google Maps for ease-of-use while out in the field looking for benchmarks. The programming language of choice was Python.
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Geocaching retired their benchmark pages in Jan 2023, an updated version of this tool is in the works.