Last month, the Duluth News Tribune reported that a large concrete pillar reinforced by timber had disappeared into Lake Superior from its original site at a local structure at Canal Park. Though it is unknown when exactly it vanished, at the time the source said that waves and bad weather may have combined to send the pillar away from the mausoleum where it normally stood.
One local diver, Jim Richardson, called the disappearance inevitable, given the way the column was positioned in the water and the slow erosion over time. It dates back to the early twentieth century, where it was originally part of an unloading dock structure in a place called "the cribs."
However, the same news source now says the pillar has been located, thanks to local use of an ROV. The St. Louis County Rescue Squad deployed the device under the frozen lake and recorded video of the operation, which clearly shows the wooden supports within the concrete where the pillar has been separated.
In the original Tribune article on the pillar's discovery, Richardson described the way the water had impacted it over time.
"The column was composed of timbers sheathed in concrete but much of the concrete below water level was eroded away, leaving bare wood," he said. In addition to being an important discovery, this column has also functioned as a training site for ROV use for the team and a way to assess possible safety hazards.
ROV insurance gives operators protections around their work and helps prepare them for extensive operations. This could be true for searches that include possibly dangerous sites that have become less stable over time, so make sure that there is insurance consideration for any undertakings in hazardous areas.