By Chris Sabick, Director of Archaeology
This month, our underwater archaeology team – including myself, archaeologist Cherilyn Gilligan, dive master Ron Adams, and occasionally Willa the dog – has been conducting end-of-season site inspections on the Vermont Underwater Historic Preserve sites.
What is the Vermont Underwater Historic Preserve? Operated by the Vermont Division of Historic Preservation and managed by Lake Champlain Maritime Museum, the preserve was initiated to protect the lake’s historic shipwrecks and provide public access for divers in a manner that is safer for the diver and the shipwreck. The recreational diving season runs from May to October and as the stewards of these sites, our archaeology team opens and closes the wrecks each year. An important part of this work is the end-of-season site inspection that our team conducts every year in October.
The site inspection involves assessing any changes in condition that a wreck site may have suffered over the course of the previous year. Condition changes could stem from zebra mussel damage, diver impacts, or environmental conditions. In addition to observing the wreck itself, we also assess the condition of the mooring system, travel line, and signage that are located at each site and determining what will need to be replaced or repaired at the start of next season.
Regular site inspections are important because they allow us as archaeologists to monitor the condition of the wreck sites over time. This also helps us to make informed planning decisions for the Underwater Historic Preserve from a set base of knowledge. Inspections also allow us to ensure that the infrastructure of each site is properly maintained and that we are providing the safest possible access to these historic treasures.
Additionally, we got the chance to put our photogrammetry skills and cameras to the test during our site inspections this month. Photogrammetry is the practice of using many overlapping photographs to create scaled and sometimes geo-referenced 3-D models, maps, and other imagery. This technology has many applications in the field of archaeology, and is especially useful for us as we can use it to capture data from underwater sites and construct 3-D models – digitally and potentially even physically – to share these shipwrecks with a wider public audience beyond the dive community.
While conducting the inspection dive of the Sloop Island Canal Boat we were able to capture the data necessary to create a 3-D model of a portion of the deck, specifically forward of the vessel’s cabin where the ship’s wheel and steering mechanism are located – check it out below. While this model displays only a piece of this wreck site, we hope to gather the data to make models of entire vessels next season.