Feature ArticleRemote Underwater Surveys Of War of 1812 Shipwrecks
DAS model of the Scourge's hull viewed from the port side. This 3D point-cloud data was indispensable for a range of archaeological products, including site plans and 3D reconstructions. (Photo Credit: ASI Group Ltd.)
Early on the morning of August 8, 1813, a violent summer squall sent the United States Navy armed schooners Hamilton and Scourge to the bottom of Lake Ontario, northwest of the mouth of the Niagara River. The schooners were part of an American squadron waiting out the night to do battle with a nearby British Royal Navy squadron. Since the outbreak of the War of 1812 a year earlier, both squadrons had vied for control of the strategically important Lake Ontario. The comparatively small schooners were launched as merchant vessels (the American Diana and British Lord Nelson, respectively) and later pressed into naval service. More than 50 men drowned when the ships sank, and only 16 survived.
Surveying the Wrecks
With advances in marine remote-sensing technologies in the early 1970s, relocating the wrecks became viable. In 1972, a marine remote-sensing search commenced, spearheaded by the Royal Ontario Museum (Toronto, Canada)and research associate Dr. Daniel Nelson. The project drew support from the Canada Centre for Inland Waters (CCIW) in Burlington, Canada. In 1973, a side scan sonar target was identified. During a 1975 follow-up survey, 100-kilohertz side scan sonar images showed two well-preserved wrecks with intact hulls, standing masts and guns still in place on the decks. They were located in Canadian waters 12 kilometers offshore from St. Catharines, Ontario, Canada, 90 meters deep and 460 meters apart in the cold (4° C) and dark shipwreck-preserving waters of Lake Ontario.
In November 1975, the prototype ROV TROV 1 of CCIW was deployed to the wreck, which was later identified as the Hamilton. A series of ambitious sonar mapping and site environmental studies followed in 1978, when CCIW researchers attempted to create georeferenced side scan mosaics and used stationary, bottom-mounted sonar systems to generate scaled wreck-site plans. Additional ROV and submersible dives took place in 1978 (Deep Diving Systems's Sea Scanner), 1980 (Jacques Cousteau's Soucoupe), 1982 (Benthos's RPV-430) and 1990 (Woods Hole Oceanographic Institution's Jason). Collectively, these surveys captured thousands of archaeologically invaluable still images, dozens of hours of video and a limited amount of geomatic data, all of which recorded the schooner's hulls, rigging, fittings, guns, shot and even human remains on the lakebed.
The wrecks became a National Historic Site of Canada in 1976, and ownership of them was transferred from the United States Navy to the City of Hamilton, Ontario, in 1980.
From the late 1970s to the early 1990s, project organizers explored the feasibility of raising one or both of the wrecks. This elaborate plan did not materialize, and by the late 1990s the City of Hamilton was exploring options to present and protect the wrecks in situ. In 2000, it formed a partnership with St. Catharines-based marine engineering company ASI Group Ltd. (ASI) to provide project management and technical services. It also drew underwater archaeological support and advice from Parks Canada's Underwater Archaeology Service (UAS).
About this time came news that technical sport divers had visited the wrecks and had observed invasive mussels on both sites, either zebra mussels (Dreissena polymorpha) or their close relative the quagga mussel (Dreissena bugensis). These mussels had arrived in the Great Lakes from Europe in the 1980s and colonized the wrecks following the 1990 survey (when none were observed).
The advent of both diving visitation and the mussel occupation posed significant site management challenges for the City of Hamilton, and with key partners it launched the Hamilton & Scourge Condition Survey. This aimed to verify the wrecks' conditions compared against previous surveys, assess mussel occupation, improve site geomatic data and explore the wrecks' interiors. Bob Clarke and Darren Keyes of ASI and Jonathan Moore and Ryan Harris of the UAS served as the project's technical and archaeological leads.
In the lead-up to the condition survey, the Canadian Hydrographic Service (CHS) carried out a bathymetric survey of a 1.4-by-1.8-kilometer lakebed study area over and around the wrecks with a Simrad (Horten, Norway) EM 3000 in 2004 and an EM 3002 in 2005. While these shallow-water systems did not generate detailed images of the wrecks, they resulted in 1-to-2-meter absolute bottom positioning accuracy that paid dividends for future work on the sites.
As plans for ROV condition survey dives took shape and efforts to secure a surface platform were underway, the National Water Research Institute of Environment Canada deployed current meters near the sites in 2006. The meters recorded light-transmission profiles to better predict the periods of optimum visibility, given a near-bottom nepheloid layer characterized by suspended particulate.
In April 2007, the UAS completed a side scan sonar survey of the study area from its survey boat Red Bay using an L-3 Klein (Salem, New Hampshire) 3000 dual-frequency (132 and 445 kilohertz) system with an armored tow cable, a 3PS Inc. (Cedar Park, Texas) metering sheave block for layback control, NovAtel Inc. (Calgary, Canada) ProPak mapping-grade Canada-wide differential GPS service (CDGPS) receiver for positioning, and HYPACK Inc. (Middletown, Connecticut) Max for navigation control. Both detailed wreck imaging and mosaic coverage of the study area were completed, with the final mosaic assembled using Chesapeake Technology Inc. (Mountain View, California) SonarWiz software and drawing upon the CHS bathymetric coverage and wreck positioning.
By 2007, the major preparatory steps for a nonintrusive ROV survey of each wreck were complete and the Canadian Navy ship HMCS Kingston had been secured to serve as the survey platform in May 2008. The final step was to create mooring plans for each site, given the necessity to avoid damaging each wreck and its nearby debris fields. Using the side scan sonar mosaic and taking into account the prevailing wind conditions, areas of the lakebed free of features were chosen and cleared with inspection dives using UAS's SeaBotix (San Diego, California) LBV 150 micro-ROV deployed from the CHS survey boat Merlin. A self-imposed 90-meter-diameter exclusion zone was created for mooring gear measured from the center of each wreck. In the days leading up to the survey, the Canadian Coast Guard ship CCGS Griffon precisely deployed three moorings at planned positions for each site.
The inspection mission of 2008 was conducted on a 24-hour basis to maximize the available time on site and utilize the government assets provided. Personnel transfer between shore and the Kingston was provided by the CCGS Cape Storm and ASI using two survey vessels, the ASI Inspector and ASI Surveyor. ASI used their Saab Seaeye (Fareham, England) Falcon ROV configured with their proprietary dual-axis sonar (DAS) system to generate multiple point cloud data sets for each vessel, which were subsequently merged into a comprehensive set. To continue this article please click here.
Jonathan Moore, who has a master's in maritime studies, is a senior underwater archaeologist with Parks Canada's Underwater Archaeology Service, based in Ottawa, Canada. For more than 20 years he has worked on projects throughout Canada and the United Kingdom. His involvement with the Hamilton and Scourge began in 1999, and he served as the licensed underwater archaeologist for the 2007, 2008, 2009 and 2013 surveys.
Bob Clarke (professional engineer and project management professional) has more than 30 years of experience in the marine industry. Currently, as senior operations manager for ASI Group Ltd., based in St. Catharines, Canada, he manages a fleet of ROVs and directs the development of new equipment and technologies to meet customer requirements. Throughout the years, Clarke has written several articles for industry magazines and peer-reviewed articles for technical journals.
Ryan Harris, who has a master's in maritime history and nautical archaeology, is a senior underwater archaeologist with Parks Canada's Underwater Archaeology Service. For 20 years, he has worked on projects throughout Canada and the United States. He was responsible for equipment deployment, data acquisition and data post-processing during the 2007 and 2013 Hamilton and Scourge remote-sensing surveys.