Mapping the vast underwater realms of the Great Lakes is gaining momentum as scientists and lawmakers unite to address what lies beneath these massive bodies of freshwater. While the surface of the lakes has been prominent throughout history—supporting various ecosystems, fisheries, and recreational activities—the depths remain largely uncharted. With this renewed effort, advocates are hopeful for enhanced safety for shipping and fishing operations, as well as greater insights for environmental management.
At the forefront of this initiative is Jennifer Boehme, the executive director of the Great Lakes Observing System (GLOS). Having spent her childhood searching Florida beaches for treasures, Boehme now seeks to map the bottom of the Great Lakes with the same enthusiasm. Her organization aims to chart every meter of the lakebed, which could help identify everything from shipwrecks to underwater infrastructures.
“One of the things that's truly motivating is the potential for discovery,” Boehme remarked. “There is so much we still don’t know about the lakes. We actually know more about the surfaces of the moon than we do about the underwater landscapes of the Great Lakes.” Her emphasis on exploration highlights the importance of this initiative for both scientific and public interest.
Currently, fewer than 15% of the Great Lakes’ bottoms have been accurately mapped, leaving significant gaps in our knowledge. The last substantial mapping occurred back in the 1970s and relied heavily on single-beam sonar technology, which produced maps of poor resolution. These older maps primarily covered coastal areas, leading to substantial underrepresentation of the vast underwater features, including potential hazards for shipping lanes and fishing zones.
This renewed drive for comprehensive mapping of the Great Lakes was bolstered by advances in technology, including multibeam sonar and laser imaging techniques. Multibeam sonar, for example, sends out multiple sound waves as opposed to one, allowing scientists to capture detailed images of the lakebed. Laser imaging, on the other hand, utilizes aircraft to map the terrain above water, creating three-dimensional visuals of underwater topography.
Steven Murawski, a respected biological oceanographer from the University of South Florida, supports the mapping efforts. Murawski articulates the myriad benefits of pinpointing the underwater features. “High-resolution maps are invaluable,” he explained, noting how they can guide navigational safety, inform predictions about shifting underwater terrains, and assist local governments and insurance companies gauge the impacts of storm surges and flooding associated with climate change.
Given the scale of the Great Lakes—covering about 94,250 square miles—this is no small task. Depths vary significantly, from around 210 feet in Lake Erie to over 1,300 feet at specific locations within Lake Superior. The project also hopes to identify hundreds of shipwrecks and remnants of ancient coastal civilizations scattered throughout the lakes. Some estimates suggest the Great Lakes may contain around 6,000 wrecks waiting to be documented.
Among the key legislative supporters are two congressional representatives from Michigan—Republican Lisa McClain and Democrat Debbie Dingell. They have introduced a proposal to allocate $200 million for mapping the lake bottoms by 2030. “We, as representatives, need to take the exploration and discovery of our Great Lakes seriously,” McClain stated during discussions at the House subcommittee. The bipartisan nature of this effort marks significant progress toward drawing attention to the needs of the Great Lakes' preservation and exploration.
Despite increasing support from the scientific community and lawmakers alike, challenges persist. Delegate Cliff Bentz from Oregon commented during the congressional meeting about the necessity of articulately conveying the greater benefits of lake mapping beyond just tourism and discovering shipwrecks. His remarks reflect the need for demonstrable impact to garner the required governmental funding.
The effort to comprehensively map the Great Lakes will offer substantial benefits to various sectors, including local fisheries and shipping industries, which depend on knowledge of underwater conditions. For example, mapping could provide insight on fish aggregations, enhancing sustainability efforts and improving fishing regulations. Additional information about submerged pipelines and other infrastructures can bolster public safety by ensuring navigators are more aware of potential hazards.
Efforts are underway, but the prospects of the funding bill remain uncertain amid the backdrop of electoral politics. Boehme, though hopeful, questions the bill's traction as election year pressures start to mount. “This research is for the public good,” she affirmed. “Our key is persistence. We need to keep articulately making our case to Congress. Understanding our systems allows us to conserve them more effectively.”
With efforts still on the table for the Great Lakes Bottom Mapping Initiative, many locals are optimistic about the project's potential impacts. Boehme and her team continue to advocate for this invaluable research. On the horizon, the annual conference hosted by GLOS provides opportunities to discuss progress and new technologies for mapping, highlighting the collaborative efforts necessary to make this ambitious task successful.
