Mapping the Great Lakes: Proposed legislation would fund lakebed exploration

KALAMAZOO, Mich. — A proposed bill in the US House would provide funding to map the lakebeds of the Great Lakes, the world's largest freshwater system.

The legislation would direct the National Oceanic and Atmospheric Administration to conduct high-resolution bathymetric mapping of the lakebeds of the Great Lakes and authorize $200 million in appropriations.

Currently stalled in committee, the bipartisan Great Lakes Mapping Act was introduced by Michigan Reps. Lisa McClain and Debbie Dingell in mid-January. The bill is cosponsored by a total of 18 lawmakers representing Michigan, Minnesota, Wisconsin, New York, Ohio and Illinois.

“Investing in comprehensive Great Lakes exploration will offer Michigan and the U.S. an enhanced look at what these bodies of water offer and bring forth a new chapter of success and prosperity to the Great Lakes economy and beyond," McClain said in a release.

Bathymetric maps show a water body's depth and underwater features. They're similar in appearance to topographic maps, which show elevation and various features on land. Today, only about 10 to 15% of the Great Lakes have been mapped in high resolution.

"We haven't really ever explored them fully, in high resolution," said Tim Kearns, chief information officer for the Great Lakes Observing System, or GLOS. "It would give us the means to fully survey the Great Lakes using sonar technologies in high resolution on both sides of the border."

Based in Ann Arbor, GLOS is one of 11 regional offices that make up the NOAA-funded Integrated Ocean Observing System. NOAA would work with consulting bodies and regional coastal observing systems to map the lakebeds an make all data available to the public.

"We don't have many areas that are truly unexplored anymore, this is the final frontier for underwater mapping in the United States, and in North America for that matter," Kearns said. "We're looking forward to being able to not only document it, but understand what's down there and make new discoveries."

Lakebed data would be collected by various government and private vessels, crewed and uncrewed, outfitted with sonar scanning technology. The last time the Great Lakes were explored using sonar was in the 1950s, 60s and 70s, but the resolution was much lower than what is possible today.

Decades old low-resolution data has spacing about 500 meters between points. Modern high-density sonar data allows for the visualization of objects as small as pipelines, cables, shipwrecks, and boulders.

The lake floor is a dynamic, changing environment, which has implications for underwater infrastructure. "Being able to understand and see the detail of these pipelines and cables and other things that are down there, whether they be cars, or shipwrecks or plane crashes is really important for being able to document and protect them," Kearns said.

According to Kearns, a report by GLOS found the task of mapping the Great Lakes lakebed could be accomplished in approximately 8 years with proper funding.

The Great Lakes generate a GDP of $6 trillion and supports over 51 million jobs. As a critical shipping lifeline, it's estimated 200 million tons of cargo is shipped through the Great Lakes every year.

The effort to explore the bottoms of the Great Lakes has been in the works for several years. GLOS has been instrumental in the Lakebed 2030 initiative, a coalition of researchers, government entities, private individuals and organizations with the shared goal of mapping and exploring the bottom of the Great Lakes.

GLOS has partnered with Orange Force Marine to help develop a system of crowd sourcing bathymetry data as well. Data loggers can be attached to even a basic fish finder, which is then sent to GLOS to compile and access.

The House is in recess until Feb. 28, 2024. As of now the Great Lakes Mapping Act is still awaiting discussion in committee. The bill can be viewed in its entirety via Congress.gov.