Water Studies Institute surveys Bay bottom
July 21, 2009
TRAVERSE CITY — Northwestern Michigan College’s Water Studies Institute is spearheading the first effort to map the bottom of Grand Traverse Bay in 80 years, an endeavor which already is expected to lead to the first public pictures of a 1980 shipwreck near Suttons Bay.
Assisted by Michigan Sea Grant, NMC is conducting advanced hydrographic surveys of both east and west arms of Grand Traverse Bay and northern Lake Michigan this summer and again in 2010. The first phase of underwater research, conducted with side-scan sonar equipment aboard the NMC research vessel Northwestern, is now underway and will continue through Aug. 10. To see pictures, visit nmc.edu/water.
Since existing data dates to the 1920s, the survey project will provide important updated and expanded information with multiple applications, including environmental impact assessments, commercial navigation charts and supporting fisheries.
“The Great Lakes continue to be challenged by both natural and human-induced stressors, including the changing climate, continued introductions of non-native invasive species and lake level fluctuations,” said Hans Van Sumeren, director of the Water Studies Institute. “These stressors have dramatically altered the Great Lakes ecosystem, our near shore waters and nearly all of our navigable waters and harbors, but existing data is outdated and does not accurately reflect how the ecosystem has changed.”
The survey equipment is being donated at no cost to NMC by Kongsberg Underwater Technology, Inc., a Norwegian company that is a world leader in its industry. Van Sumeren said the equipment will collect imagery from the bottom of the bay to 1 inch resolution. The data will be collected in a 1,000-foot swath from the moving Northwestern.
“Basically it’s a motion picture of the bottom. That’s the kind of resolution we’ll get,” Van Sumeren said. He added that the technology will provide much more accurate depth measurements than currently exist.
“The technology has advanced so much that we probably don’t know the true depths of our lake in certain positions,” he said.
In the first week of surveying, researchers believe they have already pinpointed the location of one known but to date unphotographed shipwreck, that of the Lauren Castle tugboat. She sank Nov. 5, 1980 off Lee Point near Suttons Bay, in water more than 400 feet deep. The sonar detected an object consistent with the wreck’s coordinates this week, Van Sumeren said. A submersible remote operated vehicle equipped with a camera will be sent down to investigate further.
The Great Lakes Hydrographic Survey Project will provide key scientific information and facilitate technical competencies and educational opportunities for NMC students. The project will constitute a major portion of the curriculum of NMC’s new Freshwater Studies degree, the first such associate degree program in the nation. Students will develop case studies and field projects based on the survey data, Van Sumeren said.
In addition, cadets in NMC’s Great Lakes Maritime Academy will have the unique opportunity for hands-on training with the hydrographic survey technology.
The data will be shared with governmental agencies like the National Oceanic and Atmospheric Administration. Potentially it could serve as a template project for a hydrographic survey of all five Great Lakes, Van Sumeren said.
“The idea is that the information will be shared,” Van Sumeren said. “What we want this to be is the launching pad for knowledge and appreciation for what this means for our waters.”
For more information:
Hans Van Sumeren