The National Oceanic and Atmospheric Administration (NOAA) has been working to collect new mapping data on Lake Superior since 2020. This survey is part of a large effort to update the mapping of the coastal and nearshore water of the Great Lakes. The project has been made possible by funding through the Great Lakes Restoration Initiative.

During the multiyear effort, the crew of the NOAA survey vessel “Dorothy” has been tasked with collecting data for 35 square nautical miles of Lake Superior.

“This portion of Lake Superior has not been mapped since 1981 and 1982,” explained Brandon Krumwiede with the NOAA Office for Coastal Management. “Prior to the early 1980s, the only detailed survey was completed in 1943. The new data helps to provide a greater level of detail than what we previously had access to.”

The new details come from the technological advancements in the decades since the last survey. In the 1980s, sounding of the lake was done using a single beam method. A single beam was able to collect a single sounding reading about every second or less. Now, the “Dorothy” vessel is equipped with a multibeam echosounder.

John Gray, the acting lead hydrographer onboard the vessel, explained that the multibeam echosounder allows them to gather significantly more readings in the same amount of time.

“These are big technology upgrades over in the charting world,” explained Gray. “So, where a single beam can collect one sounding maybe every second or less, we can collect thousands of soundings in a second.”

Gray and the rest of the crew of the “Dorothy” came up from Gulf Port, Mississippi during summer 2024 to continue their efforts. During their normal functions, the crew is normally seen responding to coastal disasters, but they were happy to be a part of the data-collecting process to help create new charts for the lake.

“In hydrography, we have a big term – we say map once and used many times really for any science,” explained Gray. “If you collect data, whether it’s water quality samples, fish catches, or anything else underlying that data is a map.”

Gray continued that the primary mission in the data collection is to assist with safety and navigation, but as Krumwiede explained, the data has even more uses than that.

“We have seen a lot more features out there that previously went unmapped and, so, those types of features allow us to understand fish movement [and] what type of habitat they’re preferring,” explained Krumwiede. “Also, that information feeds into a lot of the various models that NOAA and other federal agencies use to model things like coastal inundation or flooding along our coast.”

The data also helps track invasive species in the lake.

“At the moment, we do know zebra mussels have been found in small locations within Lake Superior, [but] it is hard at the moment to determine the full-scale extent or potential extent without knowing just how much area could be affected or inhabited by these invasive species,” said Krumwiede. “The new data collected can help to identify where we might see initial colonization and where it could spread from and where it could spread to next.”

During a daily excursion, the crew of the vessel can collect terabytes of data. John Gray explained that as the data comes in, they are paying close attention.

“We’re doing QA, quality assurance, in real-time, because we’re only out here once and so every minute we’re out here, we have to make sure we’re collecting exactly the right data and not wasting any time,” said Gray. “It’s a big job and so efficiency is key.”

Krumwiede also shared his thoughts on when the public can expect to see the results of the data collected.

“It is a lot of data that is being collected processed and reviewed. Right now, we are averaging about 1 to 2 years after data is initially collected in making it publicly available.

NOAA crews will return to Lake Superior in the summer of 2025. The next survey will collect data in some of the Great Lake’s deeper waters.

“We just hope it raises awareness,” said Krumwiede when asked about his hope for the project. “I think, for me personally,[it] is the appreciation that there is a lot yet to be discovered here in our own backyard. We don’t have to necessarily go to Mars or the moon, but right here there’s a lot of opportunity for the next generation to explore and discover the Great Lakes.”