DETROIT — A team of nonscientists may have inadvertently confirmed the most important finding in Great Lakes archaeology in at least a decade.
The group, made up mostly of Native American tribal citizens, utilized a remote-operated underwater vehicle in the Straits of Mackinac to take a look at Enbridge's Line 5 oil and natural gas pipelines on the lake bottom. But among the things they found were stones they say appear arranged in circular and linear patterns on the lake floor.
If that was done by the hands of humans, it occurred when the Straits area, which divides Michigan's peninsulas, was last above water — near the end of the last Ice Age, about 10,000 years ago.
"We didn't expect to find this — it was really just amazing," said Andrea Pierce, a 56-year-old Ypsilanti resident and citizen of the Little Traverse Bay Bands of Odawa Indians, who was one of four women who drove the project to inspect the Straits bottom.
"My question is, who knew they were there?"
The finding seems to correlate with a University of Michigan archaeologist's 2009 discovery of similar stone formations under water in Lake Huron, near Alpena, Michigan, also believed to be from an ancient, Ice Age-era culture. That professor, John O'Shea, told state officials in February that a consultant, hired by Enbridge to explore the area of its proposed Straits tunnel pipeline project, relayed to O'Shea that he had seen similar rock formations in the Straits.
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"The technician assigned to the job was told only to consider shipwrecks," O'Shea wrote in a Feb. 12, 2020, letter to deputy state historic preservation officer Martha MacFarlane-Faes.
"When the technician noticed linear stone alignments of the type documented in Lake Huron, he was told to ignore them. When he asked permission to consult with me about their potential cultural origin, his request was again denied. He was subsequently removed from the project and was not allowed to see the final report."
SEARCH Inc. did not return messages left over multiple days. The Newberry, Florida-based cultural resource management company was contracted by Enbridge for assessment of cultural resources on the Straits bottom as part of Enbridge's Line 5 tunnel project.
A report by Enbridge to the state last year noted that of 32 "acoustical contacts" it found on the Straits floor near the tunnel project area, "none ... were determined likely to represent a submerged cultural resource."
Enbridge spokesman Ryan Duffy confirmed SEARCH was commissioned to conduct a cultural assessment for permits approved by the Michigan Department of Environment, Great Lakes and Energy last year.
"We did not limit the work of SEARCH in its assessment," he said. "Enbridge is committed to a process of identifying culturally and archeologically significant features in the Straits."
Group members behind the rock formations discovery say it warrants further evaluation by area tribes, state officials and scientists — and that Enbridge's Line 5 tunnel should not be allowed to proceed if it could potentially damage cultural sites on the lake bottom. The Michigan Department of Environment, Great Lakes and Energy is allowing public comments on Enbridge's wetlands and submerged lands permit requests for the tunnel project until Monday.
Said Duffy, "Side-scan sonar imagery was used to map the lake bed and we found no submerged cultural resources in the area that was assessed. We have not seen the report from the organization suggesting they have discovered significant features and we do not know if they assessed the same areas we did.
"We are open to sharing the information we have collected with tribal governments and learning more about the assessment done by this group. We have invited tribal governments to participate in identifying and protecting culturally and archaeologically significant features in the Straits. We would welcome the opportunity to meet and talk with this group."
Taking their own look
Terri Wilkerson learned about Enbridge's 67-year-old oil and gas pipelines on the Straits of Mackinac lake bottom around 2016. Learning more and more about the pipelines and potential Great Lakes risk, and seeing a scarcity of information about the the lines, she created a website, RetireLine5.org, with links to facts about the pipes.
Wilkerson, a 59-year-old, retired real estate broker who lives in Pinckney, Michigan, was listening in on June 25 as Ingham County Circuit Court Judge James Jamo granted state Attorney General Dana Nessel’s motion for a temporary restraining order requiring Enbridge to cease operations of Line 5. The move came after Enbridge reported significant damage to one of the twin pipeline's support anchors at the Straits bottom the week before. After inspections, the pipelines were allowed to resume full operation by September.
"In that hearing, Judge Jamo asked a number of times, 'Why do we have to trust Enbridge for all of this information? Why don't we have independently sourced information?' " Wilkerson said.
Wilkerson had become friends with Pierce after they'd crossed paths on their efforts in opposition to Line 5.
"I asked Andrea if we could get tribal support to go down there and have a look," Wilkerson said.
Pierce enlisted the help of Kelly Willis, 50, of Coleman, a citizen of the Saginaw Chippewa Indian Tribe.
"In our culture, women traditionally are water protectors, as all life comes from the water," Willis said, adding Wilkerson's and Pierce's appeal "hit that chord in my heart."
As Pierce and Willis worked their tribal contacts statewide to enlist support, Wilkerson worked on fundraising throughout the summer.
"COVID was the main thing on people's minds, and it took us the entire summer," Wilkerson said.
Eventually, they called upon Fred Harrington Jr., a former Navy submariner and retired IT professor who serves on the Little Traverse Bay Bands' tribal council, and Robin Lees, 65, of Cheboygan, Willis' cousin and a Little Traverse Bay Bands tribal elder, retired from 36 years as a teacher.
Harrington helped secure use of a shoreline space owned by the tribe in Mackinaw City as a staging area, and the group of women commissioned a boat equipped with a remote-operated underwater vehicle, or ROV, featuring side-scan sonar, a type of acoustic imaging allowing the ability to see with sound — bouncing ultrasonic waves in a way that maps large portions of a sea floor and detects objects upon it.
Before beginning their effort, Lees performed a water ceremony at the Straits, "honoring the water, and understanding the relationship that we, as humans, have with it," she said.
"The prayer I give is for gratitude but also prayers for healing and safety in the water."
The contracted boat went out on the Straits of Mackinac Aug. 30.
"It was when we were doing this side-scan sonar work when the contractor said, 'Huh — this might be a cultural site,'" Wilkerson recalled. "I had no idea there was even the possibility of a cultural site."
But further excursions were thwarted by uncooperative weather in the Straits, and Wilkerson ended work with the contractor.
"Fred said, 'Let's get our own ROV, and spend more time looking at this on our own,' " she recalled.
That price tag, however, was more than $25,000. That meant going back out to raise funds.
"I consulted with a few of the larger donors, to make sure they were OK with this," she said, declining to name them. "It's something that can be useful for us on water advocacy work in the future."
As they prepared to conduct their own ROV studies of the Straits, Harrington urged use of the Little Traverse Bay Bands' community canoe, called Jiimaan, which means "they are kissing" in the language of the Anishinaabek culture, which includes Odawa, Ojibwe and Potawatomi tribes.
The 32-foot canoe was built in 1999 by Harrington and others in part as a way to get in touch with the tribe's canoe-making past.
"He's like my best friend," said Harrington, who refers to the canoe as if it's a person.
"He's a little overbuilt. He's got giant ends, 32 feet long with 26-inch gunnels. You can be in big waves with that. I've been in 12-foot whitecaps and never took on a gallon of water. He also has a rounder bottom, so he won't flip."
Harrington said "having everything done off the Jiimaan, it just seemed right. It became a cultural activity in addition to a scientific expedition."
"I'm an engineer, but I live in two different worlds. When I get on the water, every time I dip my paddle into the water, it's like praying. I get a little closer to the Creator."
As late summer turned to fall, after days of waiting on wind and waves, Wilkerson and Harrington decided to make an attempt at getting ROV images on Sept. 23. Because of the foggy weather that they hoped would later burn off, they enlisted the help of a tribal fisherman, Scott Wyzlic, a citizen of the Grand River Bands of Ottawa Indians who lives near Mackinaw City, to tow the Jiimaan into place.
"This was the very first day we popped the ROV into the water," Wilkerson said.
The findings of stones in apparent formation on the bottom had Harrington, staring into the viewing screen for the ROV aboard the Jiimaan, exclaiming.
"It seems very clear to me that it's worth investigating," Wilkerson said. "These things look intentionally spaced to me as a lay person. They are evenly spaced, there are circles, there are patterns."
Wilkerson said she, Harrington, and the women she worked with are eager to make this information public before the public comment period ends on Enbridge's Line 5 tunnel project's wetlands and submerged lands permit requests on Monday.
"Because, obviously, it's critical to the conversation," she said.
Before the Great Lakes
The Great Lakes were formed after massive, miles-deep glaciers came down from the north more than 13,000 years ago, gouging deep gorges into the rock and earth and then filling them with water as the ice retreated. But that slow retreat took thousands of years, the melting waters of the glaciers creating vast, prehistoric lakes. And as the incredible weight of all that ice lifted, the pressed-down earth began to rebound, in different places at different times. This opened and closed channels and waterways, and caused the depths of those early lakes to fluctuate widely, from much deeper than today's Great Lakes to much shallower.
Between 11,000 and 9,000 years ago, a lake known as Glacial Lake Stanley existed in the area of modern Lake Huron with water levels that were more than 300 feet lower than the lake's current elevations, O'Shea said. The lake was named for geologist George Stanley, who determined its existence in the 1930s.
That meant that a great amount of land that's under water now was open, O'Shea said. "For a 2,000 to 3,000-year period, that was the state of play."
It was a time when ancient civilizations of "post-Ice Age hunters" roamed North America — and moved northward, following the retreating ice, O'Shea said.
"People think of the edge of a glacier as a formidable place," he said. "But it would have been a very rich place, attracting animals and hunters."
The Lake Stanley period of low water would have exposed the Alpena-Amberley ridge, a limestone and dolamite, nature-formed causeway averaging about 10 miles wide near Alpena. At the time, it would have provided an above-water land connection between modern northern Michigan and central Ontario.
O'Shea surmised that the ridge would have been particularly attractive to hunters, as it created an animal corridor relatively small in size. Caribou would have been abundant in the area at the time, O'Shea said.
"When you have caribou migrating across it, it made it very predictable. That was good for the hunters," he said.
O'Shea and researcher Guy Meadows at Michigan Technological University published a research paper in June 2009 entitled, "Evidence for early hunters beneath the Great Lakes," where they took an acoustic and video look of the now-submerged Alpena-Amberley ridge area in Lake Huron.
They found what they were looking for: rocks in linear patterns that O'Shea believes were used to drive and channel caribou, and evidence of hunting blinds.
O'Shea said it makes sense that similar finds would be in the Straits of Mackinac, which at the time would have been a large, river-like channel between two large lakes.
"You can imagine it as a very rich, very strategic kind of location if you're a hunter," he said.
It was at the Conference on Historical and Underwater Archaeology in Boston in January when O'Shea said a colleague "took me aside and told me his concerns about what was happening with the (Enbridge Line 5 tunnel project) environmental assessment."
O'Shea would not name the archaeologist, who he said fears employment-related repercussions.
"There's almost a conflict of interest in there if you're a consultant working for one of these firms because your employer wants there to be no complications," he said.
O'Shea said the consultant showed him, but didn't allow him to copy, a concluding finding "that there was a moderate to high probability of there being prehistoric relics in the (Line 5 tunnel) impact area."
O'Shea wrote his February letter to MacFarlane-Faes "to try to, if necessary, tip off the State Historic Preservation Office that they should look at it," he said.
He received no response to his letter. "I tried doing some informal contacts, and couldn't get any response from anybody," he said. "I then sent it to (State Attorney General Dana Nessel's) Office because I knew they had people there who were interested in Line 5."
Underwater archeological finds are especially enlightening for researchers, O'Shea said.
"These stone structures, they're rocks. They don't survive on land because of development, farmers clearing fields, other things. But under water, they are so perfectly preserved, Pompeii-like, on the lake bottom. But they are also easy to destroy.
"My concern is that they simply don't destroy something that might be there."
Tribes will study
Michigan Department of Environment, Great Lakes and Energy spokesman Hugh McDiarmid Jr. said the cultural assessment portion of Enbridge's wetlands and submerged lands permits for the Line 5 tunnel project were received earlier this year and forwarded to the State Historic Preservation Office. Messages left with that office were not returned.
"I understand that SHPO (the State Historic Preservation Office) has seen Professor O'Shea's letter, and are also aware of tribal concerns in the area," McDiarmid said.
Because all but the entrance and egress points of the proposed pipeline tunnel will be encased in bedrock, "our feeling is that this route through bedrock greatly reduces the likelihood that it would be routed through preserved historic artifacts," he said.
As the Straits-area waters are also regulated by the federal government, McDiarmid added that a federal review of the project's cultural assessment will also take place.
Said O'Shea, "If they don't disturb it, that's great. But my understanding is that some of the spoils from the tunnel digging are going to go back onto the lake bottom."
Harrington said his and other tribes will be eager to learn more about what may be on the Straits bottom.
"We're talking about it now," he said. "We'll adopt it as part of who we are because it's on our lands. We're really into preserving what we find. Our education department will use those things for cultural training, making sure everyone has an opportunity to learn about them."
Wilkerson has a clear idea of what she thinks needs to happen next.
"Enbridge should be shut out completely on this," she said. "The tribes first, and the state, should take the lead on investigating this. And Enbridge should be blocked now from disturbing anything in that area.
"This is a big deal, it seems to me."
Follow Detroit Free Press reporter Keith Matheny on Twitter @keithmatheny.
This article originally appeared on Detroit Free Press: Under Great Lakes, group may have found evidence of Ice Age culture