Ancient Waterfall Discovered Off Mackinac Island's Shoreline
An ancient 100-foot waterfall off the shore of Mackinac Island was discovered underwater last week by the crew aboard the training and research vessel The Pride of Michigan. They came across the 10,000-year-old waterfall while taking soundings in the area.
The waterfall is part of an ancient and now-submerged river, called the Mackinac Channel, that flowed through the Straits before the existence of Lake Michigan and Lake Huron.
"It is not as large as Niagara," said Captain Luke Clyburn, "but it is a very, very significant waterfall."
Now lying 110 feet beneath the surface of Lake Huron, just off the east shore of Mackinac Island, the site shows that water flowed from west to east along the channel before plunging nearly 100 feet from a limestone cliff. Soundings recorded Thursday, August 16, revealed the cliff and sharp drop in the riverbed.
From research in the area two years ago, Captain Clyburn speculated that a rapids or a waterfall might exist. While testing new sounding equipment Thursday, his suspicions of a waterfall were confirmed based on readings from the site.
"We'll be back up doing more work in this area," he said, "now that we've pinpointed the waterfall."
In conjunction with training for U.S. Naval Sea Cadets, the ship conducts underwater research and is on a mission to learn about and find areas inhabited by cultures 10,000 years ago.
The discovery of the waterfall on the former 80-mile-long river, said Captain Clyburn, increases the probability that people lived nearby, and it increases the chances of finding evidence of them on future dives.
The existence of the ancient river channel was found on soundings taken in the 1930s and later confirmed when spruce stumps discovered about 120 feet beneath the surface of the Straits were carbon-dated to 10,000 years ago.
Captain Clyburn, who has been doing research on the Great Lakes for 30 years, has a similar piece of wood hanging on the wall of the ship's bridge. That piece was discovered in lower Lake Huron, and has been carbon dated to approximately 7,000 years ago.
The primary mission of the ship is to train sea cadets. Some operation funds come from Michigan Coastal Management, administered through Michigan's Department of Environmental Quality. On this trip, as part of a larger documentary project, entitled "Ancient Shorelines in Lake Huron," the crew is filming and documenting underwater observations.
Two years ago, while working in the area, Captain Clyburn said they discovered that Traverse Bay was once independent from Lake Michigan and they discovered the submerged river that had connected the two. Also discovered on the north side of Traverse Bay, near Norwood, was a chert mine that was operated 10,000 years ago. The mine yielded a form of flint, and tools were found related to its operation.
"There was a lot [more] going on in that period of time than we understand," he said.
They are now expanding their search to the Straits area.
"We're looking for culture that may have existed in this area 10,000 years ago," he said. "There is no question they were here. We know very little about them. Our history doesn't go back that far. We're working with scientists to try to develop that history after the glacier."
The water trail flowed from the Lake Michigan area, through the Straits, and into what now is known as Lake Huron. The channel first passed north of Mackinac Island, and then it dipped south along the Island's east coast.
Strong winds and high seas Thursday, August 16, called a halt to the work. The ship and crew spent the night moored at the Arnold Transit dock on Mackinac Island before heading out Friday morning to make additional soundings that would confirm the height of the falls, which Captain Clyburn estimated to be between 80 and 100 feet.
Niagara Falls, in comparison, has a drop of 70 feet to rocks at the base. Without them, water would descend 176 feet. The upper waterfall at Tahquamenon Falls has a 50-foot drop.
Niagara Falls, on the Niagara River, said Captain Clyburn, was not the largest waterfall in the Great Lakes basin. When the Mackinac Channel existed, he said, all the water was flowing though Georgian Bay. Over the last 20 years, Canadian researchers have been researching a waterfall they have found between Flower Pot Island and the Village of Tobermory in Ontario.
"That's where all the water was draining," he said. "There was not a Detroit River. There was not a Lake St. Clair."
The Pride of Michigan is one of three U.S. Naval Sea Cadet Corps boats on the Great Lakes, and the only one that is used for scientific research. The ship's homeport is on the Clinton River in Mount Clemens. From there it sailed to the St. Clair River and then into Lake Huron to begin the research and filming project.
On board the 80-foot, 80-ton former U.S. Naval Yard patrol boat is a crew of 10 adults and 16 U.S. Naval Sea Corps cadets ranging from 13 to 18 years old. The team has been conducting a 10-day archaeology and geology research mission. Their work was performed using soundings and scuba diving. All crew are certified in scuba diving.
The project ended Sunday, August 19.
"It is a great program," said Cadet Joshua White of Ibadel, Oklahoma, who wants to become involved in the Navy Sea, Air and Land (Seal) forces. The entire program has been a great experience, he said, and diving in Lake Huron "is very cold, but very fun."
Sponsored by Navy League and the U.S. Navy, the U.S. Naval Sea Cadet Corps serves as an introduction to naval life, although students are not required to enter the military. The program also teaches cadets teamwork, leadership, discipline, and responsibility.
"What we do is very, very unique to any other program in the country," said Captain Clyburn.
Cadets onboard the Pride of Michigan spent two weeks in boot camp at the Naval Station Great Lakes in Great Lakes, Illinois.
Two years ago, Jean-Michel Cousteau, the son of Jacques Cousteau, and his crew spent four days aboard the Pride of Michigan to film "America's Underwater Treasures." The series of shows about shipwrecks aired on PBS stations last fall. The Lake Huron filming took place exploring the ships Audubon and Defiance, which collided in fog and sank in 1854.
Cadet Nathan Dembeck worked with the Cousteau film crew and has been offered a job with the crew as an underwater photographer. He is planning on joining the Cousteau team soon.
Authorized by the Secretary of the Navy, cadets wear Navy uniforms that are marked with sea cadet insignia.
Three cadets are stationed on the ship's bridge at all times, while two work in the engine room and one is on roving watch. Soundings are performed while the ship is underway. All of the cadets bunk in one large room on the main deck and are scheduled on shifts around the clock.
After leaving Mackinac Island Friday, the crew planned practice dives while making their way back to the Clinton River.
"Where else can a 13-yearold learn how to operate two diesel engines?" asks Matt Konen of Shelby Township, who plans to fly helicopters for the Coast Guard. "I love this program."