Sunken History—A Diver's Journal
The Drowned Forest of Sanilac
by Captain Deb Biniecki

Several years ago, while participating in search and recovery training for the Sanilac County Sheriff's Dive Unit, Duane and Patsy VanConnant stumbled upon something odd. They surfaced to report observing several large logs in about 40 feet of water. Other members of the unit, including Tim Juhl, Jim and Pat Stayer, Tom Wilson, Tom Orton, Gene Taylor, my husband Garry and myself, joined in the exploration of the site. Upon further inspection, it appeared that these logs were not just dumped there. They were once growing there! Tim took a sample for carbon dating, which revealed that the stumps had been there for at least 7,000 years.

Sites such as this are found in several areas around the Great Lakes. Over 2 million years ago during the Pleistocene Epoch, know as the 'Ice Age', much of North America was blanketed in mile-thick ice, including Lake Huron. During this time, there were many periods of expanding and retreating glaciation, creating lake levels both much lower and higher than at the present time.

About 10,000 years ago as the last glacier retreated, water levels were at the lowest, possibly 300 feet lower than present. During this period called the Stanley Low, forest growth covered part of what is now Lake Huron. When the glacier released, the land shifted, cutting off outlets to the east and filling the basin. The St. Clair River did not exist at the time as an outlet for the rising water. As the glacier melted during the Napissing Transgression, the water levels rose and flooded forested areas, creating the drowned forests.

From 1999 to 2001 the Sanilac drowned forest site was studied by a team of researchers led by Dr. R. D. Hunter of Oakland University in a joint project involving Inter-Seas Exploration and the Great Lakes Division of the U.S. Naval Sea Cadet Corps. SCUBA divers documented the site, which is scattered over about a seven acre area. The divers marked off a grid pattern covering the area and completed an inventory of each cell.

The researchers documented 500 pieces including logs, branches, roots and stumps. They located 10 stumps still rooted in growth position, some remains as large as five feet in diameter. Samples were taken for carbon dating and a few stumps were cut for tree ring dating. Analysis indicated the samples dated from 7409-7936 years before present. Most were determined to be some type of spruce, cedar, pine or hemlock, with only a few being hardwoods. Tree ring dating showed one spruce stump to be a 157 years old when it died. Amazingly, these logs are still preserved and relatively intact. Dr. Hunter suggests that it is likely that the trees were first buried by sand dunes which later flooded. Once the dunes were submerged the sand was redistributed, exposing the trees.

The drowned forest is located a few miles east of the Lexington Harbor in about 40 feet of water. If you were to visit the site today you would find mostly branches and logs as the trees sheered off over the years from exposure. The structures range from a few inches to about a foot and a half high. There are several of these sites in Lakes Huron and Michigan that have been documented. Researchers believe that there are likely other sites such as this in Lake Huron that are yet to be discovered.

If you would like to contact Capt. Deb with any ideas, feedback, or information regarding shipwreck stories, please contact her through Huron Explorations at 810-648-4638 or e-mail at captdeb@avci.net. SCUBA diving charters can also be arranged through the above contact information.