What's at the Bottom of Minnesota's Lakes? These Marine Archaeologists Are Finding Out

Husband and wife team of marine archaeologists have made it their mission to study what’s at the bottom of local lakes.

Despite Minnesota’s early reputation as a pioneer in understanding its rich maritime history, there are only two licensed marine archaeologists in the state today. They’ve made it their mission to study what’s at the bottom of local lakes—including Lake Minnetonka—in order to better understand our past.

It’s no secret that our lake is a big reason for our area’s popularity. Just like they’ve done for generations, people flock to Lake Minnetonka for the fishing and the boating and the sunshine, the beautiful lakefront homes, the restaurants and businesses that dot its shores.

Christopher Olson and Ann Merriman of St. Paul come to Lake Minnetonka for a different reason: its murky bottom.

As the only two licensed nautical, underwater, and maritime archaeologists in Minnesota and founders of the nonprofit Maritime Heritage Minnesota (MHM), the husband-and-wife team meticulously study the lake bottom in search of wrecks and artifacts that might tell us more about our past. They keep a boat on Gideon Bay—at the home of MHM board member Mike Kramer—and have done several grant-funded surveys of the lake, cruising back and forth in 200-foot increments. They’ve mapped out some 775 anomalies of interest to date.

This summer, they’re diving on wreck Nos. 77 and 83 in Lake Minnetonka, documenting what they find in online reports. So far, they’ve found a cabin crew boat, still on its trailer, that floated a mile from the launch before sinking. They’ve found a boat that was likely pulling a skier at night, because its lights were up and its rope was out.

They found an Alumacraft Center Console Model R whose incredible story they confirmed in an old newspaper. Fourteen-year-old Tony McKeown had been on-board when it sank, and drowned, but was resuscitated. They found the man—now in his 80s—and told him about their find. “That’s what we love: not just finding wrecks, but finding out their stories,” says Olson. “We’re preserving windows to our past.” The pair are quick to explain that their work has nothing to do with finding treasure or raising artifacts, but of documenting what’s at the bottom of local lakes and waterways in order to preserve and understand history.

“People have been sinking old boats intentionally for eons,” adds Merriman. “I see the lake as a huge piece of maritime infrastructure.
It represents subsistence. It’s where native people planted rice and buried their dead. It’s a transportation route. Minnesota is perfect for wrecks—with fresh, cold water—so our wrecks are pristine. You take off the zebra mussels, and they’re gorgeous. We are a maritime culture. It’s so important to preserve and understand it.”

Minnesota’s Maritime Heritage

1876 The date an 85-foot barge—owned by James J. Hill—was built. It sank in 1879 in a storm on Wayzata Bay, and has been known to divers for years. When MHM dove on it in 2012, they discovered her pristine condition and successfully nominated the site to the National Register
of Historic Places.

1934 “The Lake Minnetonka North Arm Dugout Canoe” was found by Helmer and Arthur Gunnarson, who hit an obstruction when extending their dock. They raised what they thought was a log, and realized it was a canoe, excellently preserved by the mud and silt.

1936 Phillips screwdrivers were invented, making a handy benchmark for dating wrecks. “From before that, we’ve found mostly handmade, cheap boats for fishing—all with flathead screws,” Olson says.

1989 The year a fiberglass motorboat sank with a fully-intact duffle bag in it—complete with a broken Rolex watch, New Balance tennis shoes, a wallet, a 1987 Twins World Series t-shirt, and Vikings Zubaz pants. MHM received a license from the office of the state archaeologist to raise the artifact and returned the bag to its owner.

2005 Maritime Heritage Minnesota becomes the only underwater archaeology firm in the state, and the only non-profit of its kind nationally.

2011 The year MHM did its first survey of Lake Minnetonka

2014 MHM receives a Minnesota Historical and Cultural Heritage Grant to use radiocarbon dating to determine the age of dugout canoes. They determine that the dugout canoe found in Lake Minnetonka in 1934 is roughly 1,000 years old. 

287 anomalies and 79 confirmed wrecks investigated (and counting) Any abnormal signal becomes a target, and then Olson and Merriman work their way through them.

76 wrecks documented. Fun fact: On the ocean, large boats are called ships. Once they enter the Saint Lawrence Seaway or any inland waters, they’re referred to as boats.

20 ft Height of a possible ship that was detected standing perfectly on-end in the silt under 72 feet of water. “Usually the engine is at the stern, but not in this case,” says Olson.

6 cars, 4 snowmobiles, and a pick-up truck If this isn’t motivation to stop playing chicken with thin ice, we don’t know what is!

What’s That?
Though Minnesota’s cold lakes make for relatively good visibility, Olson and Merriman train for zero-visibility dives—and are used to navigating by feel. When they get to something of interest, and can’t see well enough, they use a “Brody Bag” like a magnifying glass. It’s just a baggie of clean water, but held up against a hard-to-identify feature, it can bring the spot into focus.

White Stripe = Stay Away
“People don’t read their boating manuals!” Merriman says, noting that state law requires they dive with a red and white “Diver Down” flag visible above-water—with no more than four divers per flag. But despite their best efforts at safety, they’ve had some close calls. “We’ve had fishermen troll right up to us to ask what we’re doing—they could have taken someone’s head off with their propeller.” For that reason—and better visibility—they do most of their dives in late fall or early spring when the water is colder, clearer and less busy.

Maritime Heritage Minnesota
Facebook: Maritime Heritage Minnesota
Twitter: @MaritimeMinn