WAYZATA - The wrecks at the bottom of Lake Minnetonka tell a story about the history of the lake, and the underwater archaeology duo Ann Merriman and Christopher Olson of Maritime Heritage Minnesota work to preserve it and share what they find with the public.
Maritime Heritage Minnesota recently released its Lake Minnetonka Nautical Archaeology 8 Project Report, which details the 10 new watercraft discovered on the bottom of Lake Minnetonka.
Merriman, Olson and volunteers conducted fieldwork from June-September 2018. They used improved sonar equipment and scuba diving to investigate 27 unknown anomalies and one known shipwreck at the bottom of Lake Minnetonka. An anomaly is sonar data that may be an object, such as watercraft (a wreck), a vehicle, a tree or a rock.
The team discovered 10 new wrecks, six submerged maritime sites, three snowmobiles, two trees and two big rocks, as well as a bunch of other objects at the bottom of the lake. Then the group did research to place the wrecks and archaeological sites into historical context so Minnesotans can learn from what sits at the bottom of their lakes.
One of the most interesting wrecks Merriman and Olson said they've found during their time as the state's only two underwater archaeologists was identified over the summer in Lake Minnetonka.
Maritime Heritage Minnesota identified a 21.5-foot-long wooden gasoline launch named Theta after rescanning an anomaly in June 2018. The launch was likely constructed in 1900 and sank around 1920, the group notes.
Benches on the launch indicate Theta was used for passenger transportation around Lake Minnetonka, noting it is small enough to access both Upper and Lower lake easily, as well as shallower bays and shorelines.
"The survival of the gasoline launch Theta wreck on the bottom of Lake Minnetonka greatly enhances Minnesota's maritime history - currently she is a one-of-a-kind nautical archaeological site in our state," the Lake Minnetonka Nautical Archaeology 8 Project Report says.
The Theta nameplate is attached to the launch's port and starboard bows, which should help the team research the complete history of the watercraft. However, to date "no mention of Theta has been located in the maritime historical record," the report adds.
Besides the Theta, Maritime Heritage Minnesota identified nine other wrecks in summer 2018. They are:
"As more Minnesota wrecks are documented, the changes in watercraft design and construction will more completely fill-out the maritime historical record. Many of the smaller craft on the bottom of Lake Minnetonka represent nearly 140 years of our relationship with historical personal watercraft," the report says.
Maritime Heritage Minnesota also identified a bunch of other objects in the lake, such as a tablecloth, a pontoon, a boat canopy, a dock site, part of a small shed, a metal barrel, a cable and a dock slide and ladder.
There are now a total of 76 identified wrecks at the bottom of Lake Minnetonka (or were at the bottom, a Woodland Culture dugout canoe was removed from the lake in 1934), as well as seven cars, one truck and four snowmobiles.
In its report, Maritime Heritage Minnesota said it "is confident there are many, many more snowmobiles still sitting on the lake bottom."
A "major outcome" of the project was attaining eight Minnesota Archaeological Site numbers for eight of the wrecks investigated over the summer, Merriman and Olson told Lakeshore Weekly News.
The wrecks that received site numbers are: Theta, Half-Decked Barge, Fisherman's Friend Wreck 4, Wooden Motor Boat Wreck 3 and 4, Aluminum Motor Boat, Steel Motor Boat and Shell Lake Portager Wreck, which was identified in 2011 as Small Aluminum Wreck but Maritime Heritage Minnesota took another look at it in 2018 and re-identified it.
The Minnesota State Archaeologist gives site numbers to locations that contain "evidence of past human use that holds potential for archaeological understanding of the past," meaning multiple archaeologists must be interested in this site, according to the state archaeologist's website. To be worthy of a site number, the archaeological site must be at least 50 years old, be confirmed by field survey, and have a state site form submitted.
To help Maritime Heritage Minnesota identify some of these archaeological sites, the group used new sonar equipment. This equipment offered improved clarity to allow for clearer images and sharper features, which allows the group to identify some anomalies without SCUBA diving to the site. This helps the not-for-profit organization save money, which is important because much of the work they do is funded through the Minnesota Historical and Cultural Heritage Grants Program.
Maritime Heritage Minnesota was founded in 2005 with the mission of identifying, documenting and preserving Minnesota's submerged cultural resources, the group's website says. The wrecks and archaeological sites it finds are protected under state and federal laws, and Merriman and Olson stress the importance of preserving the state's maritime history for future generations, which is why they don't remove artifacts unless it is absolutely necessary.
For more information on Maritime Heritage Minnesota, as well additional information and videos of what they've discovered in Lake Minnetonka, visit: http://www.maritimeheritagemn.org/index.html