Gooseberry State Park, Minnesota

November 23, 2009

Gooseberry11

Photographer: Dale L. Hugo
Summary Author: Dale L. Hugo; Stu Witmer

The photo above is a view looking up at the Fifth Falls on the Gooseberry River in northeastern Minnesota's Gooseberry Falls State Park. The bridge gently arching over the approximately 15 ft high (5 m) falls is built with weathering steel which is made to rust to protect itself from further oxidation, unlike other steels that rust worse as time goes along. Notice the tannin in the water that gives it the color of tea or root beer. Tannin comes from the sphagnum moss in the swamps at the headwaters of this river. During the spring snow melt, huge amounts of water and sediment are pushed down Gooseberry River. The bedrock beneath the river is predominately basalt from the Precambrian Gooseberry Lava Flows laid down about a billion years ago. More recently, glaciers covered the area cracking the rock and gouging out a basin for Lake Superior which was subsequently filled with meltwater when the glaciers retreated 10,000 years ago. In the thousands of years since then sediment-laden water swirled over the falls eroding holes in the vertical walls of the small canyon confining the river. High volume and flooding can occur in other seasons as well, but peak daily flows generally occur in springtime. Situated on Lake Superior's North Shore, Gooseberry State Park is the second most visited state park in Minnesota. It offers more than 20 miles (32 km) of hiking trails, including a portion of the 244 mile (393 km) Superior Hiking Trail, as well as trails for biking, cross country skiing, snowmobiling and snowshoeing. Photo taken on August 12, 2009.

Fifth Falls coordinates: 47.147N 91.475W