Brownie Lake

Gazing across Brownie Lake, one might wonder about its unique stillness. Brownie Lake is a meromictic lake. This means its waters rarely mix. This unique characteristic sets Brownie Lake apart in the Minneapolis Chain of Lakes. It’s the northernmost lake in this chain, nestled within Brownie Lake Park and overseen by the Minneapolis Park and Recreation Board. Brownie Lake is a small body of water, covering just 18 acres. Its average depth is about 20 feet, with the deepest point reaching nearly 50 feet. The name “Brownie” comes from Agnes McNair, the daughter of William McNair, the original landowner. Her nickname was “Brownie,” and the name stuck. It was once called “Hillside Harbor,” but the name Brownie Lake prevailed. The railroad significantly impacted the lake’s size in 1883. The construction of the tracks alongside it reduced the lake’s surface area by a third. Further changes came in 1917 when a channel was created to connect Brownie Lake to Cedar Lake. This caused the water level to drop significantly and further shrunk the lake’s area. The peculiar stillness of Brownie Lake stems from its meromictic nature. The distinct layers of water, separated by a chemocline, don’t intermix. The bottom layer lacks oxygen and holds high concentrations of dissolved iron. Historically, these levels were between 1-2 mmol/L, and they still remain above 1 mmol/L today. From 1950 to the 1990s, an industrial cooling outlet discharged into Brownie Lake. This discharge from the Prudential Office Building added even more iron to the lake. Today, Brownie Lake offers a peaceful escape. A packed dirt path encircles the lake, perfect for a leisurely stroll. The Cedar Lake Trail, a paved multi-use path, runs nearby for those seeking a longer journey. Although motor boats are prohibited, canoes and kayaks glide serenely across its surface. In winter, the Chain of Lakes Ski Trail extends across Brownie Lake, offering cross-country skiing opportunities. Brownie Lake is more than just a still body of water. It is a place with a rich history. It has unique characteristics. It is a reminder of how human intervention and natural processes shape the landscape.