About Diamond Lake

“It’s a beautiful lake with clean water!”

- S. N.

Diamond Lake is located in southwest lower Michigan, in nearly the center of Cass County. It is situated southeast of the village, and county seat, Cassopolis. Four different townships intersect in its waters; Calvin, Jefferson, LaGrange, and Penn. The lake is 1,078 acres in size, 60% of the lake is less than 10 feet deep, and is 64 feet at its deepest. Most of its shoreline is lined with over 900 homes and cottages, including an occupied island of about 43 acres in the center of the lake, accessible to island residents by the privately owned barge/ferry during the summer months. There is one marina on its shores, and one public boat launch.

View & Download “Diamond Lake: A Resource and Guidebook for Residents”

View Lake & watershed facts, info about water health, how you can help protect the Lake, and more.

Diamond Lake History

Historical information was compiled by Jean Schultz, using local resources including the book A Diamond Sparkles by Lois Webster Welch