The purpose of the Big Mantrap Lake Association as stated in the Articles of Incorporation is, "Maintaining and improving the natural resources of Big Mantrap Lake, Hubbard County, Minnesota, a public lake."
Mantrap Lake is located two miles east of Emmaville in central Hubbard County, Minnesota. It has a surface area of 1556 acres, average water clarity of 13 feet, and a maximum depth of 68 feet. About 752 acres (48 percent) of the lake is 15 feet deep or less. Mantrap is a diverse lake with numerous bays, islands, and channels and over 22 miles of shoreline. Mantrap is well known for its muskie fishery but also supports fishing for northern pike, bass, and black crappie.