Approximately 1600.
I own a boat on Lake Michigan, and am certainly a "numbers guy." Lake Michigan and lakes of this size are so huge that they are measured not in acres, but typically in square miles. The Lake is 22,400 square miles which translates to 14,336,000 acreas of surface area. 5th largest lake in the world.
The lake is about 2,560 acres.
Lake Mead's area is 158,720 acres.
Lake Lanier is 38,000 acres
The lake covers 180 acres.
255 acres as of 2007
58,500 acres.
It is 917 acres.
Lake Champlain covers an area of 313,600 acres.
The lake has a surface area of 87,040 acres.
The lake has 71,100 acres of surface area.