Big Bay Harbor, Michigan is located on the south shore of Lake Superior, 33 miles northwesterly from Marquette, Michigan, and 38 miles easterly from the Portage entry to the Keweenaw Waterway. The project was authorized by the 1945 River and Harbor Act. This project provides for two converging rubblemound breakwaters extending from shore, the east pier 471 feet long and the west pier 787 feet long; an entrance channel between piers which is 80 feet long with a 12 feet and flared at the outer end; and for a rectangular harbor basin 100 feet wide, 430 feet long and 10 feet deep. Local interests have expended the harbor basin widening the basin about 50 feet on each side to a depth of 6 feet on the north and 8 feet on the south, and by lengthening it about 100 feet with a depth of 8 feet. The harbor services primarily recreational navigation interests.