Portage Lake Harbor, Michigan is located on the west shore of Lake Michigan, about 186 miles northeasterly from Chicago, Illinois, and about 37 miles northerly from Ludington, Michigan. The project was authorized by the Rivers and Harbors Act of 3 March 1879. The project provides for a harbor of refuge with an entrance channel from Lake Michigan to Portage Lake 300 feet wide and 18 feet deep protected by stone filled timber crib piers and wood pile revetments. The piers and revetments have been provided with concrete superstructures. The harbor services primarily recreational navigation interests.