33 C.F.R. § 3.45-15
Sector Lake Michigan's office is located in Milwaukee, WI. The boundaries of Sector Lake Michigan's Marine Inspection Zone and Captain of the Port Zone include all navigable waters of the United States and contiguous land areas within the boundaries of an area starting from a point at latitude 44°43'00" N, longitude 84°30'00" W, proceeding due west to longitude 85°40'00" W; thence northwest to the eastern shore of Lake Michigan at latitude 45°01'00" N; thence northwest to latitude 45°22'30" N, longitude 86°19'00" W; thence northeast to latitude 45°41'00" N, longitude 86°06'00" W; thence northwest to latitude 46°20'00" N, longitude 87°22'00" W; thence west to latitude 46°20'00" N, longitude 90°00'00" W; thence south to latitude 41°00'00" N; thence east to the Ohio-Indiana border at latitude 41°00'00" N, longitude 84°48'12" W; thence north along the Ohio-Indiana border to the intersection of the Ohio-Indiana-Michigan border at latitude 41°41'59" N, longitude 84°48'22" W; thence east along the Ohio-Michigan border to latitude 41°42'13" N, longitude 84°30'00" W; thence north to the start point.
33 C.F.R. §3.45-15