46 CFR § 45.185
Tow limitations
April 15, 2021
(a) Barges must not be manned.
(b) No more than a total of three barges per tow may operate on the Milwaukee, St. Joseph, and Muskegon routes. A mixed tow of load-lined and exempted barges is still limited to three barges on those routes.
(c) Tows must not be more than 5 nautical miles from shore.
[USCG-1998-4623, 67 FR 19690, Apr. 23, 2002, as amended at 75 FR 70604, Nov. 18, 2010]