D.C. Mun. Regs. tit. 6, r. 6-A101
The harbor jurisdiction shall be under the command of an official of the Metropolitan Police Force.
The harbor commander shall be held responsible for enforcing the laws and regulations relating to the harbors and rivers within the District of Columbia, and in the conduct of that office, shall be subject to the rules for the guidance of commanders insofar as those rules are applicable.
The harbor commander, while on duty, shall devote his or her entire time and attention to the preservation of life and property, the maintenance of peace and order, and the proper regulation, according to law, of any and all vessels, of whatsoever character and kind, on the Potomac River and its navigable tributaries within the jurisdiction of the District of Columbia.
The harbor commander shall require observance of the laws and regulations applying to the wharves and places adjacent thereto and shall see that they are kept free from nuisances, improper encroachments or obstructions, and anything dangerous to life and limb.
D.C. Mun. Regs. tit. 6, r. 6-A101