“Obstruction” means any vessel or any matter which may in any way blockade, interfere with or endanger any vessel or impede navigation, or which cannot comply with the “Pilot Rules for Certain Inland Waters of the Atlantic and Pacific Coasts and of the Coast of the Gulf of Mexico.” (Ord. 1937 § 15, 1997: Ord. 377 § 4 (part), 1965).