It is unlawful for the owner, agent, or lessee in charge of any dock or waterfront structure to allow the whole or any part thereof to fall into or remain adrift in the waters of the City or to float away from the dock.  All fender piling or other portions thereof that shall break loose shall be removed at once by the owner, agent, or lessee of any dock; and upon failure to do so, the same shall be removed by the Harbor Master and the expense thereof shall be paid by and recoverable from the owner, agent, or lessee of the property by the City.  In the event that any part of a dock or waterfront structure caves in, collapses, or is damaged in any way in excess of $1,000, the owner, agent, or lessee in charge shall notify the Harbor Master within 72 hours.