The Convention prohibits the dumping of any kind of trash, garbage, sewage or other wastes in the inland waters of the United States, or within three nautical miles of shore. This prohibition includes laundry discharge, galley (kitchen) discharge and dumping of wasted food.
In the area that lies more than three nautical miles, but less than 12 nautical miles, from shore--the territorial waters of the United States--the Convention prohibits the dumping of cargo bracing (called "dunnage"), packing materials that float or any waste not ground to less than 1 square inch. Although a food waste, cooking oil is considered "oil" and its dumping is prohibited under a different annex to the Convention. The discharge of sewage and gray water (the "used water" from laundry and galley) is also permitted in this area.
Garbage may only be disposed of ashore, at facilities designated by the shipping company or the Coast Guard.
The dumping of plastic in any form is forbidden in both areas.
At distances greater than 12 miles from shore, the restrictions on dumping relax somewhat. The dumping of dunnage, packing materials that float and plastic are specifically forbidden in the zone beginning 12 nautical miles from shore and extending out to 25 nautical miles from shore. All other garbage, including sewage, gray water, food waste (except cooking oil or garbage containing any amount of plastic) may be "tossed over the rail" in this zone.
At more than 25 nautical miles from shore, the only dumping restriction is on plastic, without regard to the size or nature of the plastic. In its Review of Annex V of the Convention, the International Maritime Organization (IMO) says, "The greatest danger comes from plastic, which can float for years. Fish and marine mammals can in some cases mistake plastics for food and they can also become trapped in plastic ropes, nets, bags and other items--even such innocuous items as the plastic rings used to hold cans of beer and drinks together."
Annex V of the Convention requires that cruise ships "of 400 gross tonnage and above and every ship certified to carry 15 persons or more" are required to have a Garbage Management Plan outlining the procedures for "collecting , storing, processing and disposing of garbage, including the use of equipment on board." The plan must designate who is responsible for its implementation and be written "in the working language of the crew." Part of the Garbage Management Plan involves the keeping of a "garbage log," describing where, when and by whom garbage was disposed.
