What is a garbage management plan and what does MARPOL require?

A garbage management plan is the working document, required by MARPOL Annex V, that turns the international rules on garbage into specific procedures for one particular ship. Annex V starts from a simple principle: discharging garbage into the sea is prohibited except in a few tightly defined cases, and plastics may never be discharged anywhere. The plan says who does what: how garbage is collected around the accommodation, galley, engine room and deck, how it is separated at source into categories such as plastics, food waste, paper and rags, oily waste, operational waste and e-waste, where the labelled bins and storage areas are, and how each stream is either processed on board (compacted, comminuted or incinerated) or retained for landing to port reception facilities. It names the person responsible for carrying the plan out, usually a designated officer, and it must be written in the working language of the crew.

The applicability thresholds are worth knowing for inspections: every ship of 100 GT and above, and every ship certified to carry fifteen or more persons, must have a garbage management plan; ships of 400 GT and above, and those carrying fifteen or more persons on international voyages, must also keep a Garbage Record Book; and all ships of twelve metres or more must display placards stating the discharge rules. The record book logs every discharge to sea, every incineration and every landing ashore, with date, time, position, category and quantity, and receipts from reception facilities should be kept with it.

What may still legally go overboard is narrow: food waste, generally not less than 12 nautical miles from the nearest land while en route, or not less than 3 miles when comminuted to pass a 25 mm screen; certain cargo residues classed as not harmful to the marine environment beyond 12 miles; and cleaning agents that are not harmful. In special areas the rules tighten further, with little beyond comminuted food waste even considered.

Port State Control checks the plan, the record book entries against soundings and receipts, and whether the crew actually know the procedures. Discrepancies are a common source of deficiencies and, in cases of deliberate dumping, prosecutions and heavy fines. Run garbage like any other controlled operation: separate at source, record honestly, land ashore whenever in doubt, and never let anyone treat the ship's rail as a disposal route.