Carriage, Handling and Storage of Dangerous Goods along

VESSELS 81
Special attention is needed for oily bilge water from vessels and cargo residues from tankers which
on the Mekong River mostly carry petroleum products. Oil is the most studied form of pollution from
shipping and is estimated to contribute about 45 percent of the total petroleum input into the marine
environment. (EMARC Project, Research and Development VII-E, WA-95-SC-097 Page 29).
On a ship, oil often leaks from engine and machinery spaces or from engine maintenance activities
and mixes with water in the bilge, the lowest part of the hull of the ship. Oil, gasoline, and byproducts
from the biological breakdown of petroleum products can harm fish and wildlife and pose threats to
human health if ingested. Even in minute concentrations, oil can kill fish or have various sub-lethal
chronic effects.
Bilge water also may contain solid wastes
and pollutants containing high amounts
of oxygen-demanding material, oil and
other chemicals. For instance, a typical
large cruise ship will generate an average
of eight tonnes of oily bilge water for each
24 hours of operation. Different sources
estimate that about two percent of daily
heavy fuel oil (HFO) consumption and
about 0.5 percent of the daily marine
diesel oil (MDO) consumption remains
as sludge. 16 To maintain ship stability
and eliminate potentially hazardous
conditions from oil vapors in these areas, Figure 17: Waste Reception Facility on Danube River
the bilge spaces need to be flushed and
periodically pumped dry. Bilge water
should be pumped over to reception facilities or bilge barges, designed for collecting bilge water. Along
the Mekong River, however, untreated oily bilge water is mostly discharged directly into the river,
where it can damage aquatic life.
Bilge water pumped overboard is a very important and serious form of continual pollution taking into
consideration the number of barges sailing and therefore needs special attention. Inland Navigation
Europe reported in June 2011 that a mobile bilge-water collection vessel had started on the Danube
River in Austria and Hungary. The vessel collects bilge water as well as oily rags, filters, bins and other
ship waste and domestic waste generated onboard. Water is separated from the bilge onboard and
thrown back into the river while the used oil is stored free of charge in cisterns and delivered to wastedisposal
facilities onshore.
References
• Waste production of MARPOL Annex V, ship-generated;
• INE (Inland Navigation Europe);
• Waste Management for Inland Navigation on the Danube (WANDA), Recommendations
on Harmonized Europe-Wide; and
• Technical Requirements for Inland Navigation Vessels Resolution No. 61 United Nations.
16 Waste Management Planning for Ship Generated Waste, Journal of Naval Science and Engineering, Volume 1, Number 2, July, 151-159,
2003.