Ship detained after discharging oil in Manila Bay.

The MT Makisig, a 34 000 barrel (5.4 million liter) double hulled oil tanker, owned by the Herma Shipping and Transport Corporation and chartered by Chevron Philippines Inc, has been detained by authorities in the Philippines after discharging around half a million liters of diesel into Manila Bay on Thursday 8 August 2013. It is unclear why the incident happened, as the ship had earlier unloaded its load of fuel oil at the Petron Rosario Terminal, apparently without incident, and was leaving the bay at the time of the discharge. Discharges of this kind are often associated with cleaning out the ship's bilge tanks, areas at the bottom of ships hulls where waste liquids accumulate, including waste oil from engines and any oil that has leaked from tanks internally. Legally this must be carried to a port, adding to a ships fuel bill, then washed out by properly trained contractors and any waste material properly disposed of, again costing money. If a good reason cannot be provided for the discharge, then the ship's owners can be asked to pay the costs of cleaning up the spill, and its crew may face criminal charges.

The MT Makisig, detained in Manila after discharging around half a million liters of diesel into the sea. Shipbuilding Tribune.

The Philippine Coast Guard have attempted to contain the spill with a series of booms, but due to the size of the slick, which covers around 300 km², it is not confident of complete success. As diesel is a light oil, and will evaporate over time, authorities in Manila have decided not to use chemical dispersants on the spill, which can cause further environmental problems, being themselves persistent in the environment and toxic to wildlife. Around 20 km of shoreline has apparently been affected by the spill, which is also spreading towards the mouth of the bay. A number of people have been hospitalized with breathing difficulties associated with fumes from the spill, and the Fisheries and Aquatic Resources Bureau has banned the harvesting of shellfish from affected areas until further notice, due to the toxic nature of the oil.

Manila Bay and the surrounding area. Google Maps.

The MT Makisig was originally designed as a single-hulled tanker, and retrofitted by Herma Shipping at its shipyard in Mariveles, Bataan, in 2012. Herma have also began to build double hulled vessels from scratch, and have been keen to publicize their role as the first company in the Philippines to do so. As such this incident is likely to harm the company's image, regardless of whether it was caused by criminality or a technology failure.

See also Oil dumping causes 16 km slick in the Arabian Gulf, Stricken tanker spills fuel oil in Ternate port, North Maluku Islands, Oil spill devastates popular Thai tourist resort and Nigerian sailor survives two days in sunken oil service vessel, Collision leads to oil spill on swollen Mississippi.

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Oil dumping causes 16 km slick in the Arabian Gulf.

A ship has been observed dumping oil in the Arabian (Persian) Gulf, according to the Marine Emergency Mutual Aid Centre, an intergovernmental agency representing eight nations on the Gulf, which is credited with having achieved a 90% drop in oil-related pollution in the region since 1999. The Indian registered Desh Shanti, a 158 000 tonne double-hulled oil tanker, was observed dumping oil in Iranian Waters, and persisted despite warnings from authorities, resulting in a 16 km slick which threatens the coasts of Iran and neighbouring states, who are monitoring events closely. 

The Indian registered Desh Shanti, accused of dumping oil in the Arabian Gulf. Shipspotting.

The Marine Emergency Mutual Aid Centre has recommended that any nation affected by the spill take legal action against the vessels owners, The Shipping Corporation of India. Since the dumping took place in Iranian waters Iran could potentially impose fines of up to US$1 million on the vessel, but other nations potentially affected could also seek legal redress. The vessel has also been reported to the International Maritime Organization, which keeps a black list of vessels involved in illegal activities, and raised with the Indian Government.

The exact reason why the Desh Shanti was dumping oil is unclear, but this activity is usually associated with cleaning out the ship's bilge tanks, areas at the bottom of ships hulls where waste liquids accumulate, including waste oil from engines and any oil that has leaked from tanks internally. Legally this must be carried to a port, adding to a ships fuel bill, then washed out by properly trained contractors and any waste material properly disposed of, again costing money. Dumping oil from the bilge tanks into the sea is clearly a much cheaper option, but was banned by the International Convention for the Prevention of Pollution of the Sea by Oil in 1954, leading to a steady reduction in the practice around the globe as local authorities developed ways to enforce the ban.

Sea also Stricken tanker spills fuel oil in Ternate port, North Maluku Islands, Oil spill devastates popular Thai tourist resort, Nigerian sailor survives two days in sunken oil service vessel, Collision leads to oil spill on swollen Mississippi and Oil barge explosion in Port of Lagos.

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