Environmental Law & Policy

Strait of Malacca

The Strait of Malacca, located between Indonesia, Malaysia, and Singapore, links the Indian Ocean to the South China Sea and Persian Gulf. The length of the strait is about 800 kilometres. At its narrowest point in the Phillips Channel of the Singapore Strait, Malacca is only approximately 1.7 miles wide, creating a natural bottleneck, as well as potential for collisions, piracy, grounding, or water pollution, particularly for oil spills.


The International Hydrographic Organization defines the limits of the Strait of Malacca as shown by the dashed lines on the map below. However, for practical purposes, many include the Singapore Strait as part of Malacca.

Base map source: Demis

Importance for Oil Transportation

Malacca is the shortest sea route between Persian Gulf suppliers and the Asian markets—notably China, Japan, South Korea, and the Pacific Rim. Oil shipments through the Strait of Malacca supply China and Indonesia, two of the world's fastest growing economies. It is the key oil transit chokepoint in Asia with an estimated 15.2 million barrels per day passing though the Strait in 2011, compared to 13.8 million bbl/d in 2007. Crude oil makes up about 90 percent of flows, with the remainder being petroleum products.

Over 60,000 vessels transit the Strait of Malacca per year. If the strait were blocked, nearly half of the world's fleet would be required to reroute around the Indonesian archipelago through Lombok Strait, located between the islands of Bali and Lombok, or the Sunda Strait, located between Java and Sumatra.

caption Strait of Malacca from space. Source: NASA Mission ISS022 There have been several proposals to build bypass options and reduce tanker traffic through the Strait of Malacca, but most have not been followed through. China is on schedule to complete the Myanmar-China Oil and Gas Pipeline in 2013, two parallel oil and gas pipelines that stretch from Myanmar's ports in the Bay of Bengal to the Yunnan province of China. The oil pipeline will be an alternative transport route for crude oil imports from the Middle East to potentially bypass the Strait of Malacca. The oil pipeline capacity is expected to reach about 440,000 bbl/day.

Impediments to shipping

At its narrowest point in the Phillips Channel of the Singapore Strait, Malacca is only 1.7 miles wide creating a natural bottleneck, as well as potential for collisions, grounding, or oil spills. According to the International Maritime Bureau's Piracy Reporting Centre, piracy, including attempted theft and hijackings, is a constant threat to tankers in the Strait of Malacca, although the number of attacks has dropped due to the increased patrols by the littoral states' authorities since July 2005.

Beyond the intrinsic narrowness of the Strait of Malacca, there are two chief significant shipping hazards: historical piracy that continues into the 21st century, and severe air pollution haze. Pirates operate from the shores of the Strait of Malacca preying on ship traffic in the narrow parts of the strait; in modern times, most of these raiders have been based in Indonesia. Slash-and-burn practises on Sumatra generate continuing severe particulate haze, that makes the narrow shipping lane even more hazardous, due to impeded visibility. 

Ancient history

The thallasocratic empire of Srivijaya on Sumatra acquired control of two key marine choke points: the Strait of Malacca  and Sunda Strait. The Srivijaya Empire exerted dominance in this region from about 750 to 1200 AD.


  • World Oil Transit Chokepoints, Energy Information Administration, 2013
  • Limits of Oceans and Seas, 3rd edition. International Hydrographic Organization. 1953.
  • U.S. Central Intelligence Agency World Factbook
  • Clarksons
  • Eastern Bloc Research
  • International Energy Agency (IEA)
  • International Maritime Bureau
  • Lloyd's List Intelligence
  • Paul Michel Munoz. 2006. Early Kingdoms of the Indonesian Archipelago and the Malay Peninsula. Didier Millet. Singapore ISBN 981-4155-67-5.
  • Panama Canal Authority
  • Petroterminal de Panama, S.A.
  • Suez Canal Authority




Administration, E. (2013). Strait of Malacca. Retrieved from http://www.eoearth.org/view/article/51cbfba07896bb431f6bff36