Underwater heritage

A wreck is a time capsule: a sunken ship carries with it its cargo, its everyday objects, its navigation instruments and, often, its secrets. Underwater conditions sometimes preserve organic materials remarkably well, such as wood or textile, which disappear on land.

If the site is damaged by looting or a poorly conducted excavation, this information is lost for ever. That is why archaeologists consider that underwater heritage should, as a priority, stay in place, with as little intervention as possible.

The 2001 UNESCO Convention on the Protection of the Underwater Cultural Heritage lays down four principles: the obligation to preserve, the preference for in situ conservation, the prohibition of commercial exploitation and cooperation between States. About seventy States have ratified it.

The law of the sea, the sovereignty of the flag State, the rights of the coastal State and the rules of maritime salvage come on top, with tensions at times. OIMAP helps its members to fit these texts together.

Objects from wrecks regularly appear on the market: ceramics, coins, instruments, cannon, tableware. Their origin is often hard to establish, because looters document nothing. The 2001 Convention prohibits their commercialisation, but some States do not recognise it.

OIMAP asks operators for particular vigilance: demand proof of the date and place of discovery, check the excavation permit and refuse objects from protected sites. The BIOP database lists known looting.

Underwater heritage belongs to humanity. Underwater museums, supervised dive trails and digital exhibitions let the public discover it without destroying it. These initiatives also create jobs and income for coastal communities.

OIMAP supports these projects and encourages States to involve divers, fishers and residents in monitoring: they are often the first to discover or report looting.