Wood from a vast underwater forest in Ghana could be used to rebuild Notre-Dame Cathedral after its spire and roof were consumed by a blaze in April.
Massive tropical trees have been submerged beneath Lake Volta since 1965, when the construction of Ghana's Akosombo Dam flooded part of the Volta River Basin.
A Ghanaian company, which has government concessions to harvest this wood, believes that using it to rebuild Notre-Dame is more environmentally friendly than cutting down new trees.
Kete Krachi Timber Recovery argues that the wood is "much stronger" because it has been preserved from decay by the lake's bog-like conditions, and has started to fossilise.While some experts have described the proposal as a "genius solution", others warn that it could have disastrous consequences for the ecosystem.The company has submitted its proposal to the French government, arguing that using wood from Lake Volta would help restore Notre-Dame to its original state.
An estimated 1,300 trees, mainly oaks, were felled in the 12th Century to build Notre-Dame's iconic frame and spire. The deforested area spanned 52 acres - the equivalent of 26 football pitches.
According to Bertrand de Feydeau, vice-president of French preservation group Fondation du Patrimoine, France no longer has giant oak trees of the same size and maturity that were used to build the original structure.
Francis Kalitsi, chairman and co-founder of Kete Krachi, agrees. "We don't think they still have oak in these volumes for the construction of cathedrals," he said.
"Whereas underneath the lake, you have typical African hardwoods that are similar to oak trees - their density may range from 650kg to 900kg per cubic metre. They are structural timbers which could be useful in the reconstruction."
Kete Krachi already harvests the underwater timber using remotely operated machinery guided by video, sonar and GPS navigation. Most of the wood is exported to Europe, and some to South Africa, Asia and the Middle East.
The company says if commissioned, it would sell $50m (£39.5m) worth of wood to the French government. Its proposal has already been acknowledged by the ministry of culture.
Jérémie Patrier-Leitus from the French culture ministry told the BBC: "Right now we don't know if the frame will be rebuilt in wood. We are in the process of securing the monument, and then we will have to rebuild the vault and the spire.
"Reconstruction will start once the structure of the monument is stabilised and preserved. We will study the different generous offers once we have confirmed the material used to rebuild the frame."
Bog oak: A more durable wood
Dr Cathy Oakes, specialist in French and English medieval architecture and iconography at the University of Oxford, said the wood in Lake Volta could be similar to "bog oak", which was widely used in medieval constructions and furniture, although not in the original Notre-Dame.
"Bog oak has similarly been exposed to water for a long period of time, so it's stronger and more durable," she said in remarks before her death this summer.
The shortage of oxygen, and the acidic conditions of peat bogs and riverbeds help to preserve tree trunks from decay. The wood then begins to fossilise, making it significantly stronger.
Andrew Waugh, director of London-based sustainable architecture practice Waugh Thistleton Architects, said using African wood such as iroko from Lake Volta could be a "genius solution".
This Article was originally seen a t https://www.bbc.co.uk/news/world-africa-48964785