Although appearing natural and un-decayed, water logged wood quickly deteriorates. In order to stop this, the wood is currently being treated in tanks filled with a chemical called Polyethylene glycol. (PEG)
This gradually replaces the water in the wood and helps to protect it from decay and warping when it's dried.
Prior to this, the Timbers were in a solution containing 2% Ammonium Citrate. This solution helped to draw out any iron remaining in the timbers from various nails and clasps. Should these traces of iron have remained in the timbers, they would have increased the rate at with the wood deteriorated following conservation due to chemical reactions with its surrounding environment.
The timbers have now been going through these processes for several years.