Robert Hardy in his book "A Social and Military History of the English Longbow" talks about how bowyers used to cure yew staves by leaving them in streams or moving water for a couple years. I think you have to consider several factors with your wood, such as: was it submerged in moving water, was it shallow water that would likely be filled with critters and fungus when it warmed, was the wood 'continually' under water without any chance of partial drying, and lastly, what kind of tree? I would think your denser, oiler hardwoods would be less likely to have been compromised. It seems like Hardy also mentioned time spent trying to wash the salt out of the staves that went down in the "Mary Rose". You might also have to give consideration to how long the wood should dry out before beginning to tiller and how fast it should be allowed to dry out.
Good luck, keep us posted.
