Timber that is fully submerged is not at great risk. Common fungi don't attack saturated wood since they need an adequate supply of oxygen. Timber that is partly under water and partly out of the water is in a more hazardous situation and you would need to choose a durable hardwood in this case, for example tallowwood, ironbark, etc. So your selection of suitable species will depend on the design of the pool and the life span required for the structure.Timber under water
Answered on 19-09-2020
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