Water based epoxy. Something new on the scene but has been around for over a year and well proven.
If you have a section of wood that is wet and spongy, using this product will drive the water out and will firm the timber. It is a two pack product used in three coats.
First coat: Mix epoxy and hardener (1:1) Then dilute with the same amount of water.
Second coat: Mix epoxy and hardener (1:1) Then dilute with half the water.
Third Coat: Mix epoxy and hardener (1:1) No added water.

On the first coat the mix will penetrate and drive out the existing moisture. The other coats will harden the timber.
No thinners required. Brushes wash out in water.

Balcotan is no more. Bought out by Collano and below is new details.

Tried both products by myself and they are excellent.