Pond Boss Forums POND CONSTRUCTION Building a dam repairing spillway wooden gates

photos.

The material that is in front of the existing wood gates is hardboard. It was put in front during a past repair. Up to the bottom of the hardboard (which is bowing out with the water pressure) the remaining boards appear solid. It appears I would have to go down aprox 3-4 feet to do a repair. My question at this point is how deteriorated can I expect the tongue and groove slots to be with the wood that has silt built up against it and how to get the new replacement to seal against the old.

What I have removed is oak but I did find a piece of cedar downstream, maybe from a past washout? Oak or cedar for new ones?

Or should I just use the last slot (photo 9632) and build a new wall