There is a state owned 70 acre lake in my area that is 20 feet deep max. They have a flashboard riser for the primary spillway and have 2 x 12's for the boards. The lake has been there for 80 years. The water level at the riser is approx 4 foot and last year there was 26 inches of ice on the lake. I was talking to the Conservation officer and he said they used waterproof caulking between the boards to prevent leaks. It flows large quantities of water over it with no problem.


Dreaming of the pond!