The green pipe sticking out from under the AquaDam® is for over flow.
If water builds up too high behind the AquaDam®, the water will run
under it and through the pipe provided.
This is the intake side of the over flow pipe. This pipe (providing you
have the right size for the amount of water that will be passing through
it) will keep the AquaDam® from washing out and keep the water level at a
manageable height.
