One half of the attachment collar can be seen floating in the lake. The other half is around the last 15' of the filled AquaDam®. Both being white, it is hard to tell the outside skin of the white AquaDam® from its white collar. Notice the two fill tubes coming out of the collar on the black AquaDam®.   

You can see the exposed mud flat after dewatering this side of the lake. Notice the lighthouse in the left side of the picture. After initial dewatering, only one pump, left on idle, was used to keep the water completely drained off to allow for excavation and removal of sediment.

Overview of the dewatering. 

Overview of the dewatering.