Hi Ray76, "Turbulent, 'non-laminar flow point' causing a notable 'bump' in Upper Main Spillway high volume waterflow" - There has been discussion going on in another engineering site concerning the inlet turbulence to the main spillway (i.e. scouring of the inlet or simple non-laminar inlet flow discussion).
What was missed was in their photo was the discovery of the notable "Turbulent Crest" in the flow some couple of hundred feet behind the concrete weir in the main spillway.
note: "Turbulent Cresting" requires a convergence of directed flow -or- in rivers, usually from a non-laminar base (such as a subsurface body). In addition there is a symmetrical presence of spray water on the far containment wall - which is centered at this focus "cresting point"...
It would be best if this powerful turbulent point (non-laminar flow) is simply from an asymmetric inflow condition (circled). I don't have a peak height/width of this turbulent crest zone at the moment. Note: this shot has been "image sharpened" via processing software for zoom & contrast clarity (compare to full size view in your original post).
