CB1 that is exactly what is happening in the pics above. The wind is coming uphill from behind the dam and hitting it and acting as a wind break at low level. Winds a little higher which are unimpeded hit the water and points. Mass confusion results with winds going in all different directions and causing cross currents in the air and water including whirling aeration effect where the currents cross or parallel the banks.

Lou the close one is a long peninsula. We wanted an island but there was to much rock that would have required way to much explosives to break.