Fluid and wave dynamics are quite predictable if you know what causes the lines and how they interact.
The 'lines' are as a result of energy transmission through the surface of the water. They move independently through each other from different sources, giving the criss-cross pattern. The static waves at the edge ai when the speed of transmission is equal to the flow of water in the opposite direction. Surfers often use this at river mouths when the tide comes in and the water rushes out. The static wave can last for quite some time. Drag against the side of the channel will slow the water flow dramatically which results in the formation of eddies. Enough eddies will result in the turbulent effect.
It really all bout energy.
And, yes, I find it quite mesmerising as well.