I have one area I need to do something with and it has it's own unique problems. I don't have a picture of it but it looks kinda like this, except the fence along the river is not the nice neat looking thing in this drawing.
This is a narrow deep ravine that is the culmination of my pond's overflow channel and it joins the river channel about 20' beyond the fence.
Most of the time the ravine is dry.
In heavy rains, the water goes under the fence into the river,
but if it's a long period of rain, the river rises and starts backflowing into the ravine & pond overflow...the pond itself is about 1500' up the channel.
If the river continues to rise (It does sometimes get over the fence itself) then the flow in the whole area is from left to right in the drawing.
I've never lost the fence here, but I have had calves get down in the ravine in dry times and walk out under the fence into the dry part of the river channel. I need a baffle that will swing both in and out but won't get carried away down river once the flow is left to right over the whole thing. I had a strand of SS cable on crosstie posts with old tires threaded onto the cable but it and the crossties got swept away long ago.
Can't put a big post in the bottom of the ravine because it would catch too much debris.
???
There are a few trees nearby, but not close.
Top and cross section views