Forgive the stupid question...

Blackfeather

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www.blackfeatherboatcharter.com
As a new boy here I hope I will be forgiven for asking stupid questions...

With the current flooding in mind, what is the effect on depths once the levels return to normal? Does it 'scour' the river bed thereby increasing depth or does it shift silt and create shoals, or both?
 
All of the above, it will scour where the water is fast (below a weir for example) and deposit where the flow is less.(inside of a bend).
 
Wellllll

Fast moving water erodes the channel, slow moving water deposits silt. Fast moving water tends to straighten a water course, slow moving and the water meanders about.

Providing there is no flow restriction downstream then once things return to 'normal' ie. the *volume* of water is back to where we started then the actual depth of the water will stay the same! It's just that its surface will be lower. ie. The Grand Canyon has a big river at the bottom but the hole it's made is not full of water!
 
Wellllll

Fast moving water erodes the channel, slow moving water deposits silt. Fast moving water tends to straighten a water course, slow moving and the water meanders about.

Providing there is no flow restriction downstream then once things return to 'normal' ie. the *volume* of water is back to where we started then the actual depth of the water will stay the same! It's just that its surface will be lower. ie. The Grand Canyon has a big river at the bottom but the hole it's made is not full of water!

As the water level is maintained by locks/weirs in a river it will not be lower than it was, the areas scoured by flow Will be deeper !
 
Rough rule of thumb: The river gets deep where it's already deep, and shallower where you need it to be deep...
 
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