I don't think that would be free from deposits left by ducks, fish, etc.
Missippi flood waters
I don’t think that would be free from deposits left by ducks, fish, etc.
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All true. After treatment, this would be a great source for higher end municipal and lower end farm water.
But even then it would be better to drain the tributaries of the Mississippi at flood from march to june than to slice off 10-20 feet of the Mississippi River itself because I imagine that river is pretty toxic.