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Show 476 time comes when the river ceases to build the bar higher and on the contrary, begins to excavate a trench through that bar, which will eventually become the low water channel. " The amount of excavation may be very considerable. I saw bars along the Colorado river where it is quite certain that the excavation reached four or five feet. In the case of the Arkansas river, I have come in contact with cases where it probably reached twelve or fifteen feet. " In the Mississippi river, for a few miles below St. Louis, which I have inspected, although I have never been officially in charge of it, they consider that a bar which during the freshet stage does not build higher than the low water surface will cause no worry during the subsequent low water season. " In other words, a river will excavate at least nine feet through that bar. " In general terms , where the river is curving to the left, the deep water will be in the concave bond, close to the bank. [ R. 1220] " For the trip on the Colorado river we adopted the plan that we wold travel as close to that bank as seemed safe, in view of the boulders and rocks that had fallen off the cliffs into the edge of the river. " As you leave a bend turning to the left, you are following the right bank, and as you enter the straight reach, the deep channel ordinarily follows down the right |