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Show Record was 1.91 for this year. The San Juan carries less water than either Cisco or Green river, so it is much muddier. The Colorado River at Lees Ferry has a percentage of .64, nearly the same as the percentage at Greenriver, but the flow at Lees Ferry is a little over three times the flow at Greenriver, so it is clear at Lees Ferry. At the Bright Angel Station in the Grand Canyon the load was 152,000,000 tons for the year. In considering the quantities I have mentioned , only 3809 solid matter in suspension has been take into consideration. In computing the quantity of material carried in solution. That is an entirely different proposition. When the velocity of the river becomes sufficiently slow, the suspended matters are deposited. On the rivers hereiin question 3810 I could not predict when deposition would take place, because the factors controlling the amount of material carried by the river are slope, velocity, kind of material carried and quantity carried. For a given velocity, you may find that the river is carrying at one time only a very small proportion of suspended matter; whereas for a velocity that is practically the same, or a little large, it may carry many times that amount of material. In that case, it is probably a question of how much material is available. The term " Bed Load". as I use it, it one that Gilbert introduced in his work on the " Transportation of Debris by Moving Water". He referred to a certain amount of material that is transported along the bed of the river and it is in that way that I refer to material along the Colorado River and its tributaries that we do not get in our suspended matter samples. Some of it is 3811 rolled along the bed; probably some of it is in suspension. It is the material that does not get very far away from the bed. The terms " scour" and " fill" are applied to changes in the level of the river bed, It is a kind of continuous process, always changing. 546 |