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3726 that every rancher on the High plains worth his salt is engaged in erosion control prac- tices designed to reduce erosion and so reduce the silt burden of the waters reaching the river. It should be noted that the water at flood stage carries much higher relative silt load than water not at flood stage by reason of the fact that flood waters are the products of deluges or downpours and that the signifi- cant silt deposition above the dam are those depositions made during periods of storage when the river is at flood stage. It should be pointed out that the place of deposition of this silt is important. I Assume a permanent pool and the onset of a flood involving storage, the permanent pool will provide a buffer of clear water initially two miles thick and gradually narrowing as the reservoir fills which will result in a deposition of the flood silt burdens upstream, away from the dam, instead of against the dam and in front of the gates. It is submitted that this will be a significant advantage and savings to the future operation of the facility. How realistic is this concern for the increased depositions of silt above the dam? Some of the variable factors have already been enumerated. What will the silt burden of the natural stream flow be when the river is low? How effective a sediment trap will the permanent pool be? What is the total volume of water passing through the dam at this time? In other words, I think there are three variables: the volume of water that would pass through the dam when the river was on priorities; the silt burden which I submit would be significantly less than the silt burden of the stream at flood stage; and the effectiveness of the pool as a sedi- ment trap. Viewed as such, it would appear to me that the problem of silt deposition would not be significant in volume; that its deposi- tion upstream, away from the dam, might well lengthen the life and the effectiveness of the facility. I