| OCR Text |
Show Record Complainant's Exhibit No. 493, being Water Supply Paper 636- A, " Quality of Water in the Colorado River from 1926 to 1928", was received in evidence. I also prepared Water Supply Paper No. 636- B, " Suspended Matter in the Colorado River, from 1925 to 1928". This paper con-tains the results of our studies on the silt samples and water samples from all of our gaging stations through September 30,1928. Complainant's Exhibit No. 494, being Water Supply Paper 636- B, Suspended Matter in the Colorado River, 1925 to 1928, by C. S. Howard, was received in evidence. This years reports have not been published. I have a summary of the different stations and will read them into the record. Figures for the silt samples were not available for all these sta-tion, so I have based these quantities on the quantities I found in the water samples, and, as I said before, these quantities are a minimum rather than the total quantities carried, because of the nature of the samples taken. At Greenriver, Utah, the Green River carried a total of 3803 fifty million, seven hundred thousand tons for that year. The year ending September 30, 1929. I mean that during the year there were fifty billion, fifty million, seven hundred thousand tons of solid material carried by the Green River past our gaging station at 3804 Greenriver, Utah. That calculation is based upon the observations which have been made from time to time of silt and discharge. Of course, in making an estimate of that kind there is a certain amount for error that enters into it. I have not made any allowance for error. There are two ways in which this figure is conservative. In the first place, this quantity is based on water samples which were taken where the quantity of suspended matter is not representative of what has occurred in the main body of the stream. In the second place, I have based this on a straight 3805 mathematical average of all the samples that I had. The method which I adopted of computing suspended matter is an approved method among scientific men, and is recognized by my department as the |
