AZ vs. CA:11 California Exhibits, Vol. XI; Nos. 1001-1011; 1101-1109; 1201-1251; 1301-13431301-1343

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Depabtmknt of the Interior United States Geological Subvky, Washington, January SO, 1923. Hon. Cabl Hayden, House of Representatives. My Dear Mb. Haydkk : In reply to your letters of January 4 and 11, and with reference to frequent personal interviews on the subject, I am sending you herewith answers to the questions propounded relative to the Colorado River. Yours very cordially, Philip S. Smith. Acting Director. Question 1. According to your records, what is the maximum, minimum, and average annual floio in acre-feet of the Colorado River between Ynma and Lee Ferry? I would aUo like to have the same information for all of the tributaries of the Colorado River in Arizona where you have a record of stream measurement. Answer 1. The summary of the principal records available for gauging stations on Colorado River and tributaries in the State of Arizona is shown by the attached blue-print sheets. Tlie data given for each station are: The years or partial years of record, the maximum and minimum daily flow and dates of occurrence for each year, the average discharge for each complete year, and the total run-off for each year or partial yenr. The year used is the climatic or water year, beginning October 1 and ending September 30, unless otherwise noted. The iongest continuous record is that for Colorado River at Yuma, which begins with January, 1902. This record is collected by the United States Reclamation Service and furnished to the Geological Survey for publication. The point of measurement is below the mouth of the Oila, so the contribution of that stream is included in the record. The amounts diverted at Laguna Dam are not Included In the record. The maximum year was 1908-9-run-off, 26,100,000 acre-feet; the minimum year wag 1903-4-run-off, 9,870,000 acre-feet. The average annual run-off for 20 years is 17,4550,000 acre-feet. It is of interest to note that the run-off during the year ending September 80,1922, was about 1 per cent greater than the 20-year average. The only records of flow of the Colorado River above Yuma are for one complete year at Lees Ferry, two complete years at Hartyville, and five complete years at Topock. The run-off at Lees Ferry for that year (1921-22) was 16,100,000 acre-feet. The average of the two years' records at Hardyville (1905-6, 1906-7) was 20,150,000 acre-feet. The records at Yuma show that the flow in these two years was 30 per cent greater than the 20-year average. The average run-off of five years at Topock (1917-1922) was 17,860,000 acre-feet. The records at Yuma Bhow that the flow in the five yearn was 6 per cent less than the 20-year average. The run-off in 1921-22 at Topock was 6 per cent greater than the five-year average at Topock. The records indicate that 1921-22 was approximately an average year of run-off. The inflow between I^ees Ferry and Topock for that year, as shown by the records, was 2.9lM).<M)0 acre-feet. There was an apparent Iors of 1,400.000 acre-feet between Topock and Yuma, in addition to the total amount of