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001135 -17- 14. Diversionsl Available records of diversions by Project canals go back to 1913. A summary of the seven project oanals and the prinoipal lateral from the South Canal (Table 8) shows that for the 29-year period 1913- 1941 diversions averaged 362,800 A.F. per year. The project was not oomplete at the time the diversion records start, and diversions as of 1938-41 are a litt]a over 100% greater than in 191,-14. Althou[;h the project was oonsidered to be praotioally complete by 1925, there has been some increase in diversions in rooent years. Some of this apparent increase is due to the fact that the Projeot received water from Taylor Park Reservoir in 1939, 1940 and 1941. Di. versions have not dropped be- low 400,000 A.F. sinoe 1935, and in the ten years prior to that had only been above that amoulIi:; in three years. Study of the ten-year averages indioates that diversions were inoreasing until about 1919. and from that year through 19,8 they were quite stable. The years 1939-41 have oaused an upturn in the la-year averages. In order to get a complete pioture of diversions in the lov.er Unoompahgre area it is necessary tc add three i tams to the 362.800 A.F. shown in Table 8. llAIN VALLEY DIVERSIONS 1913-41 Diversions of Principal Canals Diversions of South Canal Laterals Diversions of private Canals Diversions to Study Area from Tributaries (Inoludin~ By-passed Amounts at Colona) 362,800 29,000 ,4,000 47,000 Total Colona to Delta Diversions 472#800 This f"igure of 472,800 A.F. per average year is an approximate value for the 29-year period 1913-1941. The estimate of diversions by South Canal laterals is based on a study of measurements at various points along the South Call8.1 together with the ealoulated canal loss val- ues as determined by the Bureau of Reolamation. Diversicns for private canals was obtained from the 1938-19!~ records of the Water Commissioner, assuming that there has been little change in this value durinG the 29 years. The third item is an estimate of the amount of tributary water entering the area, based on the records" obtained during 1938-41 and com- pared to the long tilne runoff record at Colona. The assumption is that the water entering the area from tributaries oan be oonsidered as a di- version from those tributaries. To oarry the analysis of divcrsians further, it is evident from the reoords that the diversions during the period 1919-1937 had reached an approximate normal oondition (that is. had reached a probable