Laserfiche WebLink
<br />301j <br /> <br />. <br /> <br />Irrigation requirement <br /> <br />Effective precipitation during the groWing season was computed <br /> <br />by months based on percentages of effectiveness applied to increments <br /> <br />of monthly rainfall as outlined in Reclamation Manual Volume IV, <br /> <br />Water StUdies, Part 4, Chapter 4.1.13. Monthly effective precipi- <br /> <br />tation was totaled for the groWing season and deducted from the <br /> <br />annual consumptive use requirement in order to derive the annual <br /> <br />crop irrigation rec<.uirement. Annual crop irrigation rec<.uirements <br /> <br />using this procedure deviated a maximum of only 0.04' from annual <br /> <br />crop irrigation rec<.uirements derived by deducting monthly effective <br /> <br />precipitation from monthly consumptive use requirements. Precipi- <br /> <br />tation records for the Hoehne station were used for the 1937-1948 <br /> <br />. <br /> <br />period and precipitation records at the Trinidad C .A.A. Airport <br /> <br />near Hoehne were used for the 1949-1957 period. Trinidad precipi- <br /> <br />tation records for the period 1925-1936 were corrected to the Hoehne <br /> <br />area by a correction factor of 82.8 percent determined by comparison <br /> <br />of precipitation data from a U.S. Weather Bureau publication, <br /> <br />"Climatological Summary of the United States--Supplement for 1931 <br /> <br />through 1952". The basis for tl:tis as follows: <br /> <br />Trinidad mean annual precipitation <br />for period of record. . . . . . <br />Hoehne mean annual precipitation <br />for period of record. . . . . . <br /> <br />16.83" <br />13.94" <br /> <br />Table 5 shows effective heat units, consumptive use rec<.uire- <br /> <br />ments, effective precipitation and crop irrigation rec<.uirements <br /> <br />during the groWing season for each year of the 1925-1957 study <br /> <br />. <br /> <br />period. <br /> <br />2J. <br /> <br />