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<br />27
<br />
<br />Year
<br />
<br />Acre-feet available for diversion
<br />
<br />First year .......................
<br />Second year.......................
<br />TIlird year. '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '"
<br />F011I'th year. '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '"
<br />Fifth year........................
<br />Sixth year", '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '"
<br />Seventh year. '" '" '" '" .". '" '" '" '" '" '" '" '" '" '" '" '" '" '" '"
<br />Eighth year.......................
<br />Ninth year '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '" '"
<br />Tenth year........................
<br />
<br />1900-64
<br />
<br />1,500,000+
<br />1,500,000+
<br />1,500,000+
<br />1,500,000+
<br />1,375,000
<br />1,220,000
<br />1,075,000
<br />900,000
<br />690,000
<br />365,000
<br />
<br />1945-64
<br />
<br />1,500,000+
<br />1,500,000+
<br />1,500,000+
<br />1,360,000
<br />1,120,000
<br />940,000
<br />780,000
<br />610,000
<br />440,000
<br />300,000
<br />
<br />These are averages for a long period of time, and would occur randomJ,y; con-
<br />
<br />secutive'years as shown above wo,uld be very unlikely.
<br />
<br />Figure 9 represents the chances of.the annual flow being equal to or greater
<br />
<br />than selected amounts. This curve would accurately represent actual experience if
<br />
<br />annual discharges were random events, but they appear not to be, as the flow this
<br />
<br />year has a tendency to be as last year, i.e., there will be several consecutive
<br />
<br />years of more than, or of less than, the average (see figure 7).
<br />
<br />If' it is assumed that the irrigation water available annually at the river
<br />
<br />pumps will be 1,500,000 acre-feet and that the duty should be 2.50 acre-feet per
<br />
<br />acre, then 600,000 acres could be watered. Table 17 shows the number of acres that
<br />
<br />Table 17.- Irrigated acreage for selected allocations.
<br />
<br />Acre-feet Irrigated acreage in 1,000's, for
<br />available annual allocations in acre-feet uer acre of-
<br />for 1.6 2.0 2.4 2.8 3.2 3.6 4.0 4.4 4.8 5.2 5.6 6.0
<br />irrigation
<br />1,200,000 750 600 500 429 375 333 300
<br />1,300,000 812 650 542 464 406 361 325 295
<br />1,400,000 875 700 583 500 438 389 350 318 292
<br />1,500,000 938 750 625 536 469 417 375 341 312 288
<br />1,600,000 1,000 800 667 571 500 444 400 364 333 308 286
<br />1,700,000 1,062 850 708 607 531 472 425 386 354 327 304 283
<br />1,800,000 1,125 900 750 643 562 500 450 409 375 346 321 300
<br />1,900,000 950 792 679 594 528 475 432 396 365 339 317
<br />2,000,000 1,000 833 714 625 556 500 455 417 385 357 333
<br />2,100,000 1,050 875 750 656 583 525 477 438 404 375 350
<br />2,200,000 1,100 917 786 688 611 550 500 458 423 393 367
<br />2,300,000 958 821 719 639 575 523 479 442 411 383
<br />2,400,000 1,000 857 750 667 600 545 500 462 429 400
<br />2,500,000 1,042 893 781 694 625 568 521 481 446 417
<br />
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