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<br />3369
<br />
<br />FACTOR 4, AREA TO BE IRRIGATED
<br />
<br />Pan 417,3 identifies the area to be inigated as a factor to be analyzed, The estimate of
<br />the annual area to be irrigated within lID in 2003 is based upon the Monthly Crop
<br />Reports and Annual Inventories of Areas Receiving Water provided by lID, These lID
<br />data serve as the basis of estimates of lID's irrigated acreage utilized in the following
<br />technical reports: Jensen/Walter 2002, p, 33, Appendix A; NRCE 2002, p, III-I 0 and
<br />Appendix 6C & 60; and WAC: Gilley et a!. 2003, p, 70,
<br />
<br />These lID data represent information reported on the basis of land parcels and used by
<br />lID to identify the number of acres of crops including those areas of land with year round
<br />crops, such as alfalfa and bemlllda grass, and areas where multiple or rotatlOn cropping
<br />(double and triple crops on the same parcel of irrigated land) is practiced, such as for
<br />vegetables and sugar beets, The number of in'igated acres is determined from these data,
<br />
<br />Historic information relating to irrigated acreage within lID is available for a long period
<br />of years (Jensen/Walter 2002 Appendix A; WAC: Gilley et a!. 2003, p, 70, Figure IV,14;
<br />and NRCE 2002, Appendix 6C & 60), For this determination, the time period of 2000 to
<br />2002 was selected to reflect the most current irrigated acreage experience (Jensen/Walter
<br />Supplement 2003, p, I), Further, to evaluate any recent changes in the trend, acreage
<br />monthly reports from lID through April'2003 were also reviewed (Jensen/Walter
<br />Supplement 2003, p, I), This analysis did not indicate any significant change in irrigated
<br />acreage from previous years,
<br />
<br />The following tabk: summarizes the 2000 to 2002 crop data provided by lID in its
<br />Monthly Crop Reports and Annual Inventories of Areas Receiving Water. The table
<br />shows how adjustments for multiple cropping acres are used to derive the area to be
<br />irrigated each year. The Adjustment for Multiple Crops is deducted from Total Crops
<br />because, in most instances, multiple crops are sequentially grown on the same acre of
<br />land during the course of the year,
<br />
<br /> 2000 2001 2002
<br />Total Crops (ac) 537,076 521,847 508,44 I
<br />Adjustme nt for
<br />Multiple Crops (ac) 75,562 68,664 55,533
<br />T otalllTigated Area (ac) 461,514 453,183 452,908
<br />
<br />Reclamation also analyzed satellite imagery as a confimling piece of data Identifying
<br />recent irrigated areas withm liD (Milliken 2003), Use of this satellite analysis identified
<br />approxlInately 430,000 cropped acres, excluding roads and all other non-cropped areas,
<br />liD data are reponed on a land parcel basis and not on the baSIS of cropped area and IS
<br />
<br />July 2, 2003
<br />
<br />18
<br />
<br />Detenninations and Recol11mendaliors
<br />For liD - Calendar Year 2003
<br />
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