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<br />. <br /> <br />. <br /> <br />water resources applications. Conduct discussions or meetings as required in this review. <br /> <br />89.2 Obtain and Process Data. Obtain data applicable to current land use as indicated in Table <br />2, including NCWCD irrigated lands and USGS land cover data. The Consumptive Use <br />contractor will provide county agricultural statistics. In addition to the data described in Table <br />2, the Contractor will obtain a series of digital Landsat satellite images for the study area for <br />the cropping season of year 2000. Six image frames will be required for the study area and <br />for each image frame; two or three satellite images will be acquired from different dates <br />during the growing season. Data will be georeferenced, corrected for atmosphere and other <br />influences and preliminarily processed using combined unsupervised and supervised digital <br />classification. <br /> <br />89.3 Determine Irrigated Vs. Non-Irrigated Lands. Initial draft of classification of fields as <br />irrigated or non-irrigated will be based on interpretation of the panchromatic (black and <br />white) DOQQ and IRS satellite image base (Task 90.1), and by referencing the processed, <br />multispectral Landsat images described in Task 89.2. <br /> <br />89.4 Identify Crop Types In Each Polygon. Utilizing commercial image processing software <br />the multi-temporal and multispectral Landsat satellite images will be processed and the <br />Contractor will classify the crop type for each field parcel defined in Task 90.2. County <br />agricultural statistics will be used as a reference. A limited but carefully selected set of <br />ground information will be collected by the Contractor. These data will include 50 field <br />polygons for each major crop type. The primary source of ground data will be the Farm <br />Service Agency's annual delineation of crop types provided by producers on high-resolution <br />aerial photographs, which cover approximately 50 percent of farmlands in the study area. <br />These FSA data will be supplemented with data from ditch companies and irrigators. One- <br />half of these ground data will be used for computer image processing and classification <br />algorithms, and the other half for accuracy assessment as described in Task 89.6. <br /> <br />89.5 Review, Revision and Final Classification. The Contractor will be responsible for review, <br />revision and final classification of results. Instrumental in this process will be input from <br />water users, division engineers, conservancy district engineers and technicians. These <br />personnel will be provided with draft products for use in reviewing the field boundaries, <br />current land use and crop types. Interaction with these personnel for this review will be <br />conducted at the same time as the consultation on irrigation service areas, as described in <br />Task 91, for Districts 64, 1,2 and 3. Based on this review, the Contractor will edit the draft <br />field boundaries and classifications and prepare the final products. <br /> <br />89.6 Conduct Accuracy Assessment. The Contractor will conduct an assessment of the <br />accuracy of classification of irrigation status and crop type. One-half of the field data <br />collected under Task 89.4 will be used to determine classification accuracy and to assess <br />errors. <br /> <br />Deliverables: <br /> <br />89.1 A memorandum describing the final recommended technical approach developed under <br />Task 89.1 for mapping current land use. The memorandum will describe the approaches used <br />in prior DSS irrigated acreage assessments with specific reference to literature. Also, the <br />multi-temporal Landsat satellite imagery to be acquired will be specified. <br /> <br />Page 3 of 26 Pages <br />