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o (~ c - Land and Irrigation Development Sources of Data There has been little land development within the project area in recent years. Chronically short water supplies resulting in low yields and small economic returns have provided little incentive for the expenditure necessary to improve and further develop project lands. Consequently, there are no data available relating directly to development costs on the project lands. All estimates have been based on requi rements of similar so ils in other areas that are somewhat comparable in site conditions but with better water supplies. Cost estimates are based on the U.S. Department of Agriculture pri ce pro jections of September 1957. Analysis of Data Soil and site factors and climatic limitations restrict the amount of development that is physically or economically feasible on project lands. The steep slopes and shallow soils that are characteristic of the area restrict crops to those which provide a permanent cover except on the most erosion-resistant lands. The same factors result in the lower irrigation effi ciencies that can be attained wi th the labor inputs associated wi th the expected levels of management. The projected level of development under project conditions is rather low, generally, and is based both on the level of management expected in the area, and on'the physical requirements of the soils. Irrigation efficiency estimates reflect this level of development and management. They are higher than exist under present condi tions on the project lands, but are readily attainable with the projected addi tional inputs of labor and the altered pa tterns of water delivery that will accompany project construction. Land Clearing Native cover varies qui te widely wi th elevation and location on the project. It ranges from pinon-juniper type on the higher fringes of evaluation area A, to a sparse growth of low sagebrush and associated brushy plants on Grandview Mesa that are included in evaluation areas C and D. Clearing costs have been estimated largely in relation to the predominate cover existing on lands wi thin the various evaluation areas, and in accord wi th costs incurred in similar areas of southwestern Colorado. Land Leveling Land leveling is defined as "the reshaping of the land surface to a planned grade to permit the uniform distribution of irrigation water without erosion, or to provide necessary surface drainage. II This does not imply the removal of slope or gradient from the land surface but, rather, the elimination of surface irregularities which impair the uniform application of irrigation water, or occasionally J the terracing of the land to permi t irrigation on flatter, transverse slopes. - 17 - ,I I , I