Resumen
The present investigation this focused in evaluating the methodologies used in the Nineties in projects of agricultural type, particularly in the districts of irrigation, by identify the theoretical and technical and operative strengths and weaknesses in the aspects financial, economic, social and enviromnental. From a selection ofthe projects of greater spread implemented by the agricultural sector during this period the evaluation ofthe methodologies is made from a set oftheoretical norms standard in the evaluation ofprojects, which allows to identify the technical strengths and weaknesses in the evaluation of these projects. The results of the study show that in most of the analyzed projects, technical deficiencies in the matter of essential parameters like the rates of discount and there is not use ofshade prices. Also the projects do not involve the enviromnental costs in the cash flows, which artificially affects the reality of the valuation of same project making them more profitable in terms of an international comparison. In the same way, the social valuations are practically nonexistent and therefore it is not possible to evaluate the impacts on the well-being and the social utility. On the data bases ofthe most important Project (Ariari) undertaken by the agricultural sector for this period, the aspects of measurement and quantification of the risk are gotten up, finding technical benefits when combining financial methodologies.