Operação integrada do reservatório Engenheiro Arcoverde, poços amazonas e perímetro irrigado de Condado-PB, utilizando-se de programação linear.

Abstract

In this work, the optimal operational releases from Engenheiro Arcoverde reservoir and the pumping of water from the downstream amazon type of wells and the selection of the areas of irrigated crops, located in the neighborhood of the Condado town, within a semi-arid region of the Paraiba state, are studied in order to maximize the net profit. The main scope of this work is to provide the engineer with a methodology and tool to design and plan more efficient uses of water within a (semiarid region) (region with scarcity of water). A linear programming method developed by Curi and Curi, 1998, was used herein to achieve an optimal solution for the problem. The natural nonlinearities of the problem are also considered in a recursive way. The linear equality and inequality constraints are characterized by the physical and crops' phenological behavior and limitations, socio-economical and legal requirements and the guarantee of the sustainability of the system within a time period. The decision variables are the irrigated crop areas and the monthly water volume released from the reservoir and pumped from the downstream amazon type of wells used for each type of irrigated crop. The objective function is the net profit attained from each irrigated crop production, selling prices and managerial costs. Several scenarios, which were characterized by a set of selected five-year hydroclimatic time series data gathered from a 2 0 years time period and defined as medium, normal, dry and wet seasons, were considered. It is also compared the proposed solution of the model with an experienced situation, for the same hydro-climatic conditions, during the years of 1996 and 1997 The attained results for the decision variables as well as the optimal operational policies for the reservoir releases are dependent upon the hydro-climatic scenarios and the reservoir initial and final required storage conditions. Besides running the program for several scenarios and providing the sensitivity analysis with respect to several parameters, it has also been shown, when comparing the attained results with a real world situation, that the net profit can be improved if appropriate managerial decisions are taken. It has also been shown that it is possible to determine, with the proposed model, optimal monthly reservoir storages, for some proposed scenario, that maximizes the net profit while it is guaranteed the sustainability of the system.