Custo da água com vistas à sustentabilidade dos sistemas urbanos de abastecimento.

Abstract

The general goal of this thesis is to establish a model to identify the water rate charged by Brazilians sanitation companies that privileges sustainable water supplies systems considering financial, economical, social and environmental criterions. The justification of this study is originated from the necessity of new entrepreneur’s strategy and management proposals that can be a match for the new competitiveness scenery and the implementation of mechanisms that generates economic efficiency, finance sufficiency, social fairness, environmental adjustment and a balanced coverage of the provided services. This study suggests a methodology to appraise sustainable water rate in regards the covered socioeconomically classes, and its application was effectuated in the city of Natal- RN’s water supply system. It was identified that the average rate amount is R$ 3,67/m3 and, using cross subsidy, the calculus was made covering many social classes. The level of subsidy more appropriated to be used is 49,5% and, with this subsidy, the rate amount for E class, less socially fortunate, will be, considering the base year as 2007, R$1,85/m3. This rate projection shows that for A class costumers, more socially fortunate, the monthly average rate will be increased in 37%, and it will be R$ 5,03/m3. In accordance with the presented model, the rate structure will vary based on the costumer’s socio-economical conditions. By increasing the rates for the superior strata of society, is possible to obtain a lower rate for the less socially fortunate. The company’s income will be enough to cover the costs due to counterbalancing rates between all costumers’ groups. With the proposed rates, Natal’s water supply system will be totally economically and financially sustainable xviii with warranties of environmental preservation for the system area. In addition to this, it will bring more social fairness for costumers from less fortunate classes.