Análise das séries de distribuição e consumo de água em Santa Maria – RS utilizando a metodologia de Box & Jenkins

Abstract

Among the natural resources, water is the most important element for the species’ survival. With the population growth, the demand for water increases. This, allied to the waste and the pollution of the water springs, generates a problem of great proportions: for how much time will water be available in nature. It is necessary to develop technologies that allow us a better planning for the use of water resources, investing in public policies of environmental education and awareness to the water issue. In this context, this work presents an analysis of the Distribution Series and Water Consumption in the city of Santa Maria – RS, in the period from January 2000 to December 2005, using Box and Jenkins Methodology, aiming to make forecasts twelve steps ahead. The data was collected by Companhia Riograndense de Saneamento – CORSAN. The series analysis showed that both have data homogeneity and pointed the SARIMA(1,1,2)(1,0,0)12 as the best model for the distribution series and SARIMA(1,1,2)(0,0,1)12 for the consumption series. Comparing the predicted values with the real ones, it was concluded that the two series presented variations. It is due to the fact that in the year of 2006, there was a significant decrease in the water volume of the Dam of DNOS, one of the city’s of water supply. Considering this, CORSAN made a differentiated planning for this year in order to avoid extended water rationing, and disruptions to the population.