Análise de variáveis determinantes no consumo urbano de água de uso doméstico na cidade de Campina Grande-PB.

Abstract

Within a world scenario of increasing urbanization, urban water demand management plays the role of a great challenge to be faced by water managers and public policy-makers. This makes it important to develop researches which support decision-making and allow urban water management measures to be effective, guaranteeing water rational use. At this context, this thesis utilized the multivariate statistical techniques Factor Analysis and Multiple Linear Regression Analysis in order to determine: (a) the participation level of socioeconomic and climatic variables in urban domestic consumers’ behavior; and (b) a water household consumption linear regression model that allows domestic consumption behavior to be foreseen in order to subsidize a better urban water network planning. The city of Campina Grande was selected as study case, due to the severe water supply crises it has faced along its history. Sixteen districts (32.65%) of the city were selected as a sample, based on their socioeconomic characteristics and spatial distribution at the city’s urban area (North, South, East and West zones, and four districts by zone). It was considered as: (a) socioeconomic variables: population by age group, family income, water tariff, and the number of economies supplied by the water supply company; and (b) climatic variables: maximum temperature, average of maximum temperatures, precipitation, evaporation (or evaporated volume), air relative humidity, average wind speed, and sunlight level; utilizing a 9-year monthly data series (2000-2008). The results show that: (a) the 0-49 age group is the one which exerts major influence on water household consumption, presenting a 103 l/inhabitant.day per capita consumption; (b) the climatic variables were not statistically significant at the adopted significance level (5%); the socioeconomic variables water tariff and family income were pointed out as determinant variables for the city’s water household consumption. Based on these results household consumption linear regression models were defined, by district and by zone. Along with economic instruments adoption, the estimation of water consumption reduction through water demand management measures adoption pointed out supply company’s (CAGEPA) investments for leakage reduction as the most effective water management measure in order to achieve water rational use at the city.