Avaliação de um sistema de aproveitamento da água da chuva em edificação residencial – estudo de caso na cidade de Alegrete – RS

Abstract

This work was developed in order to evaluate the technical and economic viability in terms of the utilization system of rainwater installed in a residential multifamily building in the city of Alegrete, RS. The work is justified by evaluating a highly relevant alternative in the engineering field for water conservation in a place where consumption is high and where almost half of the total water consumed is designed for non-potable purposes. In carrying out this research, we made the characterization of the study area, checking the design of capture and use of existing stormwater facilities, analysis of the economic efficiency of the system and improvement proposals and / or new structures suggestions to the use system. As a result, it found that the facilities have a percentage of comprehensive care for non-potable demand of only 29%, with failure in 71% of simulated days. This low attendance rate is associated with small catchment area used to collection system. The use of rainwater recovery installations generates a negligible monthly savings in financial terms, approximately R $ 41.73 per month, which makes time return on investment of approximately 27 years, relatively high payback time for possession of the premises and the profile of the building. However, the adoption of some improvements in the system design, such as increasing the catchment area and its increased storage volume, increase by more than five times the generated financial savings. Thus, it is possible to infer that the existing system in the building of study does not have great economic viability with the structures currently installed, however, the inclusion of some improvements in the system design would make the system extremely advantageous. Technical and environmental terms, the building system has essentially viable, considerably reducing the consumption of drinking water and showing itself as an efficient way to contribute to the reduction of shortages currently experienced.