Análise de investimento em aproveitamento de água de chuva: estudo de caso para um condomínio residencial em Feira de Santana – BA

Abstract

The lack of water, its misuse by consumers and the high value of the same when treated makes the people look for alternatives to the consumption of water. One possibility is to use rain water for non-potable uses. The rain water capitation reduces costs for the consumer due to the non-purchase of water by the concessionaire that explores the water supply services. Also, mitigates the effects of floods, increasingly common in large cities due to the advancement of impermeable areas resulting from the increase in buildings, such as road works, buildings, removal of vegetation aspects that contribute to decreasing soil infiltration capacity. The cost of implementing the system is relatively low, since the major cost component is the tank. To scale it, it is considered the area catchment, the rainfall data in the region and the required demand. This study therefore aims to determine whether the implementation of this system is viable in a residential condominium located in Feira de Santana - BA, using rainwater captured in the common area of the condominium in toilet flushing, garden watering and waterproof area washing. By applying the methods of Liquid Present Value and Analysis of Benefit / Cost, the results achieved attest be economic viability of the project with return on investment in 4 years and 2 months, demonstrating that it’s not necessary needing to purchase 210 m3 / year of water potable to the condo.