Evaluación de la factibilidad de cosechar agua lluvia en la ciudad de Cuenca, como método de gestión ambiental para ahorrar agua potable

Abstract

Cuenca is characterized by having a good system of drinking water supply. The geography of the area and the good management practices of the water utility allow the service to be affordable and easily accessible. However, the drinking water supply is threatened by the high demand per capita; therefore, it has been estimated that a shortage of this resource will happen by the year 2050. Therefore, it is necessary to propose alternatives that allow the optimization of the resource. In this way, this research evaluates rainwater storage or harvesting system, on the roofs of houses in the city of Cuenca through daily analysis of rainwater storage, based on: rainfall in the city; the catchment area, run-off losses, the effectiveness of the system, the demand for rainwater in the home, and the size of the storage tank. The evaluation of the rainwater harvesting system was based on different indices that make it easier for the user to make decisions according to their requirements and circumstances. Different scenarios of catchment and use of rainwater were generated, considering the realities of households. Results show that rainwater harvesting can reduce the consumption of potable water up to an 18.45 %, in those activities that do not require the use of it, such as flushing in toilets and cleaning the home, in addition to the associated financial savings. Additionally, the rainwater harvesting is presented as an environmental management strategy, because this activity would prolong the life time that the hydrological sources of the city are able to supply the inhabitants.