Aproveitamento de água pluvial em uma escola municipal na zona rural do município de Bagé - RS

Abstract

Water is one of the fundamental natural resources for any kind of life. And currently there are problems with the scarcity of this in several parts of the world, whether due to excessive consumption, pollution or lack of rain. For this reason, it is necessary to search for processes to reuse water or capture rainwater and reuse it, in processes that do not require drinking water. Currently, this water resource is treated as sewage and is wasted, but it has enormous potential to be used in schools, homes, shops and other places for non-potable purposes, thus making them sustainable places, with the advantage of saving the consumption of potable water. In addition, this way of saving water is a resource accessible to all, regardless of social class. Therefore, the present work aims to propose a system for capturing and using rainwater for non-potable purposes for a municipal school, located in the rural area of the city of Bagé - RS. The school receives 5000L of potable water weekly, totaling 20m³ per month and the proposed system provides for a 25% reduction in potable water consumption, generating savings of R$29.95 per month in the DAEB water tariff. The roof area where rainwater will be collected is 362 m2 . The necessary volume of the water tank that will store rainwater was dimensioned by the method of NBR 15527, reaching the value of 5 m3 . The Aquasave method was also used, which showed the feasibility of installing this system. As for the treatment of stored water, it is necessary to place chlorine tablets, inside a float, of the same type used in swimming pools, in the water tank and the replacement of the tablets must occur every 15 days. The investment value of the proposed system was R$ 4760.00 and the payback period is 159 months, that is, approximately 13 years. The installation of the system is feasible, even considering 13 years for the return on investment, since this value is small compared to the 50-year forecast of the durability of the installed system. Another factor that justifies the implementation of the system is the possibility of using rainwater and saving drinking water during the dry season that occurs in the city of Bagé.