SUSTAINABLE WATER MANAGEMENT IN AN EDUCATIONAL INSTITUTION: RAINWATER HARVESTING POTENTIAL AT IFPA – CASTANHAL CAMPUS

Abstract

Rainwater harvesting in public buildings is an alternative for sustainable water resources management and for reducing potable water consumption in uses that do not require this quality. This study evaluated the water potential of rainfall incident on the roof of a three-story teaching building at the Federal Institute of Education, Science and Technology of Pará (IFPA) – Castanhal Campus. A roof area of 693 m², monthly precipitation data for 2021–2025 from the National Institute of Meteorology (INMET), 720 daily users, a reference consumption of 6 L/person/day, and 22 operating days per month were considered. The mean annual precipitation for the period, obtained from the sum of monthly averages, was 1,909.16 mm. Rainwater volume was estimated from precipitation and roof area. The results indicated an estimated annual gross volume of 1,323.05 m³ compared with an annual demand of 1,140.48 m³, corresponding to a volumetric supply/demand ratio of 116.0% and a positive theoretical annual balance of 182.57 m³. In the monthly analysis, surpluses were identified in February, March, April, May, and July, whereas the remaining months showed deficits. The results demonstrate the potential of the studied roof area to support the implementation of rainwater harvesting strategies for non-potable uses, contributing to sustainable water management practices in the institutional environment.