Environmental Revitalization of the River Basins of the Guapiaçu and Macacu Rivers to Increase Water Security in the Eastern Region of Guanabara Bay, Rio de Janeiro-RJ

Purpose: Evaluate the implementation of interventions with environmental sustainability in the Guapiaçu and Macacu river basins, in Rio de Janeiro, based on the concept of nature-based solutions, for the regulation of river flows. Theoretical reference: Principles that assess the water retention of rainwater through infiltration in slopes and plains of valley bottoms in the basin, in order to mitigate volumes of surface runoff, and increase artificial recharge of the aquifer. Method: The methodology presents data on the characterization of the Guapiaçu and Macacu basins, as well as information regarding the collection of hydrological data, specifically related to streamflow measurement in both basins. Results and conclusion: The results indicate periods of flow rates above average, corresponding to annual river discharges, with flood flows reaching over 120 m3/s in the Guapiaçu River and 220 m3/s in the Macacu River, with high availability of rainfall runoff in the region. Research implications: Proposed interventions for environmental sustainability in the Guapiaçu and Macacu river basins, with a forecast of increasing the minimum flow rates of the Guapiaçu and Macacu rivers to meet the expansion of water supply for the Baía de Guanabara region. Originality/value: The proposal for revitalizing basins through unconventional and nature-based solutions has less impact and presents originality, as it ensures the sustainability of water resources with water security in water supply associated with lower cost.