Biophysical Benefits Simulation Modeling Framework for Investments in Nature-Based Solutions in São Paulo, Brazil Water Supply System

In order to understand the hydrological impacts of nature-based solutions in Cantareira Water Supply System, this study evaluates six different land cover and use change scenarios. The first second consider restoration native vegetation riparian areas, third prioritizes sites using biophysical characteristics (optimized scenario derived from Resource Investment Optimization System—RIOS), fourth considers best management practices fifth sixth are hypothetical extreme scenarios converting all pasture forest vice versa. Two models were developed represent distributions water yields watershed: HEC-HMS SWAT. Simulation results indicate that when implemented, surface runoff is reduced ambient storage increases during rainy season (December–March); while overall flow dry (June–September). combination specific hydrologic components RIOS-customized intervention simulation outputs—namely flows groundwater contribution stream flows—indicate on average 33% increase yield, or 206 hm3/year, across watershed comparing against baseline conditions. same modeling scenario, sub-watersheds adjacent reservoirs showed an 58% (or 341 hm3/year). adopting NbS source can mitigate drought conditions contribute toward building long-term security.