This study assesses the effectiveness of Sustainable Urban Drainage Systems (SuDS) in mitigating urban flooding and enhancing stormwater management in Machala, Ecuador. The implementation of SuDS resulted in a 57.64% reduction in flood volume and a decrease in peak flow from 10.50 m ³s ^-1 to 5.91 m ³s ^-1. Infiltration capacity improved from 0.75 mm to 2.43 mm, while average surface runoff was nearly halved from 19.27 mm to 10.48 mm. A specially designed porous concrete with approximately 30% porosity showed optimal performance. These findings indicate that SuDS can significantly contribute to urban planning and flood management in coastal developing cities. The study recommends prioritizing rain gardens and porous pavements, creating local SuDS guidelines, integrating these systems into urban planning, establishing long-term monitoring, and involving local communities. The insights gained here offer valuable guidance for other coastal cities in Ecuador and similar regions, demonstrating a sustainable approach to managing urban flooding and enhancing water resilience.