Nature-based Solutions for Wastewater Treatment (NbS-WT) is becoming increasingly popular since it not only uses less energy to treat wastewater but also improves urban greenery, which is beneficial to economic and social development. The use of NbS-WT has been pushed internationally to achieve sustainable urban city development and respond to climate change. In Vietnam, uncontrolled urbanization is worsening canal pollution, resulting in a decline in the quality of life and the esthetic of the cityscape. This work examined the current status of urban canal wastewater and the applicability of NbS-WT using waste stabilization ponds (waste stabilization ponds (WSPs), centralized system) and floating treatment wetlands (Floating treatment wetlands (FTWs), decentralized system). The WSPs, such as maturation ponds, can be used to create more urban green space, biodiversity, centralized wastewater treatment, flood control, urban heat control, and fish farming practices. Additionally, FTWs aided in the development of the canal landscape, provided employment opportunities for those working in the maintenance, and encouraged the participation of many stakeholders. The lessons learned from the study could be used not only to upgrade the next generation of WSPs and FTWs but also to give public decision makers with recommendations for scaling up NbS-WT processes for sustainable urban city development.