Nonpoint source pollutants primarily originate from agricultural areas, settlements, and contaminated lands. Soil erosion and deposition are the means of transportation of pollutants since soil particles not only absorb but also transport contaminants through the stream network. Nature-based solutions (NbSs) are quite popular around the world to mitigate soil erosion and deposition, which has accelerated due to climate change and other anthropogenic activities. To promote their adoption, we developed an online decision support system (DSS) to provide land and water managers and particularly stakeholders with the optimal NbSs and ecosystem-based approaches (EbAs) that could help protect watersheds, streams, and consequently seas from pollutants. This DSS incorporates a descriptive data management system to handle datasets (questions, answers/criteria, outputs/solutions) from various stakeholders (e.g., policymakers, urban planners, environmentalists) and other non-experts. The questions of the DSS are related to different characteristics (criteria) of the areas of interest for the NbS or EbA. The questions provide various answers (which serve as descriptive data) in order to weigh the criteria/characteristics and, ultimately, the proposed NbS. The NbSs of the DSS were recorded based on a bibliographic review and from stakeholders’ responses via forums, meetings, workshops, etc. The primary testing results by stakeholders showed that the online DSS has the potential to be used as a complementary service in the near future. Specifically, it can provide the optimal NbS based on the participants’ answers about the study area. This communication paper may act as an invitation to reach a greater audience of stakeholders for the improvement of the online DSS.