This project is aimed at identifying critical areas, providing practical solutions and mitigation strategies for coastal water quality and flood risk assessment in line with the increasing climate-change risk in the coastal catchment areas of the region (South-West Finland). By utilizing advanced, high-resolution and locally adaptable computational models, and coastal water quality monitoring data, the project will identify critical areas (hot spots) of pollutant discharges in the region and further estimate how and by which routes these pollutants enter the Archipelago Sea. There is an urgent need for this kind of information especially for the areas of island municipalities as the current regional runoff and water quality models, including WSFS-VEMALA, do not cover these areas. This necessitates novel and updated accessible solutions for climate-change adaptation and planning of flooding and load mitigation strategies in the region. Through advanced and refined computational models and affordable monitoring solutions, the project seeks to provide new data-driven knowledge on the current and future hydrological and water quality conditions in the Archipelago Sea coastal areas. The work will provide a base to assess possible impacts of extreme weather conditions of coastal runoff in unmonitored areas. Flooding, runoff, and pollutant loads are expected to increase due to climate change. Further, based on the data-driven assessment, the project will provide actionable solutions as well as guidelines for municipalities and concerned stakeholders in implementing effective, nature-based solutions, restoration, or land management practices to mitigate loading and enhance their resilience to flooding and water quality degradation.