In many parts of Canada and around the world, pressure on water resources, both in terms of water quality and quantity, from urban areas, agriculture, and industry are increasing, resulting in significant challenges in sustainable water resources management. In addition, in many regions of the world climate change will increase the frequency of extreme events (e.g., droughts and floods), which will have significant impacts on, among other things, our ecosystems, water resources, urban areas, and agricultural and food systems, which in turn will have ramifications on water and food security. The capacity of communities to mitigate against, and adapt to, such complex problems is presently constrained by many factors, including: i) a lack of water resources data in many watersheds that can help support water resources modeling and management; ii) challenges in providing highly accurate forecasts of non-linear and non-stationary water resources variables, and providing uncertainty assessments for decision makers; and iii) a lack of meaningful participation of key stakeholders in water resources modeling and management, coupled with our limited knowledge and modeling ability of the complex coupling of physical and social-economic activities in water resources systems. To directly address these three critical issues, this research program will follow a three pronged approach to develop, test, and implement: i) Methods to improve water resources data records for modeling and management. This will involve new approaches to extend water resources records in short-gauged sites, as well as estimate water resources records in ungauged sites. ii) Methods to improve short term water resources forecasting. This will involve new approaches to address non-linearity, non-stationarity, and uncertainty assessment in water resources forecasting. iii) Methods to improve the incorporation of key stakeholders and social aspects in water resources modeling and management. This will involve a new participatory social-physical systems modeling approach to represent and couple interactions between physical and social-economic processes that govern water resources systems. This research program will facilitate the transition towards more sustainable water resources management, and will provide training of highly qualified personnel in a unique combination of state-of-the-art concepts and approaches in the fields of hydrology and integrated, collaborative, and adaptive water resources management.