The three 104(g) opportunities this cycle are focused on the following topics:

• General 104(g): Water problems and issues of a regional or interstate nature beyond those of concern only to a single state – “Successful research topics have included research on improving and enhancing the nation’s water supply, developing innovative approaches to water treatment, evaluation of the dynamics of extreme hydrological events and associated costs; development of methods for better estimation of the physical and economic supply of water; developing approaches for integrated management of ground and surface waters; and the evaluation and assessment of conservation practices.” (G23AS00485)
• Per-and Polyfluoroalkyl substances (PFAS) research: Understanding the impact of PFAS on water resources. “Successful research topics have included research on the fate, persistence, transport, and impacts of Per-and Polyfluoroalkyl (PFAS) substances on changes to water quality and/or ecosystem dynamics, in water resources, including surface water and groundwater.” (G23AS00484)
• Aquatic Invasive Species (AIS) research: Understanding the impact of aquatic invasive species on water quality and quantity in the Upper Mississippi Basin. “Successful research topics have included research on improving our understanding of the impacts of aquatic invasive species on lakes and rivers in the Upper Mississippi River basin, including changes to water quantity, quality and ecosystem dynamics and the social and/or economic assessment of the spread, detection, impacts, solutions, and management of aquatic invasive species in the Upper Mississippi River basin.” (G23AS00483)