The development of models of hydrologic systems requires the description of individual processes in mathematical terms and the solution of sets of complex equations in differential form. This project is focused on developing mathematical descriptions of flow and water-quality processes that can be linked together to form such models. Research is needed on application of mathematical theory to the modeling of transport of sediments, including mudflows and hyperconcentrations such as occur after natural disasters such as volcanic eruptions or dam failures. This project is focused on developing mathematial description of flow and water-quality processes that can be linked together to form models of hydrologic systems and developing mathematical techniques for efficient solution of equations on digital computer techniques for studying sensitivity of parameters. For current information about work being done by this project, including investigations into hydrologic and erosional responses of burned watersheds, see project's home page.