Surface water hydrology is particularly important in semi-arid and arid environments. Researchers within the Division of Hydrologic Sciences (DHS) study many aspects of surface water in all environments, but especially in the western United States. Using a multidisciplinary approach, both scientists and engineers perform basic and applied studies to better understand numerous hydrologic processes of surface water, such as alluvial fan hydraulics, rainfall-runoff response, flood and volume-frequency relationships in ephemeral streams, water quality in streams and watersheds, sediment and contaminant transport, and impacts on aquatic ecosystems. These comprehensive studies will provide better tools for various hydrologic research and management issues including streamflow forecasting, stream corridor restoration, predicting the effects of wildfire on surface runoff and erosion, stormwater management, and understanding impacts of changing land use activities on quality and quantity of hydrologic systems in the growing western US under changing climate conditions. Surface water researchers use both field monitoring, with state-of-the-art field measurement and laboratory techniques, and integrated modeling, requiring parameter estimation and optimization, in their studies. Collaboration with other DHS researchers studying vadose zone hydrology, hydrogeology, and ecological systems aids in studying the coupled processes between these systems. Many surface water researchers also teach and advise graduate students within the Nevada System of Higher Education universities.