Surface water flow in landscape models: 2. Patuxent watershed case study

We developed a system for modeling regional, spatially explicit hydrology in a way that allows integration with broader plant, nutrient, and socio-economic model components. The relatively coarse spatial and temporal resolution of these broader components relative to existing hydrologic models requires a different approach to hydrologic modeling. We developed a quasi-empirical model which still retains as much of the underlying process dynamics as possible. We tested the approach in the Patuxent watershed, Maryland, USA where we needed a time step of 1 day (compared to 1 h in most hydrologic models) and a spatial resolution of 1 km2. The model was developed, calibrated and tested at several spatial and temporal scales and extensive testing shows that it performs at least as well as more complex hydrologic models, even using the 1 day and 1 km2 resolution.