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There is an increasing need for improved process-based decision support tools for watershed management. Many of the tools available to assist managers in locating and selecting effective management practices are either too general or too complex to be used practically. Empirical models based on historic data may not be relevant to future climates. In this study, we present a simple web-based Hydrologic Characterization Tool (HCT) that can be used to analyze the effects of management practices on the hydrology, erosion, and sediment delivery within specific landscapes. The HCT, based fundamentally on the Water Erosion Prediction Project model, was developed as a simple tool to help managers build a process-based understanding of the hydrologic flow paths and the processes driving erosion for common management practices within a region. Users select a range of soil characteristics, slope attributes, and crop rotations common for their region and then select management options which are currently being applied in the region or are being considered as potential future conservation options. The HCT then creates input files for all possible combinations of attributes and provides annual and monthly hydrologic and soil erosion output for both within and at the outlet of each hillslope. The output allows users to not only compare the effect of the management practices for a single attribute, for example a reduction in soil erosion, but it provides them with an understanding of the effect of the practices on the hydrologic flow paths generating and delivering the pollutant through the hillslope. We illustrate characterizations from two regions of the US: Idaho and Iowa. Each of these locations has a unique set of climatic, topographic, and soil characteristics resulting in much different dominant hydrologic flow paths. We demonstrate that adoption of conservation/mulch tillage practices in Idaho effectively converts the dominant runoff generating process from an infiltration excess to saturation excess mechanism leading to a reduction in erosion. Understanding the interaction between soil depth and topography is critical for identifying saturation-excess processes. In contrast, since the rainfall intensities in Iowa are much greater than in Idaho, conservation tillage practices alone are not as effective at reducing erosion in Iowa as in Idaho. Managers in Iowa often must use terracing practices along with conservation tillage to successfully reduce erosion rates to acceptable levels. In addition to sediment transport we demonstrate how the HCT can be used to identify sensitive areas for soluble pollutants. Future versions of the tool will provide direct prediction of transport of nitrate, phosphorus, and pesticides within each landscape.