Impact of rainfall and soil hydraulic property information on runoff predictions at the hillslope scale

The stochastic‐conceptual model designed by Freeze (1980) to investigate rainfall‐runoff processes on a hillslope was modified to examine the impact of hydrologic data in simulating rainfall‐runoff events. Analysis of almost 12,000 synthesized rainfall‐runoff events generally shows that the spatial description of soil hydraulic properties has a greater impact on the characterization of hillslope runoff than corresponding descriptions of rainfall. Estimates of peak storm flow and time to peak were found to be less accurate than estimates of storm flow depth for the same level of information illustrating that different levels of information may be required to make predictions of equal efficiency for different summary variables.