STEADY-STATE ANALYSIS OF INFILTRATION AND OVERLAND FLOW FOR SPATIALLY-VARIED HILLSLOPES1

ABSTRACT: An envelope of steady-state surface runoff response for a hilislope is established in terms of the probability distribution and spatial arrangement of individual point infiltration capacities and the rainfall intensity. Minimum overland flow is shown to occur when point infiltration capacities are ordered with the highest at the slope bottom, while maximum overland flow occurs when the highest point capacities are at the top of the slope. Equations for envelope curves are developed for both continuous distributions and discretely sampled data; examples for each case are given. Use of the analysis as a rainfall-runoff model is also discussed.