Assessment of Rainfall Runoff Based on the Field Measurements on an Embankment

When modeling soil/atmosphere interaction, it is of paramount importance to determine the rainfall runoff on a soil surface. Indeed, in the mass balance for bare soil, the rainfall transfers to runoff, infiltration, and evaporation. Knowing rainfall and runoff, the infiltration and evaporation terms can be determined, defining the hydraulic boundary conditions for soils. In practice, rainfall is measured through field measurements in weather stations; evaporation is often estimated using simple models, such as the Penman-Monteith model. Infiltration can then be calculated if runoff is known. However, estimating runoff is often a difficult task in practice. In this study, a runoff measurement method was developed using a collector system set up on a slope of an embankment with lime/cement treated silt. The runoff measurements were compared with the recorded rainfall, and a satisfactory agreement was obtained, showing the performance of the developed runoff measurement approach. A correlation between runoff and rainfall was thus proposed based on the hourly runoff and rainfall data. This correlation can be further used to estimate the rainfall runoff for similar embankments.