PREDICTION OF SURFACE RUNOFF USING THE GREEN-AMPT INFILTRATION-MODEL AND ESTIMATED SOILS PARAMETERS

A modified form of the Green-Ampt infiltration equation was tested on a small agricultural watershed in western Quebec. Soil input parameters were obtained from nomographs currently available in the literature. An advantage of these nomographs is that they eliminate costly and tedious field measurements. However, these nomographs were not previously examined in Canada. Predicted and measured values of surface runoff were compared. Improved simulations were obtained when initial moisture conditions were taken into account. However, the nomographs require some modification before they can be used with confidence on Canadian soils.