Runoff Studies in a Small Catchment

Abstract

This paper discusses results from a field study in a small East-Norwegian catchment. The main object of the study was to separate the different runoff processes in a small catchment. Direct measurements of precipitation snowmelt, runoff and the saturated basin area were undertaken in the field together with chemical hydrograph separation. A functional relation between saturated area and runoff was established showing that the initial runoff being a good moisture indicator for a basin. Further the hydrograph of pure saturated overlandflow (produced from rain on the saturated area) may be separated from the rest of the runoff at any moment of time. This paper also discusses the results in view of existing methods to estimate soil moisture and to forecast runoff. One of the main conclusions is that the dynamic response area should be taken into consideration both in field investigations and in hydrological models, – specially in humid climate.