Mrrssw/Model of Rainfall-Runoff in Small Sub-Watershed

Abstract

A hydrologic model called MRRSSW (or KAHYAM in Turkish) was developed to simulate surface runoff of small watershed, which small earth dams may be built on its creeks to store storm water during rainy season and make this water available in dry season. The model computes monthly surface runoff rates employing daily rainfall data. Curve number method of Soil Conservation Service (1972) is used to simulate surface runoff amounts whereas the Blaney and Criddle equation (1950) is used to calculate evapotranspiration. The developed model was tested in 2 small watersheds, namely, Kirklareli-Vize and Istanbul-Catalca-Damlica creeks. Comparison of the simulated surface runoff values with the long-term directly measured data revealed that the model simulated the runoff precisely in the months with relatively smaller surface runoff. However, it slightly over-predicted the runoff amounts in November and December when relatively higher runoff rates occurred. It was concluded that the model can be safely applied in similar small sub-basins to simulate rainfall-runoff relationship with an acceptable deviation.