Run off Coefficient on Quaternary Volcanic Landform of Citarik Catchment based on Rainfall-Discharge Measurements, West-Java, Indonesia

Upper Citarum Catchment where the Capital City of West Java Province, Bandung, Indonesia located in that area is very popular as Bandung Basin or as Bandung Plato. Citarik, one of the main river tributaries of Upper Citarum River has a similar environmental or hydrological problem as that of Upper Citarum, i. e. , flood in rainy and drought in dry season. The study area, Citarik Upper Catchment of Young and Old Undifferentiated Volcanic material (lava, breccia, and tuff) of denudational hilly landform has an area of about 2880 Ha and five order river based on Strahler Stream Ordering System. Runoff coefficient was calculated using rainfall and river discharge data based on direct field measurements. Topographic Map with scale of 1 to 25000 was also analyzed using GIS techniques to describe volcanic landform characteristic quantitatively. The research aims to obtain runoff coefficient of the Quaternary Volcanic Denudational landform. The study result was that runoff coefficient in young volcanic product is higher than in old volcanic product. Vegetation cover is still have importance role in determining run off coefficient, although there is also found indication that geological factor have.