• Journal of Korea Water Resources Association
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• v.47 no.1
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• pp.1-10
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• 2014

This study aimed to analyze water cycle at Taehwa river, Dongcheon, Hoiya river and Cheongryang cheon in Ulsan city using CAT model developed by Korea Institute of construction technology. To apply CAT model, we separated Teahwa river into 25, Dongcheon into 11, Hoiya river into 17 and Cheongryangcheon into 5 subbasins and discriminated between contribution runoff basins and source basins. The results of water cycle analysis performed using rainfall datas measured from 1975 and 2008 and hydrologic datas of change of land use etc. were that surface runoff increase and interflow decrease, caused by the increase of impervious area. The increases of surface runoff at the basin of Taehwa river and Dongcheon which is a tributary of Taehwa river were small and similar to each other respectively as 1.7% and 2.4%, and increased high rate of 3.2% and 7.7% in Hoiya river and Cheongryangcheon including subbasins which are having high rate of urbanization.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.2
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• pp.507-519
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• 2013

This study is to evaluate agricultural water supply capacity in Geum river basin (9,865 $km^2$), one of the 5 big river basin of South Korea using MODSIM-DSS (MODified SIMyld-Decision Support System) model. The model is a generalized river basin decision support system and network flow model developed at Colorado State University designed specifically to meet the growing demands and pressures on river basin management. The model was established by dividing the basin into 14 subbasins and the irrigation facilities viz. agricultural reservoirs, pumping stations, diversions, culverts and groundwater wells were grouped and networked within each subbasin and networked between subbasins including municipal and industrial water supplies. To prepare the inflows to agricultural reservoirs and multipurpose dams, the Soil and Water Assessment Tool (SWAT) was calibrated using 6 years (2005-2010) observed dam inflow and storage data. By MODSIM run for 8 years from 2004 to 2011, the agricultural water shortage had occurred during the drought years of 2006, 2008, and 2009. The agricultural water shortage could be calculated as 282 $10^6m^3$, 286 $10^6m^3$, and 329 $10^6m^3$ respectively.