• Journal of environmental and Sanitary engineering
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• v.14 no.3
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• pp.1-9
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• 1999

In the estimation of pollution load in water basin, a data information has generally used from surveyed data. A Geographic Information System(GIS) was adopted to evaluate the amount of pollution load in Anyang stream basin which is one of the major tributaries in the Han river flows through urban area. The digital maps of administrative boundary, stream network, sub-basin, soil type, and land-use for spatial data as well as attribute data were generated. And the database of sub-basins and pollution source was structured to estimate pollution load in Anyang stream basin by an Arc/Info GIS.As the results of this investigation, the pollution load of Mokgam-chun sub-basin was the highest amount. And that of Hagi-chun sub-basin and the fourth main stream sub-basin were also high amount in Anyang stream basin. In general, it was found that the pollution load generated from the upstream area in Kyunggi province was higher than that from downstream area in Seoul. Because the point and non-point source pollution load played very significant role in the deterioration of the water quality of the Anyang stream, an integrated approach to water quality management should be required for the sub-basins of high pollution load amount.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.4
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• pp.859-866
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• 1994

It is difficult to make an exact estimate of the peak discharge or the runoff depth of flood and establish the proper measure for the flood protection since the water stage or discharge has been nearly measured at most medium or small river basins. The objective of this study is to estimate parameters of the discrete, linear, input-output model for medium or small river basin. The On-Cheon River basin in Pusan was selected for the study area. The runoff data used in the study has been observed since June 1993, and the effective rainfall was determined using the storage function method. The parameter sets of the discrete, linear, input-output model were estimated using the least squares method and the correlation function method, respectively. The calculated hydrographs by the discrete, linear, input-output model regenerated the observed outflow hydrographs well, and also the simulated flood hydrograph was comparable to the observed one. Therefore, it is believed that the discrete, linear, input-output model is simpler than other runoff analysis methods, and can be applied to a medium or small river basin.

• Journal of the Korean GEO-environmental Society
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• v.7 no.4
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• pp.43-52
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• 2006

There were huge damages of human beings and their properties in many areas of the basin of the Nak-Dong river by the unusual weather and the localized downpour recently. In this research against disasters, we want to know strength of the cemented sand that is mixed with cement and poor-graded sand, to estimate CSG(Cemented Sand and Gravel) method used coffer dam in Japan, which is the materials of riverbed in the basin of the Nak-Dong river for levee's construction. For that, we want to provide the fundamental data which need in the examination of adaptation of levee's material, design and analysis by investigating compressive strength by curing period and cement content, elastic modulus and stress by transformation from compaction test, CBR test, unconfined compression test and triaxial compression test as changing cement content from 2% to 8% at two sites in the basin of the Nak-Dong river.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.1182-1186
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• 2006

The decision of design flood in river basins is very important in the aspect of flood control. The design flood of rivers was estimated according to the size and importance of basins. As the damage of floods increases more and more and the importance of defense against floods increases further, the presumption of design flood can be very important. Especially, what influences most greatly flood is rainfall. However, in spite of equal rainfall, the estimated flood differ according to the features of basins. The fact that the features of basins influence greatly the estimation of flood was confirmed by the preceding research results and experiences. However, although many rivers have their own basin features, the research on how these basin features are related to the estimation of design flood, is not yet sufficient. The purpose of this study is to identify how the design flood estimated previously by river arrangement basic plan is correlated with topography factors, and so investigate the correlation between basin topography factors and design flood in order to provide the additional information for the unmeasured basins or the middle/small river basins where their river plan is not established.

• Journal of Korea Water Resources Association
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• v.33 no.5
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• pp.623-634
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• 2000

This study describes results of numerical simulations on river flow response due to global warming. Forecasts of changes in climatic conditions are required to estimate the hydrologic effects of increasing trace gas concentrations in the atmosphere. However, reliable forecasts of regional climate change are unavailable. In there absence, various approaches to the development of scenarios of future climatic conditions are used. The approach in this study is to prescribe climatic changes for a river basin in a simplified manner. As a rule, such scenarios specify air temperature increases from $0^{\circ}C\;to\;4.0^{\circ}C$ and precipitation change (increase or decrease) in the range of 0% to 15%. On the basis of acceptable supposition of warming scenarios. future daily streamflow is simulated using rainfall-runoff model in the Andong Dam basin. The numerical experiments have quantitatively revealed the change of discharge at 2010, 2020, 2030 and 2050 for each warming scenarios and compared it with the results for a non-warmmg scenano.cenano.

• Journal of Environmental Science International
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• v.29 no.8
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• pp.857-870
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• 2020

In this study, the antibiotic components in the final effluent from the 12 wastewater treatment facilities located in the Nakdong River basin were investigated, and the correlation between organic matters, nutrients and antibiotics was analyzed. In the final effluent of the wastewater treatment facilities, three sulfonamides antibiotics (sulfamethazine, sulfathiazole, sulfachlorpyridazine) and tetracyclines antibiotics (oxytetracycline, doxycycline) were detected. Sulfamethazine were detected at all points and ranged from 10.398 to 278.784 ng/L. Sulfathiazole were detected at 6 points (Andong, Gumi, Hapcheon, Miryang, Uiryeong, Haman), and ranged from 23.773 to 144.468 ng/L. The correlation coefficients between sulfathiazole and TSS, COD, TOC, NH₃-N, NO₂-N, and T-N components were high in the range of 0.73 to 0.92. The correlation coefficient between sulfamethazine and T-N was 0.48, and the correlation with the rest of the water quality components was low. The correlation coefficient between sulfamethazine and sulfathiazole was 0.78. Through this study, it was confirmed that the concentration of sulfonamides antibiotics was higher than the concentration of tetracyclines antibiotics in the final effluent of 12 wastewater treatment facilities in the Nakdong River basin, and the concentration of sulfathiazole increased with organic matters and nutrients.

• Journal of Korea Water Resources Association
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• v.38 no.2
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• pp.111-119
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• 2005

The climatological characteristics of the area averaged monthly precipitation over the Han- and Nakdong-river basins were investigated. The data used for this study is monthly precipitation data from 51 meteorological stations for the period of 1954 to 2002. The magnitude of area averaged precipitation in the Han-river basin was about 10% larger than that in the Nakdong-river basin. However, the variability of two monthly precipitation time series exhibited similar characteristics: April precipitation tends to decrease and August precipitation increase significantly, while there was no significant trend for the other months. There were some indications of abrupt change around the 1970's in the periodicity of precipitation and relationship with El Nino index. September precipitation showed negative correlation with NINO3 index but November precipitation, positive correlation with NINO3 index, indicating a possible connection with the global-scale phenomena.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.9
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• pp.830-839
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• 2010

This study presents a constituent load estimating procedure that can be operated with the present Korean TMDL monitoring system. The modified TANK model is used as a daily river flow simulation model whose parameters are estimated from 8-day intervals flow data. Constituent loads are estimated with the 7-parameter log linear model whose parameters are estimated by the minimum variance unbiased estimator. Results from Nakdong river basin reveals that the proposed procedure provides satisfactory TOC and BOD load estimates. As an application, a representative load duration curve is derived for working out a way to represent the overall hydrologic flux of BOD, COD and TOC at Nakdong river basin. The present water quality can be checked stochastically by Load Duration Curve through this study and presented visually.

• Journal of Korean Society for Geospatial Information Science
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• v.12 no.1 s.28
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• pp.39-44
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• 2004

The SCS-CN method was known to have difficulties to the applied to the mountainous area like Korean river basins. This study focused to develop a distributed SCS-CN method considering river basin slopes from GIS data. For the purpose, the method was applied to Sulma river and compared with area weighted average method and distributed SCS-CN method using GIS. According to the results, SCS-CN method considering river basin slopes provided better effects on the estimating effective rainfall on the other methods. The necessity of the generalization of the results to the other rivers was discussed.

• Journal of The Korean Society of Agricultural Engineers
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• v.62 no.6
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• pp.97-109
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• 2020

The objective of this study was to assess spatial variation of the target water quality criteria and excess rate in Nakdong river basin after the Total Maximum Daily Loads (TMDLs). For this, 41 total water quality monitoring stations were selected BOD and T-P data were collected from 2003 to 2019. The annual average water quality of BOD and T-P were calculated and compared with the target water quality for each stations by peroid. As a result of analyzing the BOD, Kumho A, Nakbon F, Namgang D, Miryang B, Wicheon B and Hoecheon A exceeded the target water quality criteria for two consecutive times. For T-P, Nakbon N, Naeseung B, Miryang A, Hwanggang A and Hoecheon A exceeded the target water quality criteria twice in a row. In the case of T-P, the target water quality excess rate was relatively low after the TMDLs implementation compared to before the TMDLs implementation. However, in the case of BOD, there was no difference in the target water quality excess rate before and after TMDLs. As a result, the overall annual average water quality shows a decreasing trend, but it is necessary to manage the water quality for the Nakdong river basin that exceed the target water quality.