• Proceedings of the Korea Water Resources Association Conference
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• 한국수자원학회 2007년도 학술발표회 논문집
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• pp.1798-1802
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• 2007

The practice of business estimate flood discharge by rainfall-flow relation that is easy collection of observation data. The important factor is rainfall, coefficient of runoff, and drainage area for analysis of runoff-flow relation.The practice of business usually use probability rainfall that use a weighted average value after each observation post estimate probability of non-same time. It has more error than same time probability rainfall, and it can excess of estimation because it can't consider space distribution of rainfall.The study of result showed similar aspect with existing ARF but width of coefficient become smaller. And the comparison of peak flow did not different what used by ARF and same time probability rainfall(A group). But non-same time probability rainfall is bigger 25% more than another(B group). Between A group and B group of the difference increased with the lapse of time.

• Journal of Industrial Technology
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• 제27권A호
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• pp.95-102
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• 2007

The practice of business estimate flood discharge by rainfall-flow relation that is easy collection of observation data. The important factor is rainfall, coefficient of runoff, and drainage area for analysis of runoff-flow relation. The practice of business usually use probability rainfall that use a weighted average value after each observation post estimate probability of non-same time. It has more error than same time probability rainfall, and it can excess of estimation because it can't consider space distribution of rainfall. The study of result showed similar aspect with existing ARF but width of coefficient become smaller. And the comparison of peak flow did not different what used by ARF and same time probability rainfall(A group). But non-same time probability rainfall is bigger 25% more than another(B group). Between A group and B group of the difference increased with the lapse of time.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.783-786
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• 2008

The main goal of this study is to understand the effects of direct-runoff of chemistry and organic fertilizers which are adsorbing to sediment from farmland and non-point source discharge characteristics which are discharged to stream with soil erosion when rainfalls. pollutographs of TSS, BOD, COD, TN, and TP were measured for 10 rainfall events at watershed. EMC (Event Mean Concentration) were calculated for each rainfall event using quality and quantity measured. The result shows that the EMC ranges of 95% confidence intervals are 50.5-203 mg/L for TSS, 0.8-14.2 mg/L for $BOD_5$, 4.2-20.7 mg/L for $COD_{Mn}$, 0.2-0.5 mg/L for TP, 2.4-4.5 mg/L for TN, 1.36-3.04 mg/L for NO3--N, 0.13-0.42 mg/L for NH4+-N and 0.82-1.77 mg/L for TKN.

• Korean Journal of Soil Science and Fertilizer
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• 제44권6호
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• pp.1264-1271
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• 2011

To build environmentally friendly highways, we testes suitability for unique characteristics of pollution mitigation facility around the highways by evaluating optimal selections and implementation methodologies to minimize loan of non-point pollution substances into water-ways. To do this we categorized EIA target highways into three types ; big drainage basin, small drainage basin, and bridge section as to minimize non-point pollution of highway runoff. The terms of selected facility test based on the Natural and Manufactured Treatment Device were removal efficiency of TSS, BOD, COD, T-N, T-P, compatibility of site selection, economic feasibility, maintenance convenience, and the final mitigation facility.

• International conference on construction engineering and project management
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• The 7th International Conference on Construction Engineering and Project Management Summit Forum on Sustainable Construction and Management
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• pp.346-352
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• 2017

This study discusses application of the storm water management model (SWMM) to designing the sponge city facilities in the Athletes Village of Military World Games in Wuhan in October 2019. The SWMM was used to simulate the runoff processes and reduction efficiencies of the sponge city facilities. The runoffs of the sponge city facilities were compared with those of traditional drainage system for the design rainfall of 35.2mm and the rainfalls with different recurrence periods. The results show that the hign density sponge city facilities could meet the requirements for 80% of annual runoff control rate, SWMM can determine the scales of the sponge city facilities and effectively simulate the hydrological processes for different layout schemes. The simulation model is also helpful to making optimization of the sponge city facility layout.

• Journal of The Korean Society of Agricultural Engineers
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• 제57권2호
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• pp.75-83
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• 2015

This study was aimed to estimate the total application cost and utilization of Turf grass VFS application through the field experiment. The experimental plots were constructed in an upland field of Iksan city within the Saemangeum watershed. Turf grass was transplanted at the down-slope edge of the pollution source area in each of the treated plots. Three rainfall events were monitored during the experiment period, and the rainfall-runoff relationships and NPS pollution reduction effects of the VFS systems were assessed. As results, the reduction ratio of runoff volume ranged 14.1~64.0 %, while the NPS pollution reduction ratio ranged 9.8~73.9 % for SS, 24.0~84.2 % for T-N, 31.6~80.9 % for T-P respectively. The total cost of VFS application was estimated by considering purchase cost of Turf grass sods and construction and maintenance costs of VFS system as well as the loss caused by giving up crop cultivation for the area needed to construct the VFS. The total cost of the VFS was estimated to be approximately \3,379,000/ha/year for the first year of application, and this cost could be decreased to \1,899,000/ha/year from the second year as the construction cost of VFS could no longer need to be counted afterwards. Apart from the NPS pollution reduction effects, the possible utilization of VFS was examined by detaching Turf grass within 40 % of VFS area for sale during spring time when the VFS systems fully covered. The benefit of selling the detached Turf grass sods was estimated as \1,260,000/ha/year, and also found that the VFS area successfully recovered by the time of the summer period. This benefit could attract farmers to adopt the VFS technique to manage agricultural NPS pollution.

• Magazine of the Korean Society of Agricultural Engineers
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• 제44권5호
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• pp.116-126
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• 2002

Discharge pattern and water quality were investigated in the drainage water from about 10 ha of groundwater-irrigated paddy field in the growing season of 2001. Total discharge quantity was about 1,117.2 mm in which about 75% was caused by management drainage due to cultural practice of paddy rice farming and the rest by rainfall runoff where total rainfall was about 515 mm. Dry-day sampling data showed wide variations in constituent concentrations with average of 26.14 mg/L, 0.37 mg/L, 3.54 mg/L at the inlet, and 43.60 mg/L, 0.34 mg/L, 3.58 mg/L at the outlet for CO $D_{cr}$ , T-P, and T-N, respectively. Wet-day sampling data demonstrated that generally CO $D_{cr}$ followed the discharge pattern and T-P was in opposite to the discharge pattern, but T-N did not show apparent pattern to the discharge. Discharge and load are in strong relationship. And based on regression equation, pollutant loads from groundwater irrigation area are estimated to be 288.34, 1.17, and 5.45 kg/ha for CO $D_{cr}$ , T-P, and T-N, respectively, which was relatively lower than the literature value from surface water irrigation area which implies that groundwater irrigation area might use less irrigation water and result in less drainage water, Therefore, total pollutant load from paddies irrigation with groundwater could be significantly lower than that with surface water. This study shows that agricultural drainage water management needs a good care of drainage outlet as well as rainfall runoff. This study was based on limited monitoring data of one year, and further monitoring and successive analysis are recommended for more generalized conclusion.

• Journal of Wetlands Research
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• 제21권spc호
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• pp.98-106
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• 2019

The coefficient and exponent of the MUSLE(Modified Universal Soil Loss Equation) runoff factor in the SWAT(Soil and Water Assessment Tool) model are 11.8 and 0.56 respectively, which are equally applied to the estimation of soil erosion regardless of land use. they could derive overestimation or underestimation of soil erosion, which can cause problems in the selection of soil erosion-vulnerable area and evaluation of reduction management. However, there are no studies about the estimation of coefficients and exponent for the MUSLE runoff factor by land use and their applicability to the SWAT model. Thus, in order to predict soil erosion and sediment behavior accurately through SWAT model, it is necessary to estimate the coefficient and exponent of the MUSLE runoff factor by land use and evaluate its applicability. In this study, the coefficient and exponent of MUSLE runoff factor by land use were estimated for Gaa-cheon Watershed, and the differences in soil erosion and sediment from SWAT model were analyzed. The coefficient and exponent of runoff factor estimated by this study well reflected the characteristics of soil erosion in domestic highland watershed. Therefore, in order to apply the MUSLE which developed based on observed data of US agricultural basin to the domestic watershed, it is considered that a sufficient modification and supplementation process for the coefficient and exponent of the MUSLE runoff factor depending on land use is necessary. The results of this study can be used as a basic data for selecting soil erosion vulnerable area in the non-point source management areas and establishing and evaluating soil erosion reduction management.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2007년도 정기총회 및 학술발표대회
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• pp.595-598
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• 2007

Urban storm water collection and conveyance systems are critical components of the urban infrastructures. During a storm event, street grate inlets are usually loaded with debris by the first-flush runoff volume. Grate inlets are subject to clogging effects. Effective interception area of grate inlets was decreased by clogging. It also decreased the interception capacity of grate inlets and increased the inundation area in street. Therefore, it is necessary to analyze the clogging characteristics and interception capacity change by clogging for appropriate design and management of grate inlets. In this study, field survey was executed to investigate debris and clogging pattern of grate inlet in 9 areas. The clogging factor with consideration of urban area characteristics was estimated with the field survey results.

• Journal of Environmental Science International
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• 제11권7호
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• pp.621-626
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• 2002

Depth-area-duration(DAD) relations are important to hydrological plans and designs for the water resources as well as the flood defence. And these relations have been still in analysis and use today because they can be applied to readily available data. In this paper, rational and consistent DAD models were developed using the multiple regression analysis and basic relationships of area ratio-runoff volume about heavy rainfall occurring in the Im-Jin river basin, 1999. In addition, revised DAD models and curves that can convert a maximum point rainfall to mean area rainfall were developed and evaluated. As results, these models seem to have predictive value in order to plan and design hydrological structures of flood defence in the Im-Jin river basin.