• Journal of Korea Water Resources Association
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• v.44 no.4
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• pp.263-273
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• 2011

Recently increased rainfall by abnormal climate, risen peak runoff by urbanization, and shorten time of concentration are causing frequent overflow at downstream basin. This problem will be solved through the runoff reduction facilities like detention pond. However so far, most studies about detention pond in Korea are focused on its capacity. A study with respect to outlet facilities of detention pond was insignificant. Design of culvert usually used for outlet facilities of detention pond is generally carried out by using "Road Drainage Design" of Korea Expressway Corporation (1991). So detention pond is unreasonable to apply it. In this study, the culvert flow in submerged condition of upstream at culvert was analyzed., and simplified design procedure for culvert outlet facilities were presented for detention pond.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.5
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• pp.930-934
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• 2006

In this study, we conducted water-quality analysis of wastewater and in-situ flow measurement using automatic flow rate measuring instrument to identify characteristics of wastewater in urban areas, and collected samples in gutter fur storm water drain, rainfall bucket, and aqueduct of pipe from roof, and outfalls of basins to examine the contribution by pollution origins such as base wastewater, atmospheric washing, runoff by roof surface, runoff by road surface, erosion of sewer sediment. In the result, the concentration of pollutants reached peak in the beginning of rainfall due to first flush, was 3 to 10 times higher than average concentration of dry period, and was lower than that of dry period due to dilution of storm water. In the analysis of the contribution by pollution origins, the ratio of load by sewer sediment resuspension to the total pollution load was 54.6% fer COD, and 73.3% fur SS. Accordingly, we can reduce the total pollutant load by periodical dredging and washing of sewer sediment, and control the loadings by overflow of combined sewer overflows.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.3
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• pp.395-406
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• 2016

Population and development are concentrated by urbanization. Consequently, the usage of underground area and the riverside area have been increased. By increasing impermeable layer, the urban basin drainage is depending on level of sewer. Flood damage is occurred by shortage of sewer capacity and poor interior drainage at river stage. Many of researches about flood stress the unavailability of connection at the river stage with the internal inundation organically. In this study, flood calculated considering rainfall and combined inland-river. Also, using urban runoff model analyze the overflow of sewer. By using results of SWMM model, using flood inundation analysis model analyzed internal drainage efficiency of drainage system. Applying SWMM model, which results to flood inundation analysis model, analyzes internal drainage efficiency of drainage system under localized heavy rain in a basin of the city. The results of SWMM model show the smoothness of internal drainage can be impossible to achieve because of the influence of the river level and sewer overflow appearing. The main manholes were selected as the manhole of a lot of overflow volume. Overflow reduction scenarios were selected for expansion of sewer conduit and instruction retention pond. Overflow volume reduces to 45% and 33~64% by retention pond instruction and sewer conduit expansion. In addition, the results of simulating of flood inundation analysis model show the flood occurrence by road runoff moving along the road slope. Flooded area reduces to 19.6%, 60.5% in sewer conduit expansion scenarios.

• Journal of Korean Society on Water Environment
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• v.23 no.6
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• pp.945-950
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• 2007

The stormwater runoff from paved area are highly polluted because of particulate materials as well as metals from various vehicular activities. The Division of Road Maintenance in Ministry of Construction and Transportation was recently developed the Guidelines of Environment-kindly Road Maintenance. It is actually requiring the BMP construction to control the nonpoint source pollution as based on the TMDL program. This research is carried out in order to define the characteristics of stormwater runoff from the toll-gate of highways since 2006, which is actually one of the main pollutant sources of paved areas. This monitoring is the first phase work for establishing the treatment facilities in the toll-gates. The one of the main characteristics from toll-gate runoff is the first flush phenomenon containing lots of sediments and metal compounds at the beginning of a storm event. Usually it is used to determine the size of treatment facilities and to calculate the reduced pollutant mass in the facility. The research results shows that the mean EMC vaules for heavy metals are determined to $274.3{\mu}g/L$ for Cd, $1,273.4{\mu}g/L$ for Cr, $1,822.0{\mu}g/L$ for Cu, $6,504.9{\mu}g/L$ for Fe, $14,930.3{\mu}g/L$ for Pb, and $714.1{\mu}g/L$ for Zn. Also the metal mass loadings from the toll-gates are calculated using EMC, watershed area and storm duration.

• Journal of Korean Society on Water Environment
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• v.27 no.5
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• pp.605-616
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• 2011

The first flush phenomenon and the Mass First Flush (MFFn) were analyzed for various rainy events in trunk road. Applicability for estimate MFFn using SWMM was evaluated by comparision with observed MFFn. First flush phenomenon was investigated by normalized cumulated (NCL) curve of every pollutant based on ten times of rainfall events monitoring data from 2008 to 2009. As a result, magnitude of first flush phenomenon varied with the pollutants and rainfall events. First flush phenomenon was detected highly in the trunk road. MFFn was estimated by varying n-value from 10 to 90% on the rainfall events. The n-value increases, MFFn is closed to '1'. As time passed, the rainfall runoff was getting similar to ratio of pollutants accumulation. The result of a measure of the strength of the linear relationship between observed data and expected data under model was good ($R^2$=0.956). As the final outcome, we have good reliability, estimation and application of MFFn using model seem statistically possible.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.1
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• pp.104-110
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• 2006

Growth in population and urbanization has progressively increased the loadings of pollutants from non-point sources as well as point sources. Accordingly, release of contaminants from non-point sources, released with surface runoff of rainwater, is influenced by atmospheric phenomena, geology, and topography. This makes the control of non-point source difficult. Therefore, this study intends to reveal the characteristics of runoff and particle size distribution to observe the fundamental characteristics of runoff. Experiments were carried out at inner road of research center. Average concentration of runoff ranged from 26.8 to 126.4 mg/L for SS and $COD_{Cr}\;15.3{\sim}117.7mg/L,\;TN\;0.07{\sim}5.16mg/L,\;TP\;0.06{\sim}0.49mg/L$ and heavy metals $0.00{\sim}0.29mg/L$. First flush, indicated wash off of pollutant at first rain, was observed for all types of pollutants. Most pollutants revealed a very close correlation with SS ($R^2=0.93{\sim}0.99$). After analyzing characteristics of particle, particle was finer than that from previously examined data.

• Journal of Korea Water Resources Association
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• v.49 no.6
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• pp.537-549
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• 2016

The grate inlets generally were installed to intercept surface runoff on the roads and intercepted flow was drained to the underground sewer system. The equation of interception flow was used to determine the size and spacing of grate inlet on the roads. Therefore, it is necessary to analyze the interception capacity of grate inlet. Hydraulic experimental apparatus which can be changed with the longitudinal slopes(2, 4, 6, 8, 10%) of street, the transverse slopes(2, 4, 7, 10%), and the lengths(50, 100, 150cm) of grate inlet was installed for this study. The range of the experimental discharges were calculated with change of road lanes(2, 3, 4) and design frequencies(5, 10, 20, 30year). As the transverse slope increased, it led to the increase of interception capacity at grate inlets. The long lengths of grate inlet with direction of flow increased the interception capacity by the increase of side inflow. On the basis of the hydraulic model experiment results, the empirical equations for calculation of the interception capacity were derived with regression analysis. As a result of comparison with equations, the suggested equation of this study was estimated reasonable one for increased design frequency. Therefore, this study can suggest the basic data for design of drainage facility at road.

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.5
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• pp.59-64
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• 2008

The urban is possessing of various landuses such as commercial, industrial, residential and official areas. All of these landuses is including the paved areas that are roads and parking lots. The NPS (nonpoint sources) pollutants are generally originated from pavement areas in urban by human activities. Especially the roads are stormwater intensive landuses because of high vehicle activities and high imperviousness. The main NPS pollutants from roads are particulates and metals from vehicles and pavements. The Korea MOE (Ministry of Environment) is developing the NPS control program to reduce the NPS pollutants from the basins. However, it is not easy to control the NPS because it has high uncertainty by characteristics of rainfalls and watersheds. Therefore, this research was conducted on characterizing the runoff and providing mean EMC from roads. The monitoring were performed for total 16 rainfall events from a road in Youngin City since 2006. The results show that the TSS is highly correlated with other pollutant parameters. The statistical regression models using TSS EMC have been developed to easily determine the EMC of other pollutant parameters.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.19 no.5
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• pp.19-27
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• 2016

This study is to find appropriate plant for infiltration swale (which is natural LID infrastructure) and suggest basic research database for building infrastructure of LID facilities. Through the research inside, it first selects the plant strong to flooding and salt tolerance. Also, the research built infiltration swale along the road, planted those strong plants and monitored how well those plants adapted into the environment. Particularly, it showered 72mm/hr-speed artificial shower, also with natural shower, given that plants were vulnerable to flood because of influx of the rain. As a result of field applicability monitoring, Pennisetum alopecuroides and Equisetum hyemale (which degrade the pollutant well and adapt into rainy environment) are planting individually, or Juncus effusus var. decipiens, Liriope platyphylla, Miscanthus sinensis Andersson, Euonymus japonica (which are strong to rainy environment) and Pennisetum alopecuroides and Equisetum hyemale are mixed planting. The research should have monitored the plant for more than one year to study them, but the research only lasted five months. Therefore, it is hard to generalize. After all, through the long term research, it should pursue study more on appropriate plant materials and database that can be the reference for infrastructure establishment and maintenance.

• Journal of Korean Society of Forest Science
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• v.84 no.2
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• pp.239-246
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• 1995

This research aimed at the contribution to obtaining the scientifical data which were required for planning she environmentally sound and sustainable management, particularly in the field of the logging road construction. Main natural environmental variables including natural vegetation, rainfall, soil runoff were measured in the logging road on-sites and analysed. This project was carried out at the (mt.)Paekunsan Research sorest of Seoul National University, located in Gwangyang, Chollanam-do in southern part of Korea, from 1993 to 1994. 1. The explanatory variables for erosion and sedimentation on logging road surface were accumulated rainfall, erosion distance, cross-sectional gradient, and soil hardness. The erosion and sedimentation on logging road was increasing positively in proportion to the accumulated rainfall, soil distance from starting point of the logging road, and cross-sectional gradient. 2. On cut-slope of logging road, cut-slope shape, part of the slope, plant coverage, soil hardness, sand content, accumulated rainfall, clay content, and silt content were effective factors. Cut-slope erosion and sedimentation on logging roam increased as with the lower plant coverage, the lower accumulated rainfall, the high sand content in the soil. 3. On fill-slope of logging road, there were three significant variables such as total rainfall and number of rainfall-storm. Fill-slope erosion and sedimentation had a positive correlation with the amount of rainfall, the number of rainfall, the soil hardness. 4. The total erosion and sedimentation on logging road were $5.04{\times}10^{-2}m^2/m^2$ in logging road construction year, $7.37{\times}10^{-2}m^2/m^2$ in next year. The erosion and sedimentation on logging road surface were 32.7% of total erosion and sedimentation on Logging road in construction year, and 57.1% in next year, respectively. The erosion and sedimentation on cut-slopes were 30.4% on logging road in construction year, fill-slopes of total erosion and sedimentation and 21.0% in next year, respectively. The erosion and sedimentation on fill-slopes were 36.9% on logging road in construction year, 21.9 in next year. To decrease the erosion and sedimentation at the logging road from the beginning stage of construction, the effective revegetation works should be implemented on the cut-slope and fill slopes, and erosion control measures such as optima. road design must be constructed on read surface.