• Journal of Korean Society on Water Environment
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• v.37 no.2
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• pp.103-113
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• 2021

In this study, an Excel-based model (ROADMOD) was developed to estimate pollutant loading from the road and evaluate BMPs. ROADMOD employs the Chezy-Manning equation and empirical expression for estimating surface runoff, and power function for pollutant buildup, and exponential function for pollutant washoff in SWMM. The results of model calibration for buildup and washoff using observed data revealed a good match between the simulation results and the observed data. The long-term surface runoff and sediment simulated by ROADMOD demonstrated a good match with those by SWMM with 2 ~ 14% of relative error. The shorter sweeping interval (within 8 days) remarkably decreased sediment loads from the road. It was found that the effect of reducing sediment loads from the road was greatly affected not only by the sweeping interval but also by sweeping on the day before a rainfall event. The 48% of removal efficiency of sediment loads from the road was achieved with 26 times of road sweeping per year when sweeping was performed on the day before the rainfall event. A 4-day sweeping interval showed similar removal efficiency (48%) with 96 times of sweeping per year. It is considered that the road sweeping on the day before a rainfall event could maximize the effect of reducing the non-point source pollution from the road with minimization of the number of road sweeping. So, the road sweeping on the day before a rainfall event can be considered as one of the useful and best management practices (BMPs) on road.

• Journal of Korean Society on Water Environment
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• v.20 no.6
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• pp.555-562
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• 2004

This paper presents the development and application of a riparian buffer zone design model(RBZDM). The model was developed as a decision-making tool for watershed management, by integrating geographic information system(GIS) and analytical hierarchy process(AHP) theory. Several factors for watershed management, such as pollution removal capacity, land aquisition cost, distribution of point and non-point pollution sources, and possibility of new pollution source location, were analyzed based on AHP theory. The vegetated buffer zone width was designed using GIS-based riparian buffer analysis. The developed model was applied to the Kyoungan Stream watershed, which is an important part of Paldang lake catchment area. The Kyoungan stream watershed was divided into sixteen subbasins. Six of them belong to the main stem, where the model was applied. Ten alternatives of buffer zone width and five hierarchial levels were designed. The relative importance and the relative preference were computed by pair-wise comparison of evaluation criteria given in hierarchial levels. The buffer zone width was determined by linear function of the given alternatives and relative preferences. From this study, it was determined that the six buffer zone widths of Kyoungan main stems would be 1,594, 1,744, 1,856, 1,782, 1,338, 1,780 meter, from upstream to downstream.

• Journal of The Korean Society of Agricultural Engineers
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• v.64 no.3
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• pp.33-43
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• 2022

South Korea's agricultural nitrogen balance and phosphorus balance rank first and second, respectively, among OECD countries, and proper nutrient management is required to preserve the water quality of rivers and lakes. This study evaluates the effects of furrow mulching on the reduction of non-point source pollution (NPS) load from a sloped upland. The study site was Wanju-gun, Jeollabuk-do, and the survey period was from 2018 to 2019. The slope of the testbed was 13%, and the soil type was sandy loam. The cropping system consisted of maize-autumn Chinese cabbage rotation. The testbed was composed of bare soil (bare), control (Cont.), furrow vegetation mulching (FVM), and furrow nonwoven fabric mulching (FFM) plots. Runoff was collected for each rainfall event with a 1/100 sampler, and the NPS load was calculated by measuring the concentrations of SS, T-N, and T-P. The NPS load was then analyzed for the entire monitoring and crop cultivation periods. During the monitoring period, the effect of reducing the NPS load was 1.5%~44.5% for FVM and 13.1%~55.2% for FFM. During the crop cultivation period, it was 1.2%~80.5% for FVM and 27.0%~65.1% for FFM, indicating that FFM was more effective than FVM. As the NPS load was fairly high during the crop conversion period, an appropriate management method needs to be implemented during this period.

• Journal of Wetlands Research
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• v.15 no.3
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• pp.387-396
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• 2013

Non-point pollution source is difficult to control due to uncertain outflow path and emission. So, There are many development and research to Best Management Practices(BMP) established to manage the Non-point pollution source. Besides, various methods of estimated efficiency to exact assessment of BMP is presented. In this study, the impact about length of Grassed Swale on reduction efficiency based on monitoring results of Grassed Swale by length is studied. By estimating Grassed Swale reduction efficiency in a variety of methods, the difference between the methods of estimated efficiency was compared with those that. Estimated efficiency method using ER, SOL, ROL, ROF, SOLF, and ROLF methods is analyzed. EMC analysis result is high inflow and outflow concentration distinction organic compound for nutritive salts The result of efficiency analysis along Grassed Swale length sharply increases in a Grassed Swale inlet. After this increase, the efficiency gradually decreases. This is expected that cistern installed in the end of the front. To obtain a stable reduction efficiency of Grassed Swale, minimum length 30m of Grassed Swale should be enough. Also, in order to efficiently and economically design Grassed Swale, the researches on length of Grassed Swale are needed rather than simple analysis of efficiency.

• Journal of Environmental Impact Assessment
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• v.18 no.5
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• pp.281-291
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• 2009

In Total Water Pollutant Load Management System of Korea, unit load approach based on land register data is currently used for the estimation of non-point pollutant load. However, a problem raised that land register data could not always reflect the actual land surface coverages which determine runoff characteristics of non-point pollution sources. As a way to overcome this, we tried to establish quantitative relationships between the aerial images (0.4m resolution) which reflect actual land surface coverages and the land registration maps according to the 19 major designated land-use categories in Kyeongan watershed. Analyses showed different relationships according to the land-use categories. Only a few land-use categories including forestry, road and river showed essentially identical and some categories such as orchard, parking lot and sport utility site showed no relationships at all between image data and land register data. Except for the two cases, all the other categories showed statistically significant linear relationships between image data and land register data. The analyses indicate that using high resolution aerial maps is a better way to estimate non-point pollutant load. If the aerial maps are not available, application of the linear relationships as conversion factors of land register data to image data could be an possible option to estimate non-point pollutant loads for the specific land-use categories in Kyeongan watershed.

• Journal of Korean Society on Water Environment
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• v.30 no.1
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• pp.87-94
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• 2014

According to the technical guideline of water pollutant load management, the rainfall captured ratio which can be estimated by the empirical formula is an important element to estimate reduction loads of non-point pollutants water quality control basin. In this study, the rainfall captured ratio is altered to stormwater captured ratio considering its meaning in the technical guideline of water pollutant load management, and the new empircal formula of stormwater captured ratio is suggested. In order to do this, we calculate stormwater captured ratio by using the hourly rainfall data of seven urban weather stations (Busan, Daegu, Daejeon, Gangreung, Seoul, Gwangju, and Jeju) for 43 years. The regression coefficients of the existed empirical formula cannot reflect the catchment properties at all, because they are fixed values regardless of regions. However the empirical formula of stormwater captured ratio has flexible regression coefficients by runoff coefficient(C), so it is allowed to consider the characteristics of runoff in catchment. It is expected that reduction loads of storage based water quality control basin can be more reasonably estimated than before.

• Journal of Korean Society on Water Environment
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• v.36 no.1
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• pp.29-35
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• 2020

To manage the non-point source pollution and restore the water circulation, many technologies including infiltration or reservoir systems were installed in the urban area. These facilities have many problems regarding maintenance as their operation period becomes lengthier. The purpose of this study was to estimate the optimal maintenance timing through a long-term load test on the infiltration trench as one of the low impact development techniques. An infiltration trench was installed in the demonstration test facility, and stormwater was manufactured by Manual on installation and operation of non-point pollution management facilities from the Ministry of Environment, Korea and entered into the infiltration trench. Particle size distribution (PSD), suspended solids (SS) removal efficiency, and infiltration rate change tests were performed on inflow and outflow water. In case of the PSD, the maximum particulate size in the outflow decreased from 64 ㎛ to 33 ㎛ as the operating duration elapsed. The SS removal efficiency improved from 97 % to 99 %. The infiltration rate changed from 0.113 L/sec to 0.015 L/sec during the operation duration. The maintenance timing was determined based on the stormwater runoff requirements with these changes in water quality and infiltration rate. The methodologies in this study could be used to estimate the timing of maintenance of other low impact development techniques.

• Journal of Korean Society on Water Environment
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• v.39 no.4
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• pp.343-355
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• 2023

After the implementation of the total pollution load control system, the effect of improving river water quality by expanding investments in basic environmental facilities, inducing operational efficiency, and reducing the load of various pollutants was clear. However, since the implementation of the system, the management of non-point pollutants has been neglected; management focused on specific substances (biochemical oxygen demand (BOD) and total phosphorus (T-P)) and lacked specific cause analysis and action plans, failed to establish a relationship between water quality and pollution load, failed to reflect stakeholder demands for river water quality management, and failed to apply technical conditions. Therefore, to overcome the limitations raised and achieve a practical and efficient advanced total pollution system, the current system was partially improved and will continue to be improved. This study analyzed the performance and limitations of the total pollution system and introduced recent improvements and the contents that are being improved. The main contents included reducing emissions and reduction monitoring, using water quality tele-monitoring system (TMS) data and self-measurement data, adding population-inducing facilities, and adjusting regional development projects from 20 to 30 multi-family housing units, currentizing each pollutant source according to the roadmap. If the system is improved in a developmental direction and responds to various changes, it will be a more practical and effective policy.

• KCID journal
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• v.21 no.1
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• pp.99-108
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• 2014

This study investigated the effects of NPS(non point source) pollution reduction of sediment traps through field experiments. Various sizes of 4 sediment traps were applied in a upland field located in Gunwi and assessed the infiltration and storage effects as well as NPS pollution reduction effects of this technique. The characteristics of deposited soil in the sediment traps were also analyzed including distribution of particle size, soil texture, and chemical properties. The results showed that slightly different composition of soil particle size from each sediment trap with high proportion of 0.15mm and 0.25mm ranges of soil particle diameters, while the loamy sand is the main types of deposited soils in the sediment traps. Decreased NPS pollution were observed from the water quality analysis of the samples taken from the sediment traps. Further research need to be proceeded continuously to improve this technique in order to utilize on upland fields for management of agricultural NPS pollutions.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.16 no.2
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• pp.41-52
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• 2013

Anyang Stream Restoration Movement was started from 2001 for the construction of ecological city. The facilities for reuse of treated sewerage have been used since 2003 for improvement of water quality, maintenance of water quantity, river ecological restoration, and hydrophilic space. Thus, the Anyang city has been gradually transformed to eco-friendly city after the construction of Anyang stream and Hakui stream as natural rivers. In this study, biological and chemical methods as well as ecological indicators for Anyang mainstream and major tributaries were monitored for four years in between 2008 and 2012. The water quality and the diversity of species in most of the streams were found to be good except Anyang main stream. It appears that the influence of seasonal drying stream is almost disappeared except Sammak stream. Thus, the values for BOD (Biochemical Oxygen Demand) and BIP (Biological Index of Pollution) for Anyang main stream were found to be 5.27~3.42mg/l and 4.51~5.50, respectively. This is considered to be caused by the reused water quality of treated wastewater being exceeded the design criteria or by the non-point source of contaminants around the stream. However, entire section of tributaries shows I, II grade as a good water quality.