• 한국물환경학회지
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• 제26권4호
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• pp.598-607
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• 2010

One of constraints in the application of unit-load method to estimate non-point pollution loads in the total water pollutant load management system (TWPLMS) is the limited numbers of applicable unit-loads. Since only 7 unit-loads are currently available for total 28 land-use categories in the national land register data, each unit-loads inevitably have to represent several land-use categories regardless of their actual land coverage characteristics. As a way to minimize the problem, this study suggested a nested application of the available unit-loads based on the analysis of high resolution aerial images taken in the Kyeongan watershed. Statistical analysis of three selected land-use categories such as school, apartment complex, and golf course showed that there exit significant (95% confidence level) relationships between the registered land-uses and actual land coverages. The school and apartment complex currently considered as 100% ground have only 65% and 80% of ground characteristics, respectively. Golf course, which is considered as 100% pasture, has about 5% of ground area. This indicates that the unit-load method using in TWPLMS can give over estimated non-point pollutant loads for the school and apartment complex (19.8~54.4%) but under estimation for the golf course (80.9%).

• 한국물환경학회지
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• 제25권1호
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• pp.58-68
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• 2009

Low impact development (LID) technique is relatively new concept to reduce surface runoff and pollutant loading from land cover by attempting to match predevelopment condition with various integrated management practices (IMPs). In this study, computational model for designing and evaluating LID, named LIDMOD, was developed based on SCS-CN method and applied at Andong bus terminal to evaluate LID applicapability and design retention/detention area for volume or peak flow control. LIDMOD simulated with 21 years simulation period that yearly surface runoff by post-development without LID was significantly higher than that with LID showing about 2.8 times and LID could reduce efficiently yearly surface runoff with 75% reduction of increased runoff by conventional post development. LIDMOD designed detention area for volume/peak flow control with 20.2% of total area by hybrid design. LID can also efficiently reduce pollutant load from land cover. Pollutant loads from post-development without LID was much higher than those from pre-development with showing 37 times for BOD, 2 times for TN, and 9 times for TP. Pollutant loads from post-development with LID represented about 57% of those without LID. Increasing groundwater recharge reducing cooling and heating fee, creating green refuge at building area can be considered as additional benefits of LID. At the point of reducing runoff and pollutant load, LID might be important technique for Korean TMDL and LIDMOD can be useful tool to calculate unit load for the case of LID application.

• 상하수도학회지
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• 제29권5호
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• pp.551-557
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• 2015

The TMDL (Total Maximum Daily Load) has been used to determine the water quality target. LDC (Load Duration Curve) based on hydrology has been used to support water quality assessments and development of TMDL. Also FDC (Flow Duration Curve) analysis can be used as a general indicator of hydrologic condition. The LDC is developed by multiplying FDC with the numeric water quality target of the factor for the pollutant of concern. Therefore, this study was to create LDC using the stream flow data and numeric water quality target of BOD and T-P in order to evaluate the pollutant load characterization by flow conditions in Heukcheon stream. When it is to be a high-flows condition, BOD and T-P are necessary to manage. BOD and T-P did not satisfy the numeric water quality target for both seasons (spring and summer). In order to meet the numeric water quality target in Heukcheon stream, management of non point source pollutant is much more important than that of point source pollutant control.

• 한국지반환경공학회 논문집
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• 제7권6호
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• pp.57-65
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• 2006

본 연구에서는 호소 및 저수지의 수질을 예측하는데 널리 사용되는 WASP6 모델을 이용하여 저수지 수질을 예측함으로써 수질관리자의 수질관리 정책 및 의사결정에 효과적으로 반영하고자 하였다. 연구결과 오염부하량중 관광객에 의한 오염 배출부하량이 전체의 T-N, T-P 중 91.66%, 92.75%로 축산과 토지이용에 의한 배출부하량 보다 월등히 높은 것을 알 수 있으며, 이는 대상유역의 주 오염원이 관광객과 인구에 의한 것을 알 수 있다. 년도별 오염 배출부하량 예측결과 BOD는 2012년 현재 보다 약 1.6배, T-N은 2012년 1.5배 정도 T-P는 1.5배 정도 증가 할 것으로 예측되어, 오염부하량 저감을 위한 대책 마련이 시급한 것으로 판단된다. 수옥정 저수지의 BOD의 경우 현재 비교적 양호한 수질을 나타내고 있으나, 년도가 지날수록 수질오염이 증가할 것으로 판단되므로 시급한 오염저감시설 확충 및 관리가 필요하다. 특히 T-N과 T-P는 호소 부영양화 조절을 위한 제한 영양소임을 고려할 때 오염원 통제에 대한 집중적인 관리가 필요할 것이다.

• 한국환경과학회지
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• 제21권10호
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• pp.1235-1244
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• 2012

The objective of this study is to evaluate Flow-Pollutant load delivery ratio equations developed from rural watershed on main subwatersheds within Juam Lake. Two regression equations for BOD and three equations for T-P were evaluated on Bosung cheon, Dongbok cheon, Songgwang cheon, Naenam cheon, and Sinpyeon cheon. The results show that estimation of BOD delivery ratio using flow-delivery equation is reliable when relative composition of discharge load of pollutant sources of a watershed is similar to those of watershed where the equation developed. On the other hand, application of regression equation for T-P was feasible when the landuse pattern and relative composition of discharge load of pollutant sources of a watershed is similar to those of watershed where the equation developed.

• 한국습지학회지
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• 제6권3호
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• pp.47-54
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• 2004

본 연구에서는 수리 수문학적인 이론을 근거로 수질모델링을 위한 유달 오염부하량 산정방법을 제안하고자 한다. 본 연구에서 제안하는 방법은 격자기반으로 구성되어 있으며, 최대 경사 방향으로 일어나는 지표면 유출을 추적함으로써 유달부하량을 계산하게 된다. 또한 GIS 및 DEM 자료를 이용함으로써 공간적으로 분포된 배출 오염부하량, 지형, 경사, 토양특성, 토지이용 등을 고려할 수 있다. 이를 통하여 수질에 영향을 미치는 다양한 토지이용방법 및 유역관리방식의 대안에 대한 평가가 가능할 것으로 기대된다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2018년도 학술발표회
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• pp.448-448
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• 2018

In this study, the regression models (Load ESTimator and eight-parameter model) were evaluated to estimate instantaneous pollutant loads under various criteria and optimization methods. As shown in the results, LOADEST commonly used in interpolating pollutant loads could not necessarily provide the best results with the automatic selected regression model. It is inferred that the various regression models in LOADEST need to be considered to find the best solution based on the characteristics of watersheds applied. The recently developed eight-parameter model integrated with Genetic Algorithm (GA) and Gradient Descent Method (GDM) were also compared with LOADEST indicating that the eight-parameter model performed better than LOADEST, but it showed different behaviors in calibration and validation. The eight-parameter model with GDM could reproduce the nitrogen loads properly outside of calibration period (validation). Furthermore, the accuracy and precision of model estimations were evaluated using various criteria (e.g., $R^2$ and gradient and constant of linear regression line). The results showed higher precisions with the $R^2$ values closed to 1.0 in LOADEST and better accuracy with the constants (in linear regression line) closed to 0.0 in the eight-parameter model with GDM. In hence, based on these finding we recommend that users need to evaluate the regression models under various criteria and calibration methods to provide the more accurate and precise results for pollutant load estimations.

• 한국수자원학회논문집
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• 제31권1호
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• pp.35-44
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• 1998

본연구의 목적은 강우시 지표수의 흐름을 통해 유출되는 오염부하 산정 시스템을 개발하고 정상류 흐름의 성격을 띠는 점원오염의 월별, 수기별 오염부하를 산정하기 위한 각종 수질 인자별 발생부하와 배출부하 사이의 관계를 규명하여 각 지천 소유역의 울별 및 수기별 오염부하를 산정하는 모형 시스템을 개발하는 것이다. 또한 댐 상류 하천 구간에 대한 수질 모델링을 통하여 댐유입부의 오염부하를 산정하는데 있다. 대상유역의 토지 이용분포와 지표수 유출거동에 관련된 지상인자들의 파악을 위해 인공위성 원격탐사 이미지를 분석하여 토지이용분포 규명하고, 기타 지형공간정보를 구축하여, 이들로부터 모형의 운영에 필수적인 지상인자들을 합성하여, 모형의 입력자료로 사용될 수 있도록 하는 일련의 과정을 체계화하였다. 또한 개발된 개개의 모형을 체계적으로 결합하여 사용을 쉽게하기 위하여, GIS-모형간의 인터페이스 모듈과 그래픽 출력시스템 등 응용소프트웨어를 개발하여, 운격탐사 기법에 의한 저수지 오염 부하량 산정 모형과 전체시스템의 통합을 완료하였다. 개발된 모형시스템을 이용하여 1991년에서 1993년 사이에 관측된 4개 호우사상에 대한 비점오염원의 부하를 시험적으로 산정하였으며, 충추댐의 월별 및 수기에 따른 오염부하도 아울러 산정하였다.

• 한국물환경학회지
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• 제30권4호
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• pp.418-428
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• 2014

The purpose of this study is to predict the spatio-temporal changes in land uses and to evaluate land-based pollutant loads in the future under Total Water Pollution Load Management System using CLUE-S model. For these ends, sensitive parameters of conversion elasticities in CLUE-S model were calibrated and these calibrated parameters of conversion elasticities, level II land cover map of year 2009, and 7 driving factors of land use changes were used in predicting future land uses in 2002 with two scenarios(Scenario 1: non area restriction, Scenario 2: area restriction). This projected land use map of 2020 was used to estimate land-based pollutant loads. It was expected that urban areas will increase in 2020 from both scenarios 1 and 2. In Scenario 1, urban areas are expected to increase within greenbelt areas and deforest would be expected. Under Scenario 2, these phenomena were not expected. Also the results of estimation of BOD and TP pollutant loads, the BOD difference between scenarios 1 and 2 was 719 kg/day in urban areas and TP difference was 17.60 kg/day in urban areas. As shown in this study, it was found that the CLUE-S model can be useful in future pollutant load estimations because of its capability of projecting future land uses considering various socio-economic driving factors and area-restriction factors, compared with conventionally used land use prediction model.

• 한국농공학회논문집
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• 제61권3호
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• pp.15-22
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• 2019

In order to preserve water environment, Total Maximum Daily Load(TMDL) is used to manage the total amount of pollutant from various sources, and the annual average load of source is calculated by the unit load method. Determination of the unit load requires reliable data accumulation and analysis based on a reasonable estimation method. In this study, we propose a revised unit load estimation method by analyzing the unit load calculation procedure of National Institute of Environment Research(NIER) method. Both methods were tested using observed runoff ratio and water quality data of rice paddy fields. The estimated values with the respective NIER and revised NIER methods were highly correlated each other. However, the Event Mean Concentration(EMC) and the runoff ratio considered in the NIER method appeared to be influenced by rainfall classes, and the difference in unit load increases as the runoff and EMC increase. The error can be further increased when the EMC and runoff ratio are changed according to changes in rainfall patterns by climate change and change of agricultural activities. Therefore, it is recommended to calculate unit load by applying the revised NIER method reflecting the non point pollution runoff characteristics for different rainfall classes.