• 한국물환경학회지
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• 제26권6호
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• pp.903-909
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• 2010

The purpose of this study was evaluated on the applicability of Load Duration Curve Method (LDC Method) using HSPF watershed model and sampling data for efficient TMDLs in Korea. The LDC Method was used for assessment pollutant characteristics in watershed and water quality variation in each water flow level. Load Duration Curve is applied for judge the level of impaired water-body and can be estimated the impaired level by pollutant, such as BOD, T-N, and T-P in this study depending on variation of stream flow. As a result, BOD, T-P was usually exceed the standard value at low flow and dry hydrologic period. Improvement of effluent concentration from WWTP and riparian buffer protection zone are effective to improve the water quality. T-N showed the worst condition at mid-range hydrologic period and moist hydrologic period. Therefore, soil erosion control program and BMPs for non-point source pollution control is effective for recovery the water quality, which can be useful method for management of water quality in the plan of recovery water quality spontaneously. Applicability of LDC Method was evaluated in the Nakbon A watershed. However, we need to consider more detailed and accumulated data set such as accurate GIS data and detail pollution data, and WWTP discharge water quality data for accurate evaluation of watershed. Overall, The LDC Method is adequate for evaluation of watersheds characteristics, and its application is recommended for watershed management and TMDL Implementation.

• 한국수자원학회논문집
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• 제41권1호
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• pp.101-113
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• 2008

본 연구는 안양천 유역의 물순환 건전화를 위한 최종 대안을 제시하기 위해 비용효과분석을 수행하였다. 이중 편익산정은 진술선호기법 중 하나인 실험선택법(Choice Experiments, CE)과 대안의 평가지수(Alternative Evaluation Index, AEI)를 결합하여 수행하였다. 실험선택법은 지역별로 다양한 속성을 보이는 안양천 유역을 잠재적 위험도와 지리적 특성을 바탕으로 6개 지역으로 나누어 설문과 분석을 수행하였다. NB > 0 이상인 대안들은 공학적, 경제적으로 매우 우수한 대안이므로 실행을 적극 검토할 필요가 있다.

• 한국물환경학회지
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• 제32권4호
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• pp.349-356
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• 2016

Total Maximum Daily Loads (TMDLs) System has been used to improve water quality in the Youngsan·Tamjin river basin since 2004. The Basic Policy of TMDLs sets up the standard flow based on the average dry condition or mid-range flow during the last 10 years. However, Target Water Quality (TWQ) assessment on TMDLs has been used to evaluate water quality through eight-day intervals over 36 times a year. The results for allocation evaluation and target water quality evaluation were different from each other in the same unit watershed during the first period. In order to improve the evaluation method, researchers applied Load Duration Curve (LDC) to evaluate water quality in nine unit watersheds of the Youngsan·Tamjin river basin. The results showed that achievement rates of TWQ assessment with the current method and LDC were 67~100% and 78~100%, respectively. Approximately 11% of the achievement rates with use of LDC were higher than those with use of the current method. In conclusion, it is necessary to review the application of the LDC method in all Four Major River Watersheds.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2003년도 학술발표논문집
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• pp.307-310
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• 2003

The purpose of this study was to obtain optimal amount of groundwater development for a rural small watershed. The optimal amount of groundwater development in this experimental watershed is 13.8 %($0.67{\times}10^6m^3$) of the annual rainfall by SCS-CN method. The Visual MODFLOW analyses showed the optimal amount of groundwater development were 14.9 %($0.72{\times}10^6m^3$) of the annual rainfall.

• 한국물환경학회지
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• 제32권5호
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• pp.450-457
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• 2016

The Total Maximum Daily Load (TMDL) is a watershed management system that involves the establishment of the target water quality, the calculation of permission loading (allocation loading), and the control of total pollutants for each unit watershed. Allocation loading is assessed through the comprehensive implementation assessment of the previous year's plan. Assessment results are used for follow-up management measures such as the limit of development and updating of TMDL Management Implementation Plans for the next planning period. Although detailed assessment criteria are important, they are not currently available. Therefore, we suggested assessment criteria by comparing two methods('integration method' and 'separation method') using combination point and non-point discharge loading. We also examined the penalty criteria considering controllable load local government and updating methods of the TMDL Management Implementation Plan for the next planning period.

• 대한원격탐사학회지
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• 제24권1호
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• pp.35-43
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• 2008

The purpose of this study is to evaluate the hydrological impact due to temporal land cover change by gradual urbanization of upstream watershed of Pyeongtaek gauging station of Anseong-cheon. WMS HEC-1 was adopted, and OEM with 200 m resolution and hydrologic soil group from 1:50,000 scale soil map were prepared. Land covers of 1986, 1990, 1994 and 1999 Landsat TM images were classified by maximum likelihood method. The watershed showed a trend that forest & paddy areas decreased and urban/residential area gradually increased during the four selected years. The model was calibrated at 2 locations (Pyeonglaek and Gongdo) by comparing observed with simulated discharge results for 5 summer storm events from 1998 to 2001. The watershed average CN values varied from 61.7 to 62.3 for the 4 selected years. To identify the impact of streamflow by temporal area change of a target land use, a simple evaluation method that the CN values of areas except the target land use are unified as one representative CN value was suggested. By applying the method, watershed average CN value was affected in the order of paddy, forest and urban/residential, respectively.

• 환경영향평가
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• 제22권5호
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• pp.439-454
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• 2013

UN-REDD (United Nations programme on Reducing Emissions from Deforestation and forest Degradation) is currently being emerged as one of important mechanism to reduce carbon dioxide in relation to the deforestation. Although administrative boundary has already gained world-wide recognition as a typical method of monitoring unit in the process of GHG (Greenhouse Gas) reduction project, this approach did not provide a realistic evidence in the carbon sequestering monitoring in terms of UN-REDD; the meaningful comparison of land use patterns among watershed boundaries, interpretation for distribution trends of carbon density, calculation of opportunity cost, leakage management, etc. This research proposes a comparative evaluation framework in a more objective and quantitative way for carbon sequestering monitoring between administrative and watershed boundary approaches. Mt. Geumgang of North Korea was selected as a survey objective and an exhaustive and realistic comparison of carbon sequestration between the two approaches was conducted, based on change detection using TM satellite images. It was possible for drainage boundary approach to identify more detailed area-wide patterns of carbon distribution than traditional administrative one, such as estimations of state and trends, including historical trends, of land use / land cover and carbon density in the Mt. Geumgang. The distinctive changing trends in terms of carbon sequestration were specifically identified over the watershed boundary from 4.0% to 34.8% while less than 1% difference was observed in the administrative boundaries, which were resulting in almost 21-22%. It is anticipated that this research output could be used as a valuable reference to support more scientific and objective decision-making in introducing watershed boundary as carbon sequestering monitoring unit.

• 한국물환경학회지
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• 제24권6호
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• pp.676-681
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• 2008

The evaluation of the effluent water quality of sewage treatment plant is one of the most important factor in calculating total maximum daily loads (TMDLs). Current method to calculate 95% upper limit of effluent water quality of sewage treatment plant assuming normal distribution of data needs to be implemented in case of non-normal distribution. We have investigated the applicability of percentile ranking method as a non-parametric statistical analysis in case of non-normal distribution of data.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2018년도 학술발표회
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• pp.106-106
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• 2018

Ecosystem service valuation is a crucial step for the sustainable management of watershed. In the context of various ecosystem services provided by watershed, this study, particularly deals with water yield computation in Bagmati Basin of Nepal. The water availability per population in Bagmati Basin is lowest compared to other basins in Nepal. Also, the rate of urbanization is rapidly growing over a decade. In this regard, the objectives of this study are 1) to compute the total water yield of the basin along with computation on a sub-watershed scale, and 2) Study the impacts of land use change on water yield based on CLUE-S model. For the study, Integrated Valuation of Environmental Services and Tradeoffs (InVEST), a popular model for ecosystem service assessment based on Budyko hydrological method is used to compute water yield. As well, CLUE-S model is used to study land use change, which is further related to study variation on water yield. The sub-watershed wise outcome of the study is expected to provide the guidelines for the effective and economic management of a watershed on a regional scale.

• 한국습지학회지
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• 제20권4호
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• pp.370-382
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• 2018

본 연구는 유역별로 홍수 피해에 영향을 미치는 항목을 정량적이고 효과적으로 평가하는데 목표를 두었다. 수자원장기종합계획(MOCT, 2001)에서는 홍수 취약성을 나타내는 홍수피해잠재능(Potential Flood Damage, PFD)을 개발하였지만 단순한 그룹화에 그치고 있으며 각 항목에 대한 세밀한 평가를 바탕으로 치수 계획에 대한 지침을 제시하지 못하고 있다. 이에 본 연구에서는 한강 유역에 대상으로 수자원장기종합계획에서 적용한 방법(기존 방법)과 실제 홍수위험지역 및 자료에 기반한 개선(안)에 따른 홍수피해잠재능을 이용하여 다년도(2009~2014년) 분석을 수행한 후, 현재 방식의 그룹화가 아닌 잠재성 및 위험성을 구성하는 세부 항목의 경향성(변화 추이)에 주목하여 비교 분석하였다. 그 결과, 기존 및 개선(안)에 대한 정확한 평가를 할 수 있었으며, 그에 따라 취약 순위를 도출할 수 있었지만 기존 방법은 실제 유역 경향과는 상이한 결과가 도출되었다. 따라서, 유역내의 홍수취약성 세부 항목 평가를 위해서는 과거 이력과 유역 특성을 제대로 반영한 개선(안)의 홍수피해잠재능이 보다 더 타당한 것으로 판단되며, 이를 참고한 치수 계획을 수립하여 홍수 피해를 사전에 방지하는 것이 합리적이라 생각된다.