• Water for future
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• v.12 no.2
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• pp.56-62
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• 1979

Many methods of estimating design floods from rainfall data involve a trial and error procedure to determine the duration of the design rainfall, which is very complicated and time-consuming. In this study, an effort was given to derive an analytical expression for estimating the appropriate duration for use with a particular unit hydrograph. According to the so-derived analytical expression the coordinateds of hvdrograph curve and rainfall curve for the Musim Representative Basin were computed and then plotted on a same scal graph paper on which the critical durations of design rainfall excess of various recurrence intervals were determined by the point of intersection of the tow curves.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.1016-1020
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• 2010

본 연구는 충북 청주시에 위치한 무심천 주변을 대상으로 하천이 도시 주변 열 환경에 미치는 영향에 대해 원격탐사(Remote Sensing; RS)기법을 이용하여 분석하였다. 열 환경 특성 분석 순서는 먼저 Landsat 5 TM 위성영상의 열적외 밴드를 이용하여 대상지역의 표면 온도(Land Surface Temperature; LST)를 추출하였다. 다음으로 추출된 LST를 이용하여 무심천을 중심으로 주변의 공업단지와 주거지, 산림 지역의 지표면 온도 분포를 비교 분석하여 하천이 주변의 열 환경에 미치는 영향을 정량화하였다. 또한 공간적 특성 분석을 위해 등온선을 작성하여 하천 주변 열 환경을 파악하였다. 그 결과 온도분포에 따른 열 이동의 크기와 방향을 확인할 수 있었고 열 분포의 공간분포는 공업지>주거지>하천>산림 순으로 나타나 토지이용특성에 따른 열 분포의 경향을 파악할 수 있었다.

• Journal of the Korean Institute of Rural Architecture
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• v.17 no.2
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• pp.27-34
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• 2015

As part of the waterway restoration to renew traditional urban area, this paper is to assume and research Gyoseocheon(Gyoseo waterway) in Late 1960s Cheongju Korea. The main stream of Gyoseocheon flew from Sangjwagol(the head of the valley) of Uam Mt. to the north gate under Cheongju castle at first, and meandering from Sangdang Park, flew through Sudongseongdang and Bangadari Road to Musimcheon since open railroad of 1920s. This waterway, the eco-friendly figure of Gyoseocheon, that flew to inside the downtown with a planted tree and that is open space was so. The sub stream of Gyoseocheon originated in Seoundong and Tapdong were divided into two parts. One was to join the main stream of Gyoseocheon on Sangdang Park via Munhwadong, and the other was to join the sub stream of Musimcheon at northwest corner via south and west gate of Cheongju castle. This waterway as branch sewer were built into the road culvert.

• Journal of Environmental Impact Assessment
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• v.27 no.1
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• pp.73-82
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• 2018

The purpose of this study is the evaluation of the impact of increase in impervious areas due to urbanization on the pollutant discharge using the HSPF model at Musim watershed. Model calibration and validation were performed based on the observed data 2015 and 2014, all simulation items have been successfully simulated such as flow, BOD, and TP. The land cover map used in the model reflected on the land use status of the Musim watershed in 2015 and the application of the development areas and locations. As a result of simulation, during rainfall daily pollutant load with the increased impervious land increased more than that before the development. However, the pollutant load decreased during the non-rainfall time. Annual pollutant load in rainfall time was significantly higher than that in non-rainfall time, BOD and TP increased. The simulation of non-point source pollutant load was applied under two assumptions, such as the increased area of impervious land and the non-change number of point source load before and after development. As the result of a simulation, the non-point source pollutant load after development was bigger than those before development. It was necessary to take measures to control non-point source pollution at the consideration status of development.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.1905-1909
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• 2006

지하수 함양량을 정확하게 산정하는 것은 지하수계의 적절한 관리를 위해서 매우 중요하다. 국내에서 주로 사용되는 지하수 함양량 추정방법은 지하수위 변동법, 기저유출 분리법, 연단위 물수지 분석법 등이 있다. 그러나, 이들 방법은 집중형 개념을 기반으로 하기 때문에 기후조건, 토지이용, 토양조건, 수리지질학적 비균질성에 의한 함양량의 시공간적 변동성을 구현할 수 없다. 따라서 본 연구에서는 유역의 비균질성을 반영할 수 있는 SWAT 모형을 이용하여 시공간적 변동성을 고려한 지하수 함양량을 산정하는 방법을 제시하고자 한다. SWAT 모형은 유역내 일단위 지표면 유출량, 증발산량, 토양저류량, 함양량, 지하수유출량 등의 수문성분을 계산할 수 있는 모형이다. 본 연구에서는 SWAT 모형을 미호천 유역의 최상류인 무심천 유역에 적용하였다. 2001년 - 2004년까지의 기간동안 지하수 함양량을 포함한 유역의 일단위 수문성분들을 모의하였으며, 유역출구점에서의 실측 일유출자료와 모의 일유출자료의 비교를 통해서 모의결과의 유효성을 검토하였다. 지하수 함양량의 시공간적 변화를 분석한 결과, 지하수 함양량의 변동성은 토지이용 변화뿐만 아니라, 유역경사와 같은 지형인자에도 큰 영향을 받는 것으로 분석되었다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.2
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• pp.295-305
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• 1993

The purpose of this study is to investigate the theoretical methodology for development of an water quality management system with the optimal control of dilution water and point sources in streams. For the development of objective function and constraints, the control vectors are defined with stream inflows and concentrations of effluents at water treatment plant, and the state vectors are defined with water quality parameters such as DO, $BOD_5$, COD and SS concentrations. The applied system solution technique is augmented Lagrangian technique. The developed water quality optimal management methodology was applied to a case study at the Musim stream in Cheong-ju city. The results of the application show that the methodology is suitable for the comprehensive analysis of polluted water systems, and will be utilized to more useful operation of limited water resources in Korean streams.

• Journal of Environmental Impact Assessment
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• v.18 no.1
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• pp.1-9
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• 2009

Even though the center of Cheongju city needs redevelopment because of a doughnut phenomenon, it has to be permitted within the environmental carrying capacity like a target water quality proposed on the Total maximum daily loads(TMDL) of Musim and Miho river watersheds. The aim of in this study is to identify the limit of redeveloping Cheongju downtown after analyzing its environmental carrying capacity using QUAL2E model. As a result of modeling various scenarios, the water quality of Musin river was shown that $BOD_5$ is 2.3mg/L which is the target water quality in the double of existing development plan of the Cheongju downtown. The water quality of Miho river was $BOD_5$ 3.97mg/L which is less than the target water quality of Miho B watershed in the same condition. Therefore, this means that the limit of redevelopment within the environmental carrying capacity of cheongju downtown was estimated to be the double of existing development plan.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.941-941
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• 2012

최근 이상기후로 인한 강우량 증가와 집중호우가 빈번히 발생하고 있는 추세이다. 작년 서울지역의 하루 강우량은 301.5mm, 1시간 최대 강우량이 113mm를 기록하였고, 침수와 산사태 인한 인적, 물적 피해가 나타나면서 재해위험이 크고 예측한계를 벗어난 특이기상 발생빈도가 증가했다. 강수일수 또한 1980년대 36일에서 2011년 48일로 빠르게 증가하고 있다. 본 연구에서는 특이기상 발생 원인을 강우량으로 고정하여 확률강우량 증가에 따라 홍수량의 변화양상을 해석하였다. 변화한 홍수량이 홍수위에 미치는 변화양상을 분석하기 위해 금강수계의 무심천유역에 위치한 청주강우관측소를 선정하였고, 대상유역의 확률강우량을 증가시켜 빈도해석을 통한 각각의 재현기간에 발생한 면적확률강우량을 산정하였다. 또한 GIS 프로그램을 이용해 지형인자를 추출하고 추출된 지형인자를 이용하여 매개변수를 산정하였다. HEC-HMS 모형의 계산조건에서 손실우량은 SCS CN, 유출변환은 Clark 단위도법을 적용하였다. 그리고 HEC-RAS 모형에서는 자연하천에 주로 적용하는 부등류 모델링을 수행하여 결과값의 조건별 양상을 분석하였다. 분석결과 확률강우량 증가율에 대한 홍수량은 비슷한 변화율을 보여주었고, 홍수량 증가에 대한 홍수위 변화율은 동일한 비율만큼 반영되지 않음을 판단할 수 있었다.

• Water for future
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• v.9 no.2
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• pp.101-114
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• 1976

This paper presents a hydrologic method of probabilistic design flood calculation for ungauged small river basins. It is based on the study and analysis of the physiographic characteristics of the river basin for which stream flow records may not be available. Rainfall data is used at nearby station which has the rainfall intensity-duration-frequency relations. Musim cheon, second tributary of the Guem river, is selected for the sample study. Design floods for the stream reaches are computed by the Rational formula, the runoff coefficients being determined with the physiographic data such as soil type, land use and vepetal covers. Derived unit hydrograph at conneted main river basin is used to compute the peak flood discharge. Kajiyama formula and modified Kajiyama formula are used to calculated the most probable maximum flood discharge. The result of this study shows that synthesized unit hydrograph method is more accurate and applicable way to com pute design flood for ungauged small river basins.

• Journal of Environmental Impact Assessment
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• v.26 no.1
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• pp.57-67
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• 2017

Recently, Looking at the watershed management policy in Korea, It is preparing to manage sub-watershed and tributary from the government-led mainstream management, such as the selection of algae focused management tributary, application of tributary-TMDLs. At this point, this study is attempted to propose the residents participatory watershed management methods that is possible daily, voluntary and customized management in the sub-watershed. As a results, through this study, we found out the importance of sub-watershed unit based watershed management because of the pollutants in blind spot. It is the prerequisite for watershed management to arrange practicable bottom-up approach that these investigated contents can be reflected in the various planning.