• 대한환경공학회지
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• 제38권10호
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• pp.558-565
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• 2016

낙동강 195개 지류 지천 지점에서 2015년 수집된 699회의 유량 및 BOD/COD/T-N/T-P/SS/TOC 농도 등의 수질 자료를 이용하여 중점관리지점 선정 연구를 수행하였다. 각 모니터링 지점에서 BOD, T-P, TOC 농도 및 오염부하량에 대한 변동계수가 매우 크게 확인되어 1년 평균 자료를 이용한 중점관리지점 선정이 경우에 따라 불합리할 수 있을 것으로 지적되었다. 이러한 이유로 본 연구에서는 각 모니터링 자료를 평균화하지 않고 독립적으로 이용할 수 있는 두 가지 방법을 제시하였다. 첫 번째 방법으로 각 모니터링 시점별로 수집된 BOD, T-P, TOC 농도를 낙동강 중권역별 목표수질과 비교하여 목표수질을 초과하는 횟수를 각 지점별로 산정하였다. 두 번째로 BOD, T-P, TOC 항목에 대한 오염부하량을 각 모니터링 시점별 및 지점별로 산정하여 % 순위를 산정하는 방법을 적용하였다. 이상의 방법을 통해 결정된 중점관리지점을 서로 비교하였으며, 이를 통해 낙동강 유역의 수질의 전반적 특성을 분석하였다.

• 상하수도학회지
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• 제36권5호
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• pp.289-296
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• 2022

Mangyeong River and Dongjin River are highly dependent on external regions for domestic and agricultural water, and the agricultural water supply and use system of those rivers are very complicated. For smooth water supply, rivers are used as a supply system. Of the total river water use permits (as of 2019), agricultural water accounts for 97.5%, 80.4% in Mangyeong River and Dongjin River, respectively. The excessive intake of river water as agricultural purpose is causing the stream to dry out and to deteriorate the ecological health of the river. It is necessary to minimize the water use system that takes in and utilizes river water. In both rivers, the flow rate of agricultural drainage and the load of major water quality items that flowing into the main stream are similar to or higher than those of the major tributaries, indicating that management is necessary to improve the water quality of the river. It is necessary to understand the effect of agricultural drainage on river water quality by establishing a continuous monitoring system for the form of agricultural drainage.

• 한국물환경학회지
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• 제29권4호
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• pp.540-550
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• 2013

Temporal increase of SS induces concentrations in various forms of organic matter including BOD, COD, TOC. Consequently, it causes hard to identify sources of water pollution during or after precipitation. The objective of this study is to investigate variations of DOC concentration caused by increase of flow and changes of external factors in river by comparing to SS concentration. In results, monitoring sites (e.g., Banbyeonchen) consisting of hard riverbed showed high correlation between SS and organic matters, except BOD. On the contrary, other sites (e.g., Naesungcheon) where riverbed consists of sand were found in a wide range of annual fluctuation in SS level, whereas these sites showed a narrow range in annual DOC fluctuation. In Gumhogang and Namgang, a lower correlation between SS and other factors was found most likely because of high concentration in organic matter. However, lower annual fluctuation values of DOC were observed in comparison to those of COD and TOC. Similar results were also confirmed in main river sites, Sangju and Mulgeum. In conclusion, DOC concentration is better indicator for monitoring organic matter which cannot be provided by BOD, COD, TOC in the Nakdong river basin.

• 한국지형학회지
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• 제26권4호
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• pp.1-20
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• 2019

In order to establish appropriate policy to control sediment-associated problems, it is necessary to identify the physical characteristics of the reservoir sediments in particulate form in the Yeongsan River. Two time-integrated suspended sediment samplers were installed at Seungchon and Juksan weir on the upper and middle Yeongsan River in July 2012. Reservoir sediment samples were obtained at monthly intervals until October 2014. During the monitoring period, a total of 38 sediment samples were obtained and analyzed. Seasonal trends of suspended sedimentation rates and grain size distributions were examined based on variations in precipitation and discharge fluctuations. Moreover, stream flow characteristics, which has a great influence on the physical characteristics of the river sediment, was analyzed using flow duration curve for the period 2003-2019 at Naju gauging station. Sedimentation rates during summer, when heavy rainfall was concentrated due to the monsoonal front and typhoon, were very high, indicating the positive relationship between sediment concentration and discharge. Particle size analysis of the collected sediment showed that coarse silt and very fine sand-sized sediment dominated most of the Seungchon weir sediment. On the other hand, medium silt-sized sediment dominated the downstream Juksan weir except for a few summer samples. These results implied that the physical characteristics of the suspended sediment are determined not only due to flow fluctuations, but also with regard to the antecedent rainfall conditions, hillslope-channel connectivity, and the supply of materials from various contributing regions. This information about flow characteristics and temporal variations in reservoir sediment can be used for safe management of the weir and discussing the issues on the dismantling of the weirs.

• 한국물환경학회지
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• 제28권4호
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• pp.538-550
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• 2012

This study suggests a general methodology which is designed for assessing RDOC behavior at the catchment scale by coupling properly a series of steam flow and water quality simulation models and actual monitoring data set. The modified TANK model in which a river routing function is incorporated to the conventional one is applied to simulate the long-term daily stream flow data, and the simulated stream flow data is combined with the 7-parameter log-linear model coupled to the minimum variance unbiased estimator to simulate the long-term daily water quality (BOD, COD and TOC) loads. Finally, the regression analysis between the usually monitored water quality data (BOD, COD and TOC) and RDOC is combined with the simulated water quality data to manifest the spatio-temporal variability of RDOC flux behavior at the Korean TMDL catchment scale.

• 한국물환경학회지
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• 제21권5호
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• pp.516-519
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• 2005

An useful protocol coiled load duration curve methodology to estimate contaminant loading to a river on an exceedance probability scale was developed in this research. The technique was further applied to estimate total coliform loading to the Geum River, using the daily mean flow rate and total coliform concentration data during January, 1996 and July, 2004 for the Gongju where an automated monitoring station is located. Drought flow of the Gongju (=50.3 cms) was equivalent to 40% on an exceedance probability scale. Load duration curve for total coliform loading at the Gongju was constructed. Standard duration curve was constructed with the water quality criteria for the class 2 (total coliform concentration = 1000 MPN/100 mL). By plotting load duration curve with standard duration curve, it could be revealed that water quality do not meet the desired water quality for 47% on an exceedance probability scale. If linearity between flow rate and coliform concentration is assumed, it can be interpretated that water quality exceeds desired criteria when average mean flow rate is over 51 cms.

• 한국수자원학회논문집
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• 제52권spc2호
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• pp.855-863
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• 2019

어류의 어도 이용효율평가를 위해서는 유인효율과 통과효율로 분리하여 분석할 때, 각각의 효율을 증대시킬 수 있는 방향으로 어도 설치 및 관리 계획이 수립될 수 있다. 기 설치된 어도는 어류 모니터링을 통해 보다 직접적으로 각각의 효율을 평가할 수 있다. 반면 어도를 계획할 때, 또는 여건상 어류 모니터링이 어려운 경우, 수리해석을 통해 간접적으로 어도 효율을 평가할 수 있다. 본 연구에서는 어도의 효율평가가 가능한 수리해석 기법을 제시하였다. 유인효율 분석에는 어류 물리서식처 모듈이 장착된 River-2D모형을 사용하였고, 효율의 지표로 가중가용면적을 제안하였다. 통과효율 분석에는 자유 수면을 가지고 수리구조물상의 유체거동을 해석할 수 있는 3차원 모형(Flow-3D)을 해석 도구로 이용하였다. 그리고 덕천강 백곡보에 설치된 아이스하버 어도를 선택하여 어도 효율을 가늠해 보았고, 실제 어류 모니터링자료와 비교해 보았다. 그 결과 수리해석 자료를 정량적으로 어도 효율로 치환하기는 어렵지만, 대체적인 경향성 파악에는 도움을 줄 수 있었다.

• 물과 미래
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• 제29권2호
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• pp.167-178
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• 1996

하천 및 호소수 수질의 온라인 계측을 위한 수질자동측정망의 설계에서 측정위치와 항목의 선정은 전체시스템의 성능을 결정짓는 중요한 인자이다. 본 논문에서는 상수원유역의 상시수질감시 및 사전경보 기능을 갖는 측정망의 구축이 측정위치와 항목을 결정하는 방법을 연구하였다. 측정위치를 결정하기 위한 선정기준은 상수취수량과 고정오염원의 위치를 바탕으로 대상지역에 대한 거시적 후보지점을 선정한 뒤, 구체적인 지점은 오염물질 유하거리를 기준으로 단계적으로 결정한다. 측정항목은 유역의 오염특성과 수질오염사고 이력을 참고하되, 경제적인 측면을 고려하여 필수측정항목과 선택항목으로 나누어 위치별로 달리하는 방안을 제시하였다. 제안방법을 낙동강유역에 적용함으로써 측정망 구성과정을 예시하였다.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.707-710
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• 2008

Recently, a rivers' bridge that locate on among the mountains area is destroyed by debris accumulation and debris flow, because of frequent occurrence of typhoon and a localized torrential downpour. therefore a river make a part of dam's effect. Actually, this situation gives damages like inundation of a bridge upper stream area's. Generally, It the main cause of the occurrence route of the debris accumulation is that outbreaks of driftwood and debris flow because of landslide, that occurred by severe rain storm. Also, a lot of debris are occurred when big flood come up during long period at this time, this kind of debris accumulation remove to other place, in several, and specially, debris accumlation move to the place where the depth of water is deep and velocity is fast river center. According to these kind of fact, this research put in effect and analyze that movement characteristic's numerical simulations of debris accumulation at flood according to a domestic outside literature investigation, on-site monitoring survey and parameter scenario which comes out through the hydraulic modeling analysis.

• 한국물환경학회지
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• 제34권1호
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• pp.1-9
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• 2018

In this study, the load of the river was calculated by using the actual data of the Yeong-bon C1, Yeong-bon C2, Yeong-bon C3 monitoring points of the Yeong-san river watershed to determine the excess. As a result, the BOD is 75.83 % at the Yeong-bon C1 and the five-year average value is higher than at other points. The Yeong-bon C3 was 72.15 % and Yeong-bon C2 was analyzed as 68.78 %. The five-year average of the T-P was 71.95 % for the Yeong-bon C2 and 69.86 % for the Yeong-bon C3 and 69.16 % for Yeong-bon C1; these levels exceeded the target water quality standards of 50 %. As a result of analyzing the pollutant load, we found that the Yeong-bon C1 has been highly affected by the nonpoint pollution source because the excess rate is high in the upper section of the flow rate. The Yeong-bon C2 showed a high excess rate in the lower part of the flow rate, and it was estimated that the influence of the point pollution source was large. The excess rate of the Yeong-bon C3 is small in the interval deviation, and it was evaluated as being affected by both point and non-point pollution sources. The TMDL monitoring network data were used to estimate the exceed ratio for the target water quality assessment, and the implementation evaluation was made by the flow exceedance probability interval to analyze the monitoring data so that the data could be utilized according to the purpose of the measurement network.