• 한국수자원학회논문집
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• 제45권8호
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• pp.767-782
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• 2012

일반적으로 관거 및 맨홀 등의 도시 배수 시스템에서의 유사 및 유송잡물의 퇴적은 유수 흐름의 저항, 합류식 하수도의 조기 운영 및 도시 침수 및 주수로에서의 필연적인 오염 발생 등의 하수도 시설에 심각한 영향을 미친다. 그러므로 배수관과 연결된 합류맨홀에서 유사의 거동 특성 및 퇴적 양상을 분석할 필요가 있다. 본 연구에서는 문헌조사 및 현장조사를 실시하여 실험장치를 제작하고 실험조건을 선정하였다. 선정된 실험조건인 맨홀 형상 조건(사각형, 원형), 유사 유입 조건, 유입 유사량 및 유사 유입 관거를 변화시키면서 실시하였다. 맨홀 내부에 경사형 benching을 설치한 개선형 합류맨홀은 맨홀의 형상에 관계없이 합류맨홀 내 유사퇴적을 저감시키는 데에 상당한 효과를 나타내고 있으므로 도시 배수 시스템에서 개선형 합류맨홀은 관거 시설의 배수능력을 증대시킬 것으로 판단된다.

• 한국방재학회 논문집
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• 제6권2호
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• pp.51-60
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• 2006

본 연구의 목적은 유전자 알고리즘(Genetic Algorithm), 음정탐색법(Harmony Search)과 같은 발견적 방법과 동적계획법과 같은 최적화 기법들이 분기형 우수관망시스템의 최적비용 설계법에 적용됨에 있어 효율성을 비교하는데 있다. 이 목적에 맞추어 본 연구에서는 두 개의 우수관거 설계모형을 개발하였다.. 하나는 SEWERGA이고 다른 하나는 SEWERHS로서 각각의 모형은 결정변수로 최적의 파이프 매설깊이를 채택하였다. 이 두 모형은 유량과 유속의 제약조건을 만족시키는 가운데 파이프의 적절한 매설깊이에 따른 최적관경도 결정한다. 이 두 모델을 1975년 동적계획법(Dynamic Programming)을 이용하여 Mays와 Yen에 의해 계산된 예제에 적용하였다. SEWERGA와 SEWERHS에 의해 계산된 결과는 동적계획법에 의한 연구결과보다 약 4%의 비용 절감 효과가 있는 것으로 나타났다.

• 한국산학기술학회논문지
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• 제9권3호
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• pp.771-778
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• 2008

남강 상류에 하수도 시설의 보급률을 현행 20.8%에서 65.2%로 향상시켰을 경우 남강과 덕천강 그리고 진양호의 수질 변화를 파악하기 위하여 QUAL2E 모형과 WASP 7 모형을 이용하여 목표연도인 2011년의 BOD, TN, TP의 농도를 모의하였다. 수질 예측시나리오는 3가지로 구분하였다. 1) 하수도 시설이 현재와 같을 경우, 2) 하수도 시설의 확충으로 BOD, TN, TP가 각각 사업 목표 저감량인 2350.5kg/d, 216.0kg/d, 44.0kg/d 저감되었을 경우의 수질을 모의하였다. 또한 3) 남강과 진양호가 1급수가 되기 위해 저감해야 할 오염물 배출량을 모의하였다. 수질 모의 결과 남강 상류에서 하수도 보급률을 향상시켰을 경우 하천의 수질은 평균적으로 BOD 7.69%, TN 2.10%가 개선되는 것으로 나타났으며, 진양호의 수질은 BOD 10.25%, TN 1.37%, TP 2.94%가 개선되는 것으로 나타났다. 하지만 하수도 시설의 확충으로 남강과 진양호의 수질을 1급수로 유지할 수는 없는 것으로 모의되었다. 남강과 진양호를 1급수로 유지하기 위해서는 BOD의 배출량을 각각 27.2%, 37.05% 감소시켜야 하는 것으로 나타났다.

• 상하수도학회지
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• 제31권6호
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• pp.551-566
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• 2017

As the modern society is rapidly developing and people become affluent in materials, many new chemical compounds in different forms of products (e.g., antibiotics, pesticides, detergents, personal care products and plastic goods) are produced, used, and disposed of to the environments. Some of them are persistently having a harmful impact on the environment and mimicking endocrine properties; in general they are present in the environment at low concentrations, so they are called organic pollutants. These organic micropollutants flow to sewage treatment plants via different routes. In this study, the generation characteristics, exposure pathways, detection levels, and environmental impacts of organic micropollutants were critically reviewed. In addition, currently available risk assessment methods and management systems for the compounds were reviewed. The United States Environmental Protection Agency (US EPA), for example, has monitored organic micropollutants and set the monitoring and management of some of the compounds as a priority. To effectively manage organic micropollutants in sewer systems, therefore, we should first monitor organic micropollutants of potential concern and then make a watch list of specific substances systematically, as described in guidelines on listing water pollutants in industrial wastewater.

• 상하수도학회지
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• 제29권6호
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• pp.693-702
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• 2015

The objective of this study is to investigate and evaluate that a roadside tree root intrudes sewer network systems. Two approaches were performed to assess the characteristics of tree root intrusion. First, the characteristics of tree roots that had invaded sewers were directly observed by means of closed-circuit television inspection robot. Second, the intrusion proportions of tree root into rain gutters in the sampling area were investigated. As tree species of low intrusion proportions, the results indicated that Ginkgo biloba Linn. and Acer buergerianum Miq. were 1.7% and 4.3%. On the other hand, tree species of high intrusion proportions were Metasequoia glyptostroboides Hu et Cheng, Ulmus davidiana var. japonica Nakai and Zelkova serrata Makino as 22.2%, 20.4%, and 17.6% respectively. In particular, sewers and gutters around Zelkova species should be the focus of maintenance work because of the high proportion of these trees on roadsides.

• 상하수도학회지
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• 제22권6호
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• pp.619-625
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• 2008

Urban sewer systems are designed to operate in open-channel flow regime and energy loss at square manholes is usually not significant. However, the energy loss at surcharged manholes is considered as one of the major causes of inundation in urban area. Therefore, it is necessary to analyze the head loss associated with manholes, especially in surcharged flow. Hydraulic experimental apparatus which can change the manhole inner profile(CASE I, II, III, and IV) and the invert types(CASE A, B, C) were installed for this study. The experimental discharge was $16{\ell}/sec$. As the ratio of b/D(manhole width/inflow pipe diameter) increases, head loss coefficient increases due to strong horizontal swirl motion. The head loss coefficients for CASE I, II, III, and IV were 0.46, 0.38, 0.28 and 0.37, respectively. Side covers increase considerably drainage capacity at surcharged square manhole when the ratio of d/D(side cover diameter/inflow pipe diameter) was 1.0. The head loss coefficients for CASE A, B, and C were 0.45, 0.37, and 0.30, respectively. Accordingly, U-invert is the most effective for energy loss reduction at surcharged square manhole. This head loss coefficients could be available to evaluate the urban sewer system with surcharged flow.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회 논문집
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• pp.1199-1203
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• 2005

Combined sewer overflows(CSOs) are themselves a significant source of water pollution. Therefore, the control of urban drainage for CSOs reduction and receiving water quality protection is needed. Examples in combined sewer systems include downstream storage facilities that detain runoff during periods of high flow and allow the detained water to be conveyed by an interceptor sewer to a centralized treatment plant during periods of low flow. The design of such facilities as stormwater detention storage is highly dependant on the temporal variability of storage capacity available(which is influenced by the duration of interevent dry periods) as well as the infiltration capacity of soil and recovery of depression storage. As a result, a contiunous approach is required to adequately size such facilities. This study for the continuous long-term analysis of urban dranage system used analytical Probabilistic model based on derived probability distribution theory. As an alternative to the modeling of urban drainage system for planning or screening level analysis of runoff control alternatives, this model have evolved that offer much ease and flexibility in terms of computation while considering long-term meteorology. This study presented rainfall and runoff characteristics or the subject area using analytical Probabilistic model. Runoff characteristics manifasted the unique characteristics of the subject area with the infiltration capacity of soil and recovery of depression storage and was examined appropriately by sensitivity analysis. This study presented the average annual COSs and number of COSs when the interceptor capacity is in the range 3xDWF(dry weather flow). Also, calculated the average annual mass of pollutant lost in CSOs using Event Mean Concentration. Finally, this study presented a dicision of storage volume for CSOs reduction and water quality protection.

• 한국수자원학회논문집
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• 제39권5호
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• pp.441-452
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• 2006

최근에 홍수재해와 관련된 자연재해가 급격히 증가하고 있다. 특히, 사회기반시설의 집중 및 인구증가로 도시지역에서의 침수는 인명과 재산에 큰 피해를 야기한다. 본 연구의 목적은 배수시스템에서의 과부하로 인한 도시지역에서의 침수심을 계산하기 위해서 우수배수시스템모형과 2차원 지표류모형을 연계한 새로운 모형을 개발하는 것이다. 대상유역에서의 침수유량의 거동은 두 가지 요소로 고려되는데 하나는 배수시스템에서의 흐름이고 다른 하나는 월류유량으로 발생한 범람 흐름으로 고려되어 졌다 개발모형은 군자와 장안유역에 적용되었고, 계산된 침수심들은 모의결과로 제시되었다. 모의 결과는 홍수관계기관이 침수 발생이 예상되는 지점에서 홍수피해 방지를 위해 배수시스템의 용량에 대한 재설계 혹은 확장 등과 같은 대책을 수립하는데 도움을 줄 수 있다. 또한, 본 모형은 홍수관계기관에서의 정책결정에 활용될 수 있도록 침수위험지도를 만들고 홍수경감대책을 수립하는데 이용될 수 있다

• 한국물환경학회지
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• 제23권4호
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• pp.490-497
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• 2007

A Combined sewer overflows (CSOs) are themselves a significant source of water pollution. Therefore, the control of urban drainage for CSOs reduction and receiving water quality protection is needed. Examples in combined sewer systems include downstream storage facilities that detain runoff during periods of high flow and allow the detained water to be conveyed by an interceptor sewer to a centralized treatment plant during periods of low flow. The design of such facilities as stormwater detention storage is highly dependant on the temporal variability of storage capacity available (which is influenced by the duration of interevent dry periods) as well as the infiltration capacity of soil and recovery of depression storage. As a result, a continuous approach is required to adequately size such facilities. This study for the continuous long-term analysis of urban drainage system used analytical probabilistic model based on derived probability distribution theory. As an alternative to the modeling of urban drainage system for planning or screening level analysis of runoff control alternatives, this model have evolved that offer much ease and flexibility in terms of computation while considering long-term meteorology. This study presented rainfall and runoff characteristics of the subject area using analytical probabilistic model. This study presented the average annual COSs and number of COSs when the interceptor capacity is in the range $3{\times}DWF$ (dry weather flow). Also, calculated the average annual mass of pollutant lost in CSOs using Event Mean Concentration. Finally, this study presented a decision of storage volume for CSOs reduction and water quality protection.

• 한국물환경학회지
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• 제36권3호
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• pp.206-219
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• 2020

As urbanization and impermeable areas have increased, stormwater and non-point pollutants entering the stream have increased. Additionally, in the case of the old town comprising a combined sewer pipe system, there is a problem of stream water pollution caused by the combined sewer overflow. To resolve this problem, many cities globally are pursuing an environmentally friendly low impact development strategy that can infiltrate, evaporate, and store rainwater. This study analyzed the expected effects and efficiency when the LID facility was installed as a measure to improve hydrologic cycle and water quality in the Oncheon stream in Busan. The EPA-SWMM, previously calibrated for hydrological and water quality parameters, was used, and standard parameters of the LID facilities supported by the EPA-SWMM were set. Benchmarking the green infrastructure plan in New York City, USA, has created various installation scenarios for the LID facilities in the Oncheon stream drainage area. The installation and maintenance cost of the LID facility for scenarios were estimated, and the effect of each LID facility was analyzed through a long-term EPA-SWMM simulation. Among the applied LID facilities, the infiltration trench showed the best effect, and the bio-retention cell and permeable pavement system followed. Conversely, in terms of cost-efficiency, the permeable pavement systems showed the best efficiency, followed by the infiltration trenches and bio-retention cells.