• 상하수도학회지
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• 제19권5호
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• pp.557-564
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• 2005

The objective of this study is to evaluate a criteria of intercepting capacity and a reduction goal of overflow pollution load in combined sewer system. In the current criteria of intercepting capacity in the domestic sewage facility standard, it is known that three times of peak sewage (Q) in dry period or runoff flow by 2mm/hr is not appropriate since the intercepted flow is estimated by runoff and show different result even in the same watershed. Though a reduction goal of overflow pollution load can be determined from 1) same level of storm-water runoff pollution load in separated storm sewer, 2) less than 5% sewage load in dry weather period, by the domestic sewage facility standard, the simulated results from storm-water model show large differences between two criteria. While it is predicted that sewage pollution load standard three time larger than separated storm sewer standard in high population density and urbanized area, it is shown that separate storm sewer standard larger than sewage pollution load standard in middle population density and developing area. Accordingly, it is proposed that more reasonable intercepting flow and reduction goal of overflows pollution load should be established to minimize discharging pollution load in combined sewer systems. For the purpose, a resonable standard has to be amended by pollution load balance considering the characteristics of a watershed for generation, collection, treatment, and discharging flow.

• 상하수도학회지
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• 제19권5호
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• pp.547-556
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• 2005

The objective of this study is to obtain adequate intercepting flow during wet weather conditions in combined sewer system. Two study sites are selected under considering different population density, one is developed area with heavy urbanization. Another is recently developing area. In the analysis of field investigation, SS was most significant in initial flushing effects compared with other factors and showed the result with the order of COD, TP, TN. As compared with event mean concentration(EMC) of runoff, BOD, TN and TP showed high concentrations in wide area with relatively large population density. It is by the reason that much pollution load was discharged to receiving water from urbanized area during wet period. According to results of storm-water modeling, 53% of total COD and 52% of total SS pollution load were discharged to receiving water by overflow than intercepting capacity in middle population density site. Also, in the urbanized area, pollution load was discharged to receiving water by 49% of total COD and 77% of total SS. These results can be applied to setup for pollution load flow(budget) generation, collection, treatment and discharging in order to obtain adequate intercepting flow.

• 한국방재학회 논문집
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• 제4권4호
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• pp.21-26
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• 2004

우천시 합류식 하수도의 월류수(CSOs)에 의한 오염부하량을 감소하기 위한 대책으로 차집량의 결정은 매우 중요하다. 오염부하량 감소를 위한 대책으로 우수를 전량 차집하여 처리하는 것이 가장 바람직하겠으나, 시설의 규모와 기타 유지 관리면에서 합리적이지 않다. 본 연구에서는 배수구역의 유역형상, 면적, 강우시 차집량 등을 변화시키면서 이로 인해 변화하는 합류식 하수관거의 유랑과 수질 등을 분석하였으며, 계획차집량의 변동에 다른 CSOs의 영향을 파악함과 동시에 합류식과 분류식을 각각 비교해 봄으로서 하천에 방류되는 오염부하량의 정도를 비교해 보았다.

• 상하수도학회지
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• 제26권6호
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• pp.735-745
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• 2012

Storage method is one of major measures for reduction of CSOs pollutant loads and several projects have been done nationwide. But systematic analysis of intercepting capacity has not been studied to determine optimum size of storage facility. In this research, not only storage volume but also intercepting capacity which means flow capacity from intercepting facility to CSOs storage facility was studied and optimum sizing method for storage facility was proposed. The result shows that pollutants reduction efficiency can be increased significantly by increasing intercepting capacity and it might reduce storage volume and total construction costs. Intercepting capacity for the study area was evaluated and it was shown as equivalent to 83 % probability rainfall intensity.

• 한국산학기술학회논문지
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• 제9권1호
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• pp.129-135
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• 2008

하천으로 유입되는 합류식월류수(Combined Sewer Overflows, CSOs)는 하천의 수질 오염에 영향을 끼치게 되며 월류량은 차집관거의 설계용량에 따라서 결정되어진다. 따라서 차집관거의 기준 용량은 강우 유출의 특성 및 수질을 고려하여 합리적으로 결정되어야한다. 그러나 국내의 차집관거 기준 용량은 일괄적으로 시간최대오수량의 3배로 책정되어있으며, 강우-유출의 특성을 고려하지 않은 채 모든 지역에 대하여 균일하게 적용되어왔다. 따라서 본 연구에서는 강우유출 특성을 고려하여 강우 데이터에 대한 통계적 분석을 통하여 차집관거의 기준 용량을 결정하기 위한 기준 강우를 산정하였다. 서울지역의 평균개념의 확률강우량을 통하여 산정된 기준강우의 지속시간은 4hr이며 강우량은 재현기간 1.5년에 해당하는 6.76mm로 산정되었다. 또한 산정된 기준 강우를 적용하여 강우유출 특성 분석은 SWMM을 이용하였으며 이를 통하여 CSOs를 계산하였다.

• 상하수도학회지
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• 제18권4호
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• pp.418-424
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• 2004

An abrupt high pollution loads in combined sewer systems is believed to be caused by first flushing actions and the resuspension of sediments deposited in sewers. Therefore, pollution loads in each flow regulator have a different tendency. This systems control intercepting flow in each flow regulator using water quality and water level. A desired quantity of intercepting flow was adjusted and the necessary slide position for a constant intercepting is calculated by Optimization programming. This systems make it possible to reduce pollution loads caused by CSOs to water body, may be alternative for the stable operation of STP through improving water quality to STP.

• 상하수도학회지
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• 제14권2호
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• pp.181-195
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• 2000

The effect of the intercepting ratios on the water quality improvement was simulated by using Finite Segment Method in a urban river where intercepting sewer under the ground and constructing sewage treatment plant are now being proceeded. To simulate variations of the water quality caused by river flows, rating curve at each gaging station was derived from measurements. Water quality data were from the exiting observations at each key stations from 1990 to 1998, for 1999 and 2000 data we measured in creek and drainage ditch in addition to observation stations. It revealed that increasing the intercepting ratios improved the water quality.

• 상하수도학회지
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• 제33권3호
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• pp.177-190
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• 2019

The purpose of this study was to analyze the effects of sewerage facilities through I/I analysis by rainfall by selecting areas where storm overflow diverging chamber is remained due to the non-maintenance drainage equipment when the sewerage system was reconstructed as a separate sewer system. Research has shown that wet weather flow(WWF) increased from 106.2% to 154.8% compared to dry weather flow(DWF) in intercepting sewers, and that the WWF increased from 122.4% to 257.6% in comparison to DWF in storm overflow diverging chamber. As a result, owing to storm overflow diverging chamber of partially separate sewer system with untreated tributary of sewage treatment plant, rainfall-derived infiltration/inflow(RDII) has been analyzed 2.7 times higher than the areas without storm overflow diverging chamber. Meanwhile, infiltration quantity of this study area was relatively higher than that of other study areas. Therefore, it is necessary to reduce infiltration quantity through sewer pipe maintenance nearby river. Drainage equipment maintenance should be performed not to operate storm overflow diverging chamber in order to handle the appropriate sewage treatment plant capacity for rainfall because it is also expected that RDII due to rain will occur after maintenance. In conclusion, it is necessary to recognize aRDII(allowance of rainfall-derived infiltration/inflow) and to be reflected it on sewage treatment plant capacity because aRDII can occur even after maintenance to the complete separate sewer system.

• 대한환경공학회지
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• 제36권3호
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• pp.178-184
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• 2014

본 연구에서는 기존 CSOs (Combined Sewer Overflows) 모니터링에 비해 비용효과적이며 유지관리가 용이한 모니터링 시스템 구축의 적용성 검토를 위해 10.2 ha 규모의 배수면적이 포함된 우수토실에서 2회의 강우이벤트에 대해 전기전도도 데이터 및 토연모델을 이용하여 CSOs 유량 및 수질을 예측하였다. 강우이벤트별 전기전도도 희석률에 의한 유량예측결과 실측값과의 결정계수($R^2$)는 모두 0.86 이상으로 나타났으며, 다양한 강우이벤트에 적용이 가능한 예측식 산정을 위해 선행건기일수 및 강우지속기간 2가지를 추가 매개변수로 고려하여 회귀식을 보정한 후 적용한 결과 전기전도도 희석률만을 고려한 결과에 비해 $R^2$는 0.50에서 0.80, 오차범위 40% 이내에 포함된 상대오차 누적빈도는 54.1%에서 68.5%로 예측값의 정확도가 개선되었다. CSOs 수질은 별도의 입력자료 없이 매개변수의 보정만으로 예측값 산정이 가능한 토연모델을 적용한 결과 강우 이벤트별 실측값과의 $R^2$는 BOD 0.64~0.97, SS 0.70~0.95의 범위를 나타내었다.

• 한국습지학회지
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• 제9권3호
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• pp.25-34
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• 2007

본 연구는 도심지 유역인 경기도 부천 여월동 단지 내의 도시하천에 대해서 유출 및 홍수 특성을 분석하였다. 해당 유역의 하천은 차집 관로에 의한 생활하수와 흐름의 차단으로 인하여 평상시에는 매우 적은 유량만이 흐르고 있으나, 홍수 시에는 상대적으로 높은 홍수위로 인해 홍수 피해의 위험성을 보이고 있다. 홍수에 대한 안전성을 확인하기 위하여 유출 해석 모형을 적용하고, 또한 해당 유역에 대해 구축된 GIS 자료 및 하천 단면과 HEC-RAS를 이용, 홍수위를 예측하여 이를 바탕으로 해당 하천의 치수 안정성을 검토하였다. 검토 결과 다목적 소하천을 목적으로 설치된 하천 구조물로 인하여 홍수 피해 발생 위험이 있었으며, 하천 안정성에 대한 불안요소를 포함하고 있었다. 이러한 단지내 소규모의 도시유역에 대한 홍수 유출 해석에서는 홍수 유출 외에도 구조물에 의한 배수위 변동과 유속 등과 같은 여러 위험 요인에 대하여 함께 고려해야 할 것으로 판단된다.