• 한국습지학회지
• /
• 제14권4호
• /
• pp.581-589
• /
• 2012

비점오염원은 유역 및 지역의 토지이용 형태별로 강우유출수의 유출특성이 다양하고, 강우시 지표면의 각종 오염물질들이 도시하천으로 유입되어 수질에 심각한 영향을 미치고 있다. 본 연구에서는 도시지역을 주택 및 공단구역으로 구분하여 강우유출수의 유출특성을 파악하고자 오염물질별 EMC를 산정하였다. 분석 결과 강우시 주택 및 공단지역의 비점오염원은 강우초기에 유출수의 농도가 급격히 증가한 후 서서히 감소하는 초기세척현상이 발생하였으며, 초기우수의 제어가 필요하였다. 향후 장기적인 강우사상 및 수질조사 자료의 축척, GIS를 이용한 토지이용형태, 지형 및 지질특성의 자료 축척 등 지속적인 연구가 필요할 것으로 판단된다.

• 상하수도학회지
• /
• 제19권2호
• /
• pp.117-124
• /
• 2005

Appropriate removal of pollutants from combined sewer overflows(CSOs) and stormwater runoff is of primary concern to watershed managers trying to meet water quality standards even under a wet weather condition. Harmful substances associated with particles besides TSS and BOD are subjected to removal prior to discharge into the natural waters. Effectiveness of five major hydrodynamic separation technologies, Vortechs, Downstream Defender including Storm King for CSOs control, CDS, Stormceptor, and IHS, were evaluated in this study. There is not sufficient information for accurate evaluation of the removal efficiency for the pollutants from the stormwater runoff and CSOs. Based upon limited engineering data, however, all technologies were found to be effective in separation of heavy particles and floating solids. Technologies utilizing screens seem to have advantage in the treatment capacity than the other technologies relied fully on hydrodynamic behavior. The IHS system seems to have a strong potential in application for control of CSOs because of unique hydrodynamic behavior as well as a flexibility in opening size of the screens. Size of the particulate matter in the CSOs and stormwater runoff is found to be the most important parameter in selection of the type of the hydrodynamic separators. There exists an upper limit in the solids removal efficiency of a hydrodynamic separator, which is strongly dependent upon the particle size distribution of the CSOs and stormwater runoff.

• 대한토목학회논문집
• /
• 제36권3호
• /
• pp.395-406
• /
• 2016

도시화로 인한 인구집중 및 개발 집중현상으로 하천변 저지대 및 지하공간 사용이 증가하였고, 불투수층이 증가하여 도시유역의 배수체계는 우수관거에 의존하고 있다. 이러한 변화로 인한 우수관거의 저류용량 부족 및 외수위의 영향으로 인한 도심지 역류 현상으로 인한 침수피해가 발생하고 있다. 하지만 기존의 홍수범람에 관한 연구는 대부분 외수범람과 내수침수를 유기적으로 연결하지 못하고 있다. 본 연구에서는 상습침수가 발생하는 도시유역에 대하여 도시유역 유출특성을 고려한 홍수의 정확한 예측을 위해 강우분석 및 외수위를 고려하고, 도시유출모형인 SWMM 모형을 이용하여 하수관거의 월류를 분석하였고, 이 결과를 홍수범람해석 모형과 연계하여 도시유역에서의 집중호우 발생시 침수해석을 실시하여 수방시설물의 홍수배제 효율을 분석하였다. SWMM 모형의 적용결과 외수위영향에 따른 원활한 내수배제가 불가능 한 것으로 나타났고, 관거 월류량이 많아진 것으로 나타났다. 월류된 우수가 지면을 따라 흐를 경우 저지대의 침수가 예상되고, 월류량이 많은 맨홀을 주요맨홀로 선정하였고, 월류수 저감을 위한 방안으로 주요 맨홀의 인근 지역에 저류지를 설치하는 방안과 각 맨홀들을 연결하는 관거를 확대하는 방안을 설정하였다. 월류 저감 시나리오 적용 결과 저류지 설치시 월류량의 45%, 관거 확대시 33~64%의 저감효과를 보였다. SWMM 모형의 결과를 이용하여 홍수범람해석 모형을 모의한 결과 지표경사와 도로를 따라 맨홀 월류수가 모여 침수현상을 발생시키는 것으로 나타났으며, 관거 확대 적용시 침수면적이 19.6%, 60.5% 줄어든 것으로 나타났다.

• Environmental Engineering Research
• /
• 제17권3호
• /
• pp.167-174
• /
• 2012

In situ particle size spectra are obtained from two sequent cruises in order to evaluate the physical consequences of suspended particulate matters caused by episodic storm runoff from the Santa Ana River watershed, an urbanized coastal watershed. Suspended particles from various sources including surface runoff, near-bed resuspension, and phytoplankton are identified in empirical orthogonal function (EOF) analysis and an entropy-based parameterization (Shannon entropy). The first EOF mode is associated with high turbidity and fine particles as indicated by the elevated beam attenuation near the Santa Ana River and Newport Bay outlets, and the second EOF mode explains the suspended sediment dispersal and particle coarsening at the near-surface plume. Chlorophyll particles are also distinguished by negative magnitudes of the first EOF mode, which is supported by the relationship between fluorescence and beam attenuation. The integrated observation between the first EOF mode and the Shannon entropy index accentuates the characteristics of two different structures and/or sources of sediment particles; the near-surface plumes are originated from runoff water outflow, while the near-bottom particles are resuspended due to increased wave heights or mobilizing bottom turbidity currents. In a coastal pollution context, these methods may offer useful means of characterizing particle-associated pollutants for purposes of source tracking and environmental interpretation.

• 한국물환경학회지
• /
• 제29권2호
• /
• pp.184-195
• /
• 2013

Urbanization from agricultural/forest areas has been causing increased runoff and pollutant loads from it. Thus, numerous models have been developed to estimate NPS loading from urban area and Long-Term Hydrologic Impact Analysis (L-THIA) model has been used to evaluate effects of landuse changes on runoff and pollutant loads. However, the L-THIA model could not consider rainfall intensity in runoff evaluation. Therefore, the L-THIA model, capable of simulating runoff using 10-minute rainfall data, was applied to the study areas for evaluation of estimated runoff and NPS. The estimated Nash-Sutcliffe coefficient (NSE) values were over 0.6 for runoff, BOD, TN, and TP for most sites and watershed. The calibrated model was further extended to other counties for pollutant load potential evaluation. Pollutant load potential maps were developed and target areas were identified. As shown in this study, the L-THIA 2012 can be used for evaluation runoff and pollutant loads with limited data sets and its estimation could be used in identifying pollutant load hot spot areas for implementation of site-specific Best Management Practices.

• 한국물환경학회지
• /
• 제26권1호
• /
• pp.61-70
• /
• 2010

The increase of impervious cover (IC) in a watershed is known as an important factor causing alteration of water cycle, deterioration of water quality and biological communities of urban streams. The study objective was to assess the impact of IC changes on the surface runoff characteristics of Kap Stream basin located in Geum river basin (Korea) using the Storm Water Management Model (SWMM). SWMM was calibrated and verified using the flow data observed at outlet of the watershed with 8 days interval in 2007 and 2008. According to the analysis of Landsat satellite imagery data every 5 years from 1975 to 2000, the IC of the watershed has linearly increased from 4.9% to 10.5% during last 25 years. The validated model was applied to simulate the runoff flow rates from the watershed with different IC rates every five years using the climate forcing data of 2007 and 2008. The simulation results indicated that the increase of IC area in the watershed has resulted in the increase of peak runoff and reduction of travel time during flood events. The flood flow ($Q_{95}$) and normal flow ($Q_{180}$) rates of Kap Stream increased with the IC rate. However, the low flow ($Q_{275}$) and drought flow ($Q_{355}$) rates showed no significant difference. Thus the subsurface flow simulation algorithm of the model needs to be revisited for better assessment of the impact of impervious cover on the long-term runoff process.

• 한국수자원학회논문집
• /
• 제53권12호
• /
• pp.1173-1181
• /
• 2020

최근 단기간의 국지성호우가 빈번하게 발생하면서 단순 1차적 피해를 넘어 경제적, 사회적 영향이 커지고 있다. 기상선진국에서는 단순 기상예보로서의 정보전달이 아닌 사회 경제적 영향을 분석하여 현실적이고 신뢰할 수 있는 영향예보를 실시하고 있다. 본 논문에서는 사람의 보행에 영향을 미칠 수 있는 영향한계강우량을 산정하기 위해서 Spatial Runoff Assessment Tool (S-RAT), FLO-2D 모델을 사용하여 침수정도를 도출하였고 Grid to Grid (G2G)개념의 한계강우량을 산정하였다. 또한, 과거 의학 분야에서 많이 사용하였지만 현재는 가뭄이나 홍수 등의 자연현상 및 머신러닝에 많이 사용하는 ROC 분석 기법을 통해 정량적인 정확도분석을 실시하였다. 분석 결과 실제 침수와 모의 침수가 비슷한 시간대의 결과가 나왔으며 ROC 곡선의 결과 0.7이상으로 Fair 단계의 적정성을 확보하였다.

• 한국환경보건학회지
• /
• 제34권3호
• /
• pp.247-254
• /
• 2008

Non-point source pollution that originates from surface applied chemicals in either liquid or solid form is a part of urban activities and it appears in the surface runoff caused by rainfall. This study investigates the characteristics of non point source pollution in relation to storm events and the first washing effect in the Study area, which is comprised of different land use types. Then, a Best Management Practices (BMP) model, for urban areas, is applied with the Storm water Management Model (SWMM) Windows Interface which was developed by the EPA in the USA. During the storm event analysis of the hydrographic and pollutographic data showed that the peak of pollutants concentration was within the peak flow, 30 to 60 minute into the storm event in the Study area. The results of simulation using SWMM Windows Interface, Structure Techniques as applied in the study were highly efficient for removal of pollutants. Predicted removal efficiency was 26.0% for SS, 22.1 for BOD, 24.1% for COD, 20.6% for T-N, and 21.6% for T-P, respectively.

• 환경영향평가
• /
• 제15권2호
• /
• pp.157-163
• /
• 2006

The purpose of this study is to understand imperviousness impact for the characteristics of stormwater runoff and water temperature. The land-use map was used to estimate the watershed imperviousness(percent of impermeable area) and the RMS(Remote Monitoring System) was used to evaluate the stormwater runoff of watershed. This study was investigated for two streams(Jiam and Gongji) in Chunchon City. The detailed results of these studies are as follows; The imperviousness(%) of two watersheds(Jiam and Gongji) estimated by spatial analysis which is main function of GIS were 0.24% and 24.16%. So, Gongji watershed as urban area was about 100 times than jiam watershed as forest area. In case of rainfall of low intensity, stormwater runoff flowrate in higher imperviousness area(Gongji) was more than it in forest area(jiam). Also, The time to peak flowrate(Tp) was short in Gongji stream and the water temperature difference between Gongji and Jiam stream was about $4.4^{\circ}C$ in summer.

• 물과 미래
• /
• 제26권4호
• /
• pp.85-95
• /
• 1993

본 연구의 목적은 도시소유역에서의 부족한 유량 및 NPS 오염물 자료의 확충과 이를 통한 유출과 NPS 오염물 배출 간의 상관관계의 분석 및 월, 년 NPS 부하량 산정에 의한 물질수지의 분석에 있다. 본 연구를 위한 자료의 확충을 위해서 미국 EPA의 SWMM 모형을 사용하였으며, 상관관계의 분석 및 물질수지의 분석은 NPS 오염에 가장 영향이 큰 선행괘천기간을 긴 경우(CASE 1.)와 짧은 경우(CASE 2.)로 분리하여 수행하였으며, 연구 결과를 요약하면 다음과 같다. 1) 사상별 시간자료의 분석 : CASE 1.과 CASE 2. 모두, 유량과 농도간의 상관관계 보다는 유량과 부하량간의 상관관계가 좋았으며, 선형 상관관계보다는 비선형 상관관계가 좋았다. 결과적으로 두 CASE 모두 비유량-비부하율 관계는 비선형 산관관계가 가장 좋았다. 2) 사상별 총량자료의 분석 : CASE 1.은 비누적유량-비누적부하량의 선형상관관계가 CASE 2.는 비선형 상관관계가 좋았다. 3) 유역의 NPS 년비부하량 산정 결과, 년평균 단위 강우량당 비부하량은 CASE 1.이 CASE 2.보다 모든 오염물에서 약 2.5배였다. 4) 호우기와 갈수기의 NPS 오염물의 비교 결과, 갈수기의 CASE 1.의 비중이 훨씬 컸다. 5) NPS 년비부하량과 PS 년비부하량을 비교한 결과, NPS 오염물이 유역 및 하천의 오염에 상당히 기여함을 알 수 있었다.