• 환경정책연구
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• 제7권3호
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• pp.121-140
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• 2008

불투수면 비율은 유역의 건전성 정도를 나타내는 중요한 척도로 활용되고 있으며 특히 유역의 수환경 특성을 파악하는 모델에서 이용되어 왔다. 불투수면은 총불투수면과 유효불투수면의 두 가지 있으며, 이들은 각 유역의 토지이용 특성에 따라 그 구성이 다양하다. 이중 총 불투수면은 기존의 토지이용도나 토지피복도를 사용하여 손쉽게 구할 수 있는 반면 유효불투수면은 물 흐름을 필지별로 파악하여야 하기 때문에 산정에 많은 노력과 비용이 소요된다. 본 연구에서는 우리나라 사례지역에 대해 총불투수면과 유효불투수면을 산정하여 그 특성을 상호 비교해 보고 유역관리에 있어 유효 및 총 불투수면 비율의 적용방안을 모색하고자 하였다. 사례지역 분석결과 유효불투수면 면적은 39.7%로 총 불투수면 면적 43%에 비해 약 3%적었다. 불투수면이 수환경에 미치는 영향을 분석하기 위한 기초 자료로 활용하기 위함임을 고려할 때 비용과 시간적 측면에서 볼 때 총불투수면을 유역의 대표적인 불투수면 비율로 사용할 수 있을 것으로 판단된다.

• 상하수도학회지
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• 제23권2호
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• pp.181-187
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• 2009

In this study, a runoff hydrograph and runoff volume were calculated by using the kinetic wave theory for small urban watersheds based on the concept of low impact development(LID), and the effective imperviousness was estimated based on these calculations. The degree of sensitivity of the effective imperviousness of small watersheds to the impervious to pervious area ratio, infiltration capability, watershed slope, roughness coefficient and surface storage depth was then analyzed. From this analysis, the following conclusions were obtained: The effective imperviousness and paved area reduction factor decreased as the infiltration capability of pervious area increased. As the slope of watersheds becomes sharper, the effective imperviousness and the paved area reduction factor display an increasing trend. As the roughness coefficient of impervious areas increases, the effective imperviousness and the paved area reduction factor tend to increase. As the storage depth increases, the effective imperviousness and the paved area reduction factor show an upward trend, but the increase is minimal. Under the conditions of this study, it was found that the effective imperviousness is most sensitive to watershed slope, followed by infiltration capability and roughness coefficient, which affect the sensitivity of the effective imperviousness at a similar level, and the storage depth was found to have little influence on the effective imperviousness.

• 한국환경과학회지
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• 제24권10호
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• pp.1239-1251
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• 2015

Impervious areas have been expanded by urbanization and the natural structure of water circulation has been destroyed. The limits of centralized management for controlling storm water runoff in urban areas have been suggested. Low impact development (LID) technologies have been promoted as a crucial alternative, establishing a connection with city development plans to build green infrastructures in environmentally friendly cities. Thus, the improvement of water circulation and the control of nonpoint source were simulated through XP-SWMM (storm water and wastewater management model for experts) in this study. The application of multiple LID combination practices with permeable pavements, bioretention cells, and gutter filters were observed as reducing the highest runoff volume by up to 70%. The results from four different LID installation scenarios indicated that permeable paving is the most effective method for reducing storm water runoff. The rate of storm water runoff volume reduced as the rainfall duration extended. Based on the simulation results, each LID facility was designed and constructed in the target area. The LID practices in an urban area enable future studies of the analysis of the criteria, suitable capacity, and cost-efficiency, and proper management methods of various LID techniques.

• 상하수도학회지
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• 제24권6호
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• pp.691-701
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• 2010

As the water-cycle is transformed by increasing of the impermeable area in process of urbanization, decentralized rainwater management facilities(infiltration, harvesting and retention facilities) as source control are considered to be a method of restoring water-cycle of urban and reducing runoff. SWMM model was used to analyse the change of water-cycle structure before and after development in A new town watershed. Modified SWMM code was developed to apply infiltration facilities. The modified SWMM was used to analyse the change of water-cycle before and after infiltration trench setup in AJ subcatchment. Changes of the impervious area by development and consequent increase in runoff were analyzed. These analyses were performed by a day rainfall during ten years from 1998 to 2007. According to the results, surface runoff increased from 51.85% to 65.25 %, and total infiltration volume decreased from 34.15 % to 21.08 % in A newtown watershed. If more than 80 infiltration trenches are constructed in AJ subcatchment, the low flow and the drought flow increases by around 47%, 44%, separately. The results of this study, infiltration trench is interpreted to be an effective infiltration facility to restore water-cycle in new town.

• 농촌계획
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• 제21권3호
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• pp.101-112
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• 2015

The objective of this study was to investigate non-point sources (NPS) pollution and prioritize management areas affected by NPS pollution in the Saemangeum Watershed. AHP (Analytical Hierarchy Process) technique was selected to prioritize sub-watersheds for effectively managing NPS pollution in this study areas. Generation properties of NPS pollution, discharge properties of NPS pollution, and runoff properties of NPS pollution were selected and set for AHP. Weighted descriptors including indicators like numbers of livestock, land- and livestock-system loads, rainfall, and impervious area ratio were generalized from 0 to 1 and multiply each index based on screened 17 survey data. The results were visualized as maps which enable resource managers to identify sub-watersheds for effective improving water quality. The sub-watersheds located in Gongdeok-Myeon, Yongji-Myeon, Hwangsan-Myeon of Gimje-Si were selected for managing NPS pollution control areas. This result presented that these sub-watershed are more affected by the pollution from livestock-system than from land-system. The finding from this study can be used to screen sub-watersheds that need further assessment by managers and decision-makers within the study area.

• 한국습지학회지
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• 제14권2호
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• pp.159-168
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• 2012

도시화된 토지이용은 불투수율이 높고 강우시 다량의 비점오염물질이 유출되어 지표수 및 지하수에 영향을 끼친다. 이러한 포장지역의 비점오염물질로 인한 수질오염을 저감하기 위하여 환경부는 수질오염총량제도 및 개발사업에 대한 비점오염 저감시설 설치신고 제도를 도입하여 운영 중에 있다. 그러나 비점오염저감시설의 규모 및 저감기능 설계를 위해서는 유출특성 분석이 필요하나 현재 기초자료가 부족하여 원단위 산정 등의 애로점으로 남아있다. 따라서 본 연구에서는 원단위 산정 및 저감시설의 규모산정에 필요한 강우유출수 특성과 EMC를 제시하고자 한다. 모니터링은 도로 및 주차장에서 3년간 총 30개의 강우사상에 대하여 수행되었다. 초기강우 유출현상은 강우 시작 후 30분 동안 매우 분명하게 나타났으며, 유출수의 농도에 영향을 미치는 인자는 강우량, 유역면적, 토지이용, 지리 및 지형적 특성으로 분석되었다. 본 연구결과는 향후 포장지역의 원단위 산정 및 저감시설 설계시 기초자료로써 활용가능할 것으로 판단된다.

• 환경영향평가
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• 제23권1호
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• pp.39-50
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• 2014

In recent years, the frequency and scale of the natural disasters are growing rapidly due to the global climate change. In case of the urban flooding, high-density of population and infrastructure has caused the more intensive damages. In this study, we analyzed the spatial characteristics of urban flooding damage factors using GWR(Geographically Weighted Regression) for effective disaster prevention and then, classified the causes of the flood damage by spatial characteristics. The damage factors applied consists of natural variables such as the poor drainage area, the distance from the river, elevation and slope, and anthropogenic variables such as the impervious surface area, urbanized area, and infrastructure area, which are selected by literature review. This study carried out the comparative analysis between OLS(Ordinary Least Square) and GWR model for identifying spatial non-stationarity and spatial autocorrelation, and in the results, GWR model has higher explanation power than OLS model. As a result, it appears that there are some differences between each of the flood damage areas depending on the variables. We conclude that the establishment of disaster prevention plan for urban flooding area should reflect the spatial characteristics of the damaged areas. This study provides an improved understandings of the causes of urban flood damages, which can be diverse according to their own spatial characteristics.

• 한국물환경학회지
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• 제35권1호
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• pp.35-42
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• 2019

Urbanization has led to extreme changes in land use on urban watersheds. Most cities are becoming residential, commercial and industrial areas, making infiltration and storage of rainfall less favorable. The demand for LID (Low Impact Development) technology is increasing in order to mitigate this water cycle distortion and return to existing hydrological conditions. The LID technique is effective in reducing runoff by permeating the urban impervious area. However, considering the limit of the installation area and the financial requirement of the installation, there is not much research on the linkage of each LID component technology for optimum efficiency according to the appropriate scale. In this study, the effects of the LID facilities applied to the target site were simulated using the SWMM model, suggesting the optimal linkage method considering interconnectivity, and applying the effects as an existing installation of individual facilities. The water balance at the time of application of the LID technology, short-term and long-term rainfall event were compared. Also, the individual application and the linkage application were compared with each other. If each component technology has sufficient processing size, then linkage application is more effective than individual application.

• 한국측량학회지
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• 제39권2호
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• pp.113-122
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• 2021

Urban expansion, particularly converting sub-urban areas to residential and commercial land use in metropolitan areas, has been considered as a significant signal of regional economic development. However, this results in urban climate change. One of the key impacts of rapid urbanization on the environment is the effect of UHI (Urban Heat Island). Understanding the effects of urban land cover change on UHI is crucial for improving the ecology and sustainability of cities. This research reports an application of remote sensing data, GIS (Geographic Information Systems) for assessing effects of urban land cover change on the LST (Land Surface Temperature) and heat budget components in Ho Chi Minh City, where is one of the fastest urbanizing region of Vietnam. The change of urban land cover component and LST in the city was derived by using multi-temporal Landsat data for the period of 1998 - 2020. The analysis showed that, from 1998 to 2020 the city had been drastically urbanized into multiple directions, with the urban areas increasing from approximately 125.281 km² in 1998 to 162.6 km² in 2007, and 267.2 km² in 2020, respectively. The results of retrieved LST revealed the radiant temperature for 1998 ranging from 20.2℃ to 31.2℃, while that for 2020 remarkably higher ranging from 22.1℃ to 42.3℃. The results also revealed that given the same percentage of urban land cover components, vegetation area is more effective to reduce the value of LST, meanwhile the impervious surface is the most effective factor to increase the value of the LST.

• 한국수자원학회논문집
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• 제47권6호
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• pp.513-522
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• 2014

최근 도시화 및 기후변화에 의한 홍수피해의 증가로 인하여 이에 대응하는 방안으로 저영향개발(LID) 요소기술에 관하여 다양하게 개발이 되고 있다. 하지만 이러한 요소기술에 대한 효율을 검증할 수 있는 표준화된 검증방법 및 기기는 부재한 실정이다. 본 연구에서는 LID 기법에 대한 물순환의 효율성 검증이 가능한 강우-유출 모의장치를 개발하였다. 소유역 내 강우가 균등하게 분사될 수 있도록 강우공간분포실험 및 유입유량-유효우량 관계 실험을 통하여 강우를 검증하고 유입되는 강우와 이로 인해 발생되는 침투 및 지표유출 관계 실험을 실시하였다. 그 결과 노즐의 종류에 따른 적정유량범위와 RPM의 관계를 정리하였으며 강우-유출 모의장치를 이용한 실험을 통해 투수면과 불투수면에서의 강우 시의 수문학적 물순환(지표유출, 중간유출, 침투량)의 관계를 정량적으로 검증하였다.