• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.288-288
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• 2019

지구온난화로 인해 해수면이 지속적으로 상승하고 있으며, 이에 따라 연안인근 지역은 복합원인에 의한 홍수피해가 빈번히 발생하고 있다. 우리나라는 반도 지형으로 해수면 상승에 따라 침수피해 발생 시 피해규모가 클 것으로 예상되어 이에 적극적으로 대처할 필요가 있다. 복합원인에 의한 침수예상도는 해수위를 고려한 내외수 침수피해 발생 시 침수의 범위 및 양상을 예측한다. 먼저 침수발생 시 피해규모가 클 것으로 예상되는 연안인근의 도심지역을 위주로 대상지역을 선정하였으며, 침수발생 원인별 침수예상도를 작성하였다. 작성된 침수예상도를 바탕으로 상세 홍수취약성을 평가하였으며, 이를 바탕으로 주요 시설물의 위치 선정, 관거 개량의 우선순위 선정 등에 활용할 수 있다. 먼저 도상조사를 통해 침수발생 후보지역을 선정하고, 현장답사를 통해 현장 변경사항, 재해원인 및 재해발생가능성을 검토하여 대상지역으로 여수시 연등천 인근을 선정하였다. 모의 방법으로는 HEC-HMS 및 XP-SWMM 등 강우-유출 모형에 의해 침수해석을 실시하고, 하류단 경계조건의 변화에 따른 기점수위를 산정하여 해수위를 고려하였다. 하류단 경계조건으로는 대상지역의 폭풍해일에 의한 해수위 상승고를 적용하였다. 배수토구가 하천으로 연결된 경우에는 해당 하천의 홍수위 산정이 필요하며 홍수위 산정에는 HEC-RAS 모형을 사용하였다. 작성된 침수예상도를 통해 상세 홍수취약성 분석을 실시하였으며, 상세 홍수취약성 지수는 "기후변화 적응을 위한 연안도시지역별 복합원인의 홍수 취약성 평가기술 개발 및 대응방안 연구"에서 개발된 지표를 기반으로 산정하였다. 본 연구에서는 강우-유출 모형의 하류단 경계조건 변화를 통해 해수위 상승을 고려하여 연안도시 지역의 침수예상도를 작성하였으며, 침수발생 예상도를 통해 상세 홍수취약성을 분석하였다. 이는 침수발생에 따른 대피지도 개발, 주요 시설물의 계획, 침수피해 예방을 위한 구조적 대책 수립을 위한 기초자료로 활용될 수 있다.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.497-497
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• 2022

홍수위험지도는 홍수발생시 예방되는 침수범위와 침수깊이를 나타내는 지도로 2009년 영산강수계(237.53 km), 2016년에 섬진강수계(251.06 km) 국가하천의 홍수위험지도가 제작되었고, 2021년 영산·섬진강권역 지방하천(4521.31 km) 홍수위험지도가 제작됨으로써 영산·섬진강권역 홍수위험지도 제작이 모두 완료되었다. 홍수위험지도 제작은 GIS 범람해석, 1차원 및 2차원 수치모형으로 구분할 수 있따. GIS 범람해석은 제내지의 지형 수치표고모델(DEM) 등을 활용하여 지형자료를 구축하고, 측점별 홍수위를 이용한 홍수위 DEM을 작성한 후 각 DEM의 고도차를 계산하여 홍수범람구역을 도시하는 방법이다. 도심지 또는 주거지를 관류하는 하천에 대해서는 제방의 편안 파제를 가정하여 FLUMEN모형을 이용한 2차원 범람분석 또는 HEC-RAS모형을 이용한 1차원 범람분석 방법 적용한다. 위와 같은 분석 방법으로 도출된 침수 결과는 제방 월류 및 제방 유실 등의 극한 상황을 가정한 것으로, 2020년 섬진강 대홍수 홍수피해 침수구역과 홍수위험지도의 침수구역의 겨의 일치하는 것으로 나타났다. 즉 하천홍수로 발생할 수 있는 피해의 규모를 예측할 수 있으며, 이러한 예측정보는 방재계획 수립 및 홍수대응에 활용도가 높을 것이다. 홍수위험지도는 홍수위험지도정보시스템(www.floodmap.go.kr)에서 누구나 확인이 가능하며, 지자체 방재담당자는 회원가입을 통해 홍수위험지도 전산파일 및 보고서 등을 받을 수 있다. 방재담당자는 홍수위험지도의 침수구역을 바탕으로 대피계획을 수립하고, 집중호우로 인한 하천수위 상승 시 홍수위험지도의 침수구역을 중심으로 방재활동을 하여 인명피해를 최소화할 수 있을 것이다.

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.5
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• pp.506-513
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• 2020

Due to climate change, there is an increasing risk of complex (hybrid) disasters, comprising rising sea-levels, typhoons, and torrential rains. This study focuses on Marine City, Busan, a new residential city built on a former landfill site in Suyeong Bay, which recently suffered massive flood damage following a combination of typhoons, storm surges, and wave overtopping and run-up. Preparations for similar complex disasters in future will depend on risk impact assessment and prioritization to establish appropriate countermeasures. A framework was first developed for this study, followed by the collection of data on flood prediction and socioeconomic risk factors. Five socioeconomic risk factors were identified: (1) population density, (2) basement accommodation, (3) building density and design, (4) design of sidewalks, and (5) design of roads. For each factor, absolute criteria were determined with which to assess their level of risk, while expert surveys were consulted to weight each factor. The results were classified into four levels and the risk level was calculated according to the sea-level rise predictions for the year 2100 and a 100-year return period for storm surge and rainfall: Attention 43 %, Caution 24 %, Alert 21 %, and Danger 11 %. Finally, each level, indicated by a different color, was depicted on a complex disaster risk map.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.21 no.3
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• pp.269-275
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• 2003

The cadastral system which accomplishes the base of national land administration with accuracy of proper data and the cadastral maintenance quickly is agreeing with the actual place in information ages in Inundation. But even in spite of many efforts, various Problems are exposed in accuracy of the data on the cadastral maps and local situation must agree accurately from the process which propels cadastral information systems. Therefore, it must be carried out the cadastral non correspondence arrangement first of all in link of the plan which it corrects the error of existing data and computerization quickly. It summarizes the research as follows ; Cadastral non correspondence of the land boundaries on the map and actual circumstance does not agree with cadastral maps accurately, The lands which exceed the standards with the position error excess of 50cm on lil ,200 and 240cm on 1/6,000 areas on the map scale are the registration correction objectives. It is investigated that the cadastral non correspondence parcels occur in various cause and long period, the area error corrections are mainly objectives, and about 80% of the test area comes to reveal within permitted the limit of the measurement of planimetric area for cadastral survey, so it is not difficult with the fact that the compensation back which it follows in area increase and decrease and the location error correction becomes the important object fer the cadastral non correspondence arrangement projects.

• Journal of Korean Society for Geospatial Information Science
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• v.14 no.1 s.35
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• pp.49-55
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• 2006

Nowadays, flood hazard maps have been generated to minimize the damages from the flooding. To generate such flood hazard maps, LiDAR data can be used as data source with higher data accuracy. LiDAR data, however, requires relatively higher cost and longer processing time. In this background, this study proposed DEM generation using NGIS digital topographic maps. For that, breaklines were processed to count directions of water flows. In addition, the river profile data, unique data source to represent real topography of the river area, were integrated to the breaklines to generate DEM. City of Kuri in Kyunggi Province was selected for this study and 1:1,000 and 1:5,000 topographic maps were integrated to process breaklines and river profile data were also linked to generate DEM. The generated DEM showed relatively lower vertical accuracy from mixing 1:1,000 and 1:5,000 topographic maps since 1:1,000 topographic maps were not available for some portion of the area. However, the DEM generated demonstrated reasonable accuracy and resolution for flood map generation as well as higher cost saving effects. On the contrary, for more efficient utilization of NGIS topographic maps, periodic map updating needs to be made including technical consideration in building breaklines and applying interpolation methods.

• Journal of Korea Water Resources Association
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• v.52 no.5
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• pp.361-372
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• 2019

The purpose of this study is to develop a two-dimensional land surface flood analysis model based on uniform square grid using the governing equations except for the convective acceleration term in the momentum equation. Finite volume method and implicit method were applied to spatial and temporal discretization. In order to reduce the execution time of the model, parallel computation techniques using CPU were applied. To verify the developed model, the model was compared with the analytical solution and the behavior of the model was evaluated through numerical experiments in the virtual domain. In addition, inundation analyzes were performed at different spatial resolutions for the domestic Janghowon area and the Sebou river area in Morocco, and the results were compared with the analysis results using the CAESER-LISFLOOD (CLF) model. In model verification, simulation results were well matched with the analytical solution, and the flow analyses in the virtual domain were also evaluated to be reasonable. The results of inundation simulations in the Janghowon and the Sebou river area by this study and CLF model were similar with each other and for Janghowon area, the simulation result was also similar to the flooding area of flood hazard map. The different parts in the simulation results of this study and the CLF model were compared and evaluated for each case. The results of this study suggest that the model proposed in this study can simulate the flooding well in the floodplain. However, in case of flood analysis using the model presented in this study, the characteristics and limitations of the model by domain composition method, governing equation and numerical method should be fully considered.

• Journal of Korea Water Resources Association
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• v.49 no.6
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• pp.519-528
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• 2016

Frequently torrential rain is occurred by climate change and urbanization. Urban is formed with road, residential and underground area. Without detailed topographic flooded analysis consideration can take a result which are wrong flooded depth and flooded area. Especially, flood analysis error of population and assets in dense downtown is causing a big problem for establishments and disaster response of flood measures. It can lead to casualties and property damage. Urban flood analysis is divided into sewer flow analysis and surface inundation analysis. Accuracy is very important point of these analysis. In this study, to confirm the effects of the elevation data precision in the process of flooded analysis were studied using 10m DEM, LiDAR data and 1:1,000 digital map. Study area is Dorim-stream basin in the Darim drainage basin, Sinrim 3 drainage basin, Sinrim 4 drainage basin. Flooding simulation through 2010's heavy rain by using XP-SWMM. Result, from 10m DEM, shows wrong flood depth which is more than 1m. In particular, some of the overflow manhole is not seen occurrence. Accordingly, detailed surface data is very important factor and it should be very careful when using the 10m DEM.

• Journal of Environmental Science International
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• v.14 no.9
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• pp.817-825
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• 2005

The purpose of this study was to research about salt marsh flora and vegetation in the Dongjin-river estuary area where has a project for Sea Man Geum Reclaimed Land so that we can foster foundation on restoration of an ecological habitat, development of applicable plant and establishment of a conservation policy after deceloping the reclaimed land for salt marsh vegetation which has great value ecologically. In conclusion, we was distributed that there are 7 families 21 genera, 25 species, 2 varieties of vascular plant at the Dongjin-river estuary area which have 27 taxa in total and are $0.64\%$ among 4,191 of korean vascular plant. There are also 2 family, 2 genus, 2 species of a naturalized plant which are $1.1\%$ of indicator of a naturalized plant salt marsh vegetation of the downstream are very much affected by the time of inundation, tidal water so that a low degree of salt marsh has frequent flooding by sea water and has a pure group of Suaeda japonica. A Phragmites communis, Carex scabrifolia are distributed mainly around a waterway of salt marsh and Zoysia sinica, Atriplex subcordata, Phragmites communis are living in stock as forming into patch around medium salt marsh. Suaeda asparagoides, Phacelurus latifolius are living around a little high ground and a Phragmites communis is a behind vegetation of Phacelurus latifolius and a part of the Phragmites communis are living along with waterway in a salt marsh as a community. By the 2-M method twelve plant communities were recognized ; Suaeda japonica. Carex scabrifolia, Zoysia sinica, Artemisia scoparia, Phacelurus latifolius, Phragmites communis, Suaeda maritima, Suaeda japonica-Atriplex gmelini, Phragmites communis-Suaeda japonica, Suaeda japonica-Salicornia herbacea, Salicornia herbacea-Suaeda aspar-agoides and Scirpus planiculmis community. The actual vegetation map was constructed on the grounds of the communities classified and other data.

• Journal of Korean Society of Disaster and Security
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• v.13 no.2
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• pp.53-63
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• 2020

In this study, the two-dimensional flow analysis model Hydro_AS-2D model was used to simulate the situation of flooding in Seongsangu and Uichang-gu in Changwon in the event of rising sea levels and extreme flooding, and the results were expressed on three-dimensional topography and the optimal evacuation path was derived using BIM technology. Climate change significantly affects two factors in terms of flood damage: rising sea levels and increasing extreme rainfall ideas. The rise in sea level itself can not only have the effect of flooding coastal areas and causing flooding, but it also raises the base flood level of the stream, causing the rise of the flood level throughout the stream. In this study, the rise of sea level by climate change, the rise of sea level by storm tidal wave by typhoon, and the extreme rainfall by typhoon were set as simulated conditions. The three-dimensional spatial information of the entire basin was constructed using the information of topographical space in Changwon and the information of the river crossing in the basic plan for river refurbishment. Using BIM technology, the target area was constructed as a three-dimensional urban information model that had information such as the building's height and location of the shelter on top of the three-dimensional topographical information, and the results of the numerical model were expressed on this model and used for analysis for evacuation planning. In the event of flooding, the escape route is determined by an algorithm that sets the path to the shelter according to changes in the inundation range over time, and the set path is expressed on intuitive three-dimensional spatial information and provided to the user.

• The Journal of Engineering Geology
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• v.24 no.4
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• pp.501-510
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• 2014

Volcanic eruptions alone may lead to serious natural disasters, but the associated release of water from a caldera lake may be equally damaging. There is both historical and geological evidence of the past eruptions of Mt. Baekdusan, and the volcano, which has not erupted for over 100 years, has recently shown signs of reawakening. Action is required if we are to limit the social, political, cultural, and economic damage of any future eruption. This study aims to identify the area that would be inundated following a volcanic flood from the Cheon-Ji caldera lake that lies within Mt. Baekdusan. A scenario-based numerical analysis was performed to generate a flood hydrograph, and the parameters required were selected following a consideration of historical records from other volcanoes. The amount of water at the outer rim as a function of time was used as an upper boundary condition for the downstream routing process for a period of 10 days. Data from the USGS were used to generate a DEM with a resolution of 100 m, and remotely sensed satellite data from the moderate-resolution imaging spectroradiometer (MODIS) were used to show land cover and use. The simulation was generated using the software FLO-2D and was superposed on the remotely sensed map. The results show that the inundation area would cover about 80% of the urban area near Erdaobaihezhen assuming a 10 m/hr collapse rate, and 98% of the area would be flooded assuming a 100 m/hr collapse rate.