Flood Hazard Mapping and Vulnerability Analysis of Bishnumati River, Nepal

Flood is one of the striking water induced disaster that hits most of the part of the world. In Nepal also it is one of the serious disasters which affect the human lives and huge amount of property. The increase of population and squatter settlements of landless people living at the bank of the river has tremendous pressure in encroachment of flood plain making them vulnerable to the flood damage. The study describes the technical approach of probable flood vulnerability and flood hazard analysis. Bishnumati catchment was taken as area of study. One dimension model of HEC-RAS with HEC-GeoRAS interface in co-ordination with ArcGIS was applied for the analysis. Analysis shows that the flood area increases with flood intensity. Higher flood depth increases and lower flood depth decreases with increase in intensity of flood. Inundation of huge area of urban land indicates that in future human lives are more prone to flood disaster. Thus, the study may help in future planning and management for future probable disaster.Nepalese Journal on Geoinformatics, Vol. 14, 2015, page: 20-24

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Use of Geo-Informatics in Flood Hazard Mapping: A Case of Balkhu River

Journal on Geoinformatics, Nepal ◽

10.3126/njg.v13i0.16937 ◽

2017 ◽

Vol 13 ◽

pp. 52-57

Author(s):

Susheel Dangol

Keyword(s):

Flood Hazard ◽

Hazard Analysis ◽

System Model ◽

One Dimension ◽

Hazard Mapping ◽

Land Area ◽

Technical Approach ◽

Barren Land ◽

Flood Depth ◽

Analysis System

Flood is one of the striking water induced disaster that hits most of the part of the world. In Nepal also it is one of the serious disasters which affect the study describes the technical approach of probable flood hazard analysis. Segment of Balkhu River within the Balkhu catchment of area 44.37 km2 from Kirtipur gorge to Bagmati confluence was taken as area of study. The total length of the study segment was 5485.89 m. One dimension HEC-RAS (Hydrologic Engineering Center-River Analysis System) model was used for the analysis. The study shows that higher flood depth increases and low flood depth decreases with increase in intensity of flood. Also, huge area of barren land area is affected by flood and few percentage of settlement area is affected by flood indicating the damages to the human lives. Huge area of barren land indicates that in future human lives are more prone to disasters as those lands have gone through planning for future settlement.Nepalese Journal on Geoinformatics -13, 2014, Page: 52-57

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Flood hazard assessment of a flood-prone intensively urbanized area – A case study from Samsun Province, Turkey

Geofizika ◽

10.15233/gfz.2020.37.2 ◽

2020 ◽

Vol 37 (1) ◽

pp. 1-25

Author(s):

Neslihan Beden ◽

Aslı Ülke Keskin

Keyword(s):

Flood Hazard ◽

Wide Spectrum ◽

Flood Plain ◽

Flood Management ◽

Flood Damage ◽

The Black Sea ◽

Hazard Maps ◽

Flood Depth ◽

The Social ◽

Flood Hazard Maps

Flooding is one of the most catastrophic events among the wide spectrum of natural disasters that impact human communities. The identification of floodprone areas and the probability of occurrence, or estimated return period, of flood events are fundamental to proper planning for flood management and minimization of the social and economic costs of flood damage. In this study, 1D/2D coupled flood models of the Mert River, which flows into the Black Sea at Samsun in north-central Turkey, were developed. Based on the flood modeling results, flood extent, flood depth and flood hazard maps for the river were produced and they showed that the study area is particularly flood prone, as evidenced by catastrophic flooding in 2012. Specifically, the estimated 100, 500 and 1000-year peak discharges would affect 184 ha, 262 ha and 304 ha, respectively, of the 1,200 ha study area. Hazard ratings for the areas expected to be affected are shown in the flood hazard maps generated. The results of this research can be used by local government agencies in Samsun for the development of policies, strategies and actions that would help minimize the social and economic impacts of flooding, especially adjacent to the downstream sections where there is intensive development on the flood plain.

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An approach for flood hazard modelling and mapping in the medium Valtellina

Natural Hazards and Earth System Science ◽

10.5194/nhess-11-1141-2011 ◽

2011 ◽

Vol 11 (4) ◽

pp. 1141-1151 ◽

Cited By ~ 11

Author(s):

I. Poretti ◽

M. De Amicis

Keyword(s):

Urban Planning ◽

Flood Hazard ◽

Hazard Analysis ◽

Hazard Mapping ◽

Hazard Maps ◽

Experimental Modelling ◽

Hydrodynamic Simulations ◽

Lombardy Region ◽

Legislative Framework ◽

Modelling Approach

Abstract. In the Lombardy Region, as in many other contexts all over the world, hazard maps do not have a precise legislative confirmation. Despite this, they are necessary to support several institutional activities, and among these, local urban planning. An approach to hazard analysis and mapping that fits the Lombardy Region legislative framework is presented here that introduces a level of experimental modelling, making use of SOBEK 1-D–2-D as a tool for hydrodynamic simulations. A stretch of 17 km of the Adda river in Valtellina has been modelled, referring to twelve scenarios characterised by different temporal probabilities, and comprising the main sources of uncertainty. The results were compared with available local hydraulic studies, and combined to obtain two complementary flood hazard maps which could usefully support urban planning. Advantages and drawbacks of this modelling approach, together with considerations related to flood hazard mapping are discussed.

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A Study on Squatter Settlements of Kathmandu Using GIS, Aerial Photography, Remote Sensing and Household Survey

Journal on Geoinformatics, Nepal ◽

10.3126/njg.v10i0.23186 ◽

2011 ◽

Vol 10 ◽

pp. 1-8

Author(s):

Kiran K.C. ◽

Krishna Pahari

Keyword(s):

Flood Hazard ◽

Household Survey ◽

Flood Plain ◽

Hazard Mapping ◽

Kathmandu Valley ◽

High Concentration ◽

Squatter Settlements ◽

Clear Cut ◽

Hilly Region ◽

Hygienic Conditions

The study was done to explore various issues facing by the squat dwellers of two densely populated squatter settlements of the Kathmandu valley (Manohara and Thapathali). A series of temporal satellite imageries along with orthophoto were analyzed and mapped focusing the food security and their livelihood conditions, sanitary and hygienic conditions and the flood hazard assessment. The study revealed that there has been a drastic landuse change in the Manohara area as compared to the Thapathali one. The squatter settlement that currently exists is found to have been in the flood plain. The household survey has disclosed that a majority of squatters who have settled in these places belong to Janajatis and they have mainly migrated from the hilly region and the surrounding districts of the Kathmandu valley. Besides, drinking water tested from both of the areas is contaminated with high concentration of Nitrate and Coliform. Hygienic conditions are also very poor as toilets lie along the river banks resulting in the depletion of the river quality and the scenic beauty of the surrounding environment. The community-based flood hazard mapping done with the GPS survey has revealed that all the settlements from both of the areas had been inundated in the month of July in 2009. In both area, people are deprived of basis amenities and they have been neglected by the concerned government authorities. Adequate research on scientific basic is an urgent need so as to draft a clear cut specific policy that can address their issues and stop environmental deterioration, destruction of beautiful green grassland and the sanitary conditions.

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A Flood Damage and Shelter Need Assessment: A Case Study of Mueang Sing Buri, Thailand

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/884/1/012025 ◽

2021 ◽

Vol 884 (1) ◽

pp. 012025

Author(s):

Pattaramone Manawongcharoen ◽

Thitirat Panbamrungkij

Keyword(s):

Flood Hazard ◽

Relevant Information ◽

Flood Damage ◽

Hazard Map ◽

Risk Map ◽

Hazard Management ◽

Flood Depth ◽

Chao Phraya River ◽

Flood Risk Map

Abstract Flooding is one of the main disasters in Thailand and Mueang Sing Buri is among those areas hit. Located on the Chao Phraya River Basin, in the central region of Thailand, the area receives a large amount of runoff during monsoon seasons which causes frequent flood disasters. The aims of this research are to create a flood hazard map and to estimate the number of people that may need shelter after the occurrence of a flood, and to evaluate whether the shelter capacity is adequate in Mueang Sing Buri. To explore the potential locations of emergency shelters, the relevant information related to flooding was initially recorded, such as building detail, flood depth, elevation map, and flood risk map. The available space of each building varies by the characteristics of building types. The calculation of shelter capacity thus depends on characteristics of the buildings, accessibility, and percent of vacant area. The emergency shelter assessment benefits many sectors in the design of preparation plans for hazard management.

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Flood Hazard Zonation Using an Artificial Neural Network Model: A Case Study of Kabul River Basin, Pakistan

Sustainability ◽

10.3390/su132413953 ◽

2021 ◽

Vol 13 (24) ◽

pp. 13953

Author(s):

Muhammad Saeed ◽

Huan Li ◽

Sami Ullah ◽

Atta-ur Rahman ◽

Amjad Ali ◽

...

Keyword(s):

Neural Network ◽

River Discharge ◽

Flood Hazard ◽

Soil Surface ◽

Hazard Mapping ◽

Drainage Network ◽

Flood Depth ◽

Slope Flow ◽

Surface Geology ◽

Kabul River

Floods are the most frequent and destructive natural disasters causing damages to human lives and their properties every year around the world. Pakistan in general and the Peshawar Vale, in particular, is vulnerable to recurrent floods due to its unique physiography. Peshawar Vale is drained by River Kabul and its major tributaries namely, River Swat, River Jindi, River Kalpani, River Budhni and River Bara. Kabul River has a length of approximately 700 km, out of which 560 km is in Afghanistan and the rest falls in Pakistan. Looking at the physiography and prevailing flood characteristics, the development of a flood hazard model is required to provide feedback to decision-makers for the sustainability of the livelihoods of the inhabitants. Peshawar Vale is a flood-prone area, where recurrent flood events have caused damages to standing crops, agricultural land, sources of livelihood earnings and infrastructure. The objective of this study was to determine the effectiveness of the ANN algorithm in the determination of flood inundated areas. The ANN algorithm was implemented in C# for the prediction of inundated areas using nine flood causative factors, that is, drainage network, river discharge, rainfall, slope, flow accumulation, soil, surface geology, flood depth and land use. For the preparation of spatial geodatabases, thematic layers of the drainage network, river discharge, rainfall, slope, flow accumulation, soil, surface geology, flood depth and land use were generated in the GIS environment. A Neural Network of nine, six and one neurons for the first, second and output layers, respectively, were designed and subsequently developed. The output and the resultant product of the Neural Network approach include flood hazard mapping and zonation of the study area. Parallel to this, the performance of the model was evaluated using Root Mean Square Error (RMSE) and Correlation coefficient (R2). This study has further highlighted the applicability and capability of the ANN in flood hazard mapping and zonation. The analysis revealed that the proposed model is an effective and viable approach for flood hazard analysis and zonation.

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Review of Flood Hazards Studies in Nepal

The Geographic Base ◽

10.3126/tgb.v7i0.34266 ◽

2020 ◽

Vol 7 ◽

pp. 24-32

Author(s):

Buddhi Raj Shrestha ◽

Raj Kumar Rai ◽

Saroj Marasini

Keyword(s):

Risk Assessment ◽

Flow Model ◽

Flood Hazard ◽

Hazard Analysis ◽

Monsoon Season ◽

Hazard Mapping ◽

Flood Hazards ◽

Journal Articles ◽

Inundation Mapping ◽

Flood Disasters

Flood, a common water-induced disaster of monsoon season, is a recurring phenomenon in Nepal. It causes many deaths and injuries besides severe impacts on the vital infrastructures of the nation. This paper reviews the published national and international journal articles related to flood hazard mapping in Nepal. Desinventar database from 1971-2016 shows that Bagmati province and province 2 are more affected than other provinces in Nepal. Here we review the previous studies on flood disasters at the regional and national levels. The results show that most of the papers are based on a steady flow model for inundation mapping and more focuses on hazard analysis rather than vulnerability and risk assessment.

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Flood vulnerability assessment: A critical comparison between site derived, national and international depth-damage functions and their use in assessing flood risk in Malaysia

10.5194/egusphere-egu21-12731 ◽

2021 ◽

Author(s):

Balqis M. Rehan ◽

Paul Sayers ◽

A. Ulwan M. Alayuddin ◽

M. Fadhil M. Ghamrawi ◽

James D. Miller ◽

...

Keyword(s):

Flood Risk ◽

Flood Hazard ◽

Flood Damage ◽

Damage Function ◽

Kuala Lumpur ◽

Investment Planning ◽

Damage Functions ◽

Flood Vulnerability ◽

Site Specific ◽

Flood Vulnerability Assessment

<p>Damage functions are widely used to determine flood losses. National and international published damage functions are often used with little scrutiny or validation at local scales; a lack of understanding that unquestionably adds uncertainty to national flood risk assessment and investment planning. This paper examines the differences in aggregate flood damage estimates based on damage functions derived locally using local surveys and questionnaires, published national sector-based damage functions and land-use based damage functions published for Malaysia in the international literature. The paper is presented in two parts: firstly, the construction of a damage function from site-specific post-event flood surveys (covering a range of building types and flood hazard variables) and secondly, the comparison of these locally derived function with available national and international functions. A 0.05 km<sup>2</sup> residential area located in Kuala Lumpur, Malaysia, which consists of sparsely located houses was selected for the study. It was used to drive the site-specific damage function and an associated estimate of flood damage for a range of observed and modelled flood events. The results show that at higher depths, the use of the site-specific function suggest an aggregate damage of approximately twice than an estimate based on national functions but much less (less than 100%) than would be estimated based on international published functions. The paper concludes that the international published damage functions should be used with care and condition using local (where possible) or national understanding of flood damages to avoid a significant over estimation of losses.</p>

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Flood Hazard Mapping Using the Flood and Flash-Flood Potential Index in the Buzău River Catchment, Romania

Water ◽

10.3390/w11102116 ◽

2019 ◽

Vol 11 (10) ◽

pp. 2116 ◽

Cited By ~ 1

Author(s):

Mihnea Cristian Popa ◽

Daniel Peptenatu ◽

Cristian Constantin Drăghici ◽

Daniel Constantin Diaconu

Keyword(s):

Risk Management ◽

Flash Flood ◽

Flood Hazard ◽

Flash Floods ◽

Hazard Mapping ◽

Flood Vulnerability ◽

River Catchment ◽

Potential Index ◽

Vulnerability Maps ◽

Two Indices

The importance of identifying the areas vulnerable for both floods and flash-floods is an important component of risk management. The assessment of vulnerable areas is a major challenge in the scientific world. The aim of this study is to provide a methodology-oriented study of how to identify the areas vulnerable to floods and flash-floods in the Buzău river catchment by computing two indices: the Flash-Flood Potential Index (FFPI) for the mountainous and the Sub-Carpathian areas, and the Flood Potential Index (FPI) for the low-altitude areas, using the frequency ratio (FR), a bivariate statistical model, the Multilayer Perceptron Neural Networks (MLP), and the ensemble model MLP–FR. A database containing historical flood locations (168 flood locations) and the areas with torrentiality (172 locations with torrentiality) was created and used to train and test the models. The resulting models were computed using GIS techniques, thus resulting the flood and flash-flood vulnerability maps. The results show that the MLP–FR hybrid model had the most performance. The use of the two indices represents a preliminary step in creating flood vulnerability maps, which could represent an important tool for local authorities and a support for flood risk management policies.

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FLOOD HAZARD MAPPING OF BOGOWONTO RIVER IN PURWOREJO REGENCY, CENTRAL JAVA PROVINCE

Journal of the Civil Engineering Forum ◽

10.22146/jcef.24348 ◽

2017 ◽

Vol 2 (3) ◽

pp. 243 ◽

Cited By ~ 1

Author(s):

Margaretha Titi Pawestri ◽

Joko Sujono ◽

Istiarto Istiarto

Keyword(s):

Flood Hazard ◽

Hazard Mapping ◽

Flood Inundation ◽

Hazard Maps ◽

Flood Events ◽

Hydraulic Modelling ◽

Surrounding Area ◽

Huge Amount ◽

Central Java ◽

Starting Point

The overflowing discharge of Bogowonto River in Purworejo Regency, Central Java flooded the surrounding area during the rainy season. A huge amount of losses such as damage of infrastructures, housing, and agricultural area occurs every year. This research mainly aims to develop flood hazard map and study the characteristics of flood in the study area. There are two main analysis; hydrologic and hydraulic, to model a flood event. Hydrologic and hydraulic modelling of flood based on 20 and 50- years return period hydrograph along the river geometryis done using the latest HEC program namely HEC- HMS 4.1 and HECRAS 5.0. Also, ArcGIS 10.3 is used as a terrain pre-processor and post-processor for hazard mapping. The results of this research are flood hazard maps for 20 and 50 years flood and its comparison to the recent major flood events. Flood inundation modelled covered an area of 993.77 Ha and 1,175.86 Ha, with maximum discharge calculated at Boro Weir as starting point are 1206.2 m3/s and 1,397.3 m3/s for 20 and 50 years flood case, respectively.

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