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

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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Geomorphological hazard analysis along the Egyptian Red Sea coast between Safaga and Quseir

Natural Hazards and Earth System Science ◽

10.5194/nhess-9-751-2009 ◽

2009 ◽

Vol 9 (3) ◽

pp. 751-766 ◽

Cited By ~ 85

Author(s):

A. M. Youssef ◽

B. Pradhan ◽

A. F. D. Gaber ◽

M. F. Buchroithner

Keyword(s):

Red Sea ◽

Urban Areas ◽

Natural Hazard ◽

Hazard Analysis ◽

Hazard Mapping ◽

Hazard Maps ◽

Industrial Facilities ◽

Vulnerability Maps ◽

Legal Restrictions ◽

Sea Area

Abstract. Geomophological hazard assessment is an important component of natural hazard risk assessment. This paper presents GIS-based geomorphological hazard mapping in the Red Sea area between Safaga and Quseir, Egypt. This includes the integration of published geological, geomorphological, and other data into GIS, and generation of new map products, combining governmental concerns and legal restrictions. Detailed geomorphological hazard maps for flooding zones and earth movement potential, especially along the roads and railways, have been prepared. Further the paper illustrates the application of vulnerability maps dealing with the effect of hazard on urban areas, tourist villages, industrial facilities, quarries, and road networks. These maps can help to initiate appropriate measures to mitigate the probable hazards in the area.

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Combination of geomorphic classifiers through Machine Learning-based techniques for flood hazard assessment

10.5194/egusphere-egu21-4723 ◽

2021 ◽

Author(s):

Andrea Magnini ◽

Michele Lombardi ◽

Simone Persiano ◽

Antonio Tirri ◽

Francesco Lo Conti ◽

...

Keyword(s):

Machine Learning ◽

Hazard Assessment ◽

Water Depth ◽

Flood Hazard ◽

Research Centre ◽

Hazard Mapping ◽

Hazard Maps ◽

Flood Hazard Assessment ◽

Flood Prone Areas ◽

Flood Hazard Maps

Every year flood events cause worldwide vast economic losses, as well as heavy social and environmental impacts, which have been steadily increasing for the last five decades due to the complex interaction between climate change and anthropogenic pressure (i.e.&#160;land-use and land-cover modifications). As a result, the body of literature on flood risk assessment is constantly and rapidly expanding, aiming at developing faster, computationally lighter and more efficient methods relative to the traditional and resource-intensive hydrodynamic numerical models. Recent and reliable fast-processing techniques for flood hazard assessment and mapping consider binary geomorphic classifiers retrieved from the analysis of Digital Elevation Models (DEMs). These procedures (termed herein &#8220;DEM-based methods&#8221;) produce binary maps distinguishing between floodable and non-floodable areas based on the comparison between the local value of the considered geomorphic classifier and a threshold, which in turn is calibrated against existing flood hazard maps. Previous studies have shown the reliability of DEM-based methods using a single binary classifier, they also highlighted that different classifiers are associated with different performance, depending on the geomorphological, climatic and hydrological characteristics of the study area. The present study maps flood-prone areas and predicts water depth associated with a given non-exceedance probability by combining several geomorphic classifiers and terrain features through regression trees and random forests. We focus on Northern Italy (c.a. 100000 km2, including Po, Adige, Brenta, Bacchiglione and Reno watersheds), and we consider the recently compiled MERIT (Multi-Error Removed Improved-Terrain) DEM, with 3sec-resolution (~90m at the Equator). We select the flood hazard maps provided by (i) the Italian Institute for Environmental Protection and Research (ISPRA), and (ii) the Joint Research Centre (JRC) of the European Commission as reference maps. Our findings (a) confirm the usefulness of machine learning techniques for improving univariate DEM-based flood hazard mapping, (b) enable a discussion on potential and limitations of the approach and (c) suggest promising pathways for further exploring DEM-based approaches for predicting a likely water depth distribution with flood-prone areas.&#160;

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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 Mapping and Vulnerability Analysis of Bishnumati River, Nepal

Journal on Geoinformatics, Nepal ◽

10.3126/njg.v14i0.16969 ◽

2017 ◽

Vol 14 ◽

pp. 20-24

Author(s):

Susheel Dangol ◽

Arnob Bormudoi

Keyword(s):

Flood Hazard ◽

Hazard Analysis ◽

Flood Plain ◽

Flood Damage ◽

Hazard Mapping ◽

Huge Amount ◽

Technical Approach ◽

Flood Vulnerability ◽

Flood Depth ◽

Flood Intensity

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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Application of Fuzzy TOPSIS to Flood Hazard Mapping for Levee Failure

Water ◽

10.3390/w11030592 ◽

2019 ◽

Vol 11 (3) ◽

pp. 592 ◽

Cited By ~ 7

Author(s):

Tae Hyung Kim ◽

Byunghyun Kim ◽

Kun-Yeun Han

Keyword(s):

Flood Hazard ◽

Multiple Criteria Decision Making ◽

Fuzzy Topsis ◽

Dam Failure ◽

Hazard Mapping ◽

Hazard Map ◽

Hazard Maps ◽

Levee Failure ◽

Flood Hazard Map ◽

Flood Hazard Maps

This paper proposes a new approach to consider the uncertainties for constructing flood hazard maps for levee failure. The flood depth, velocity, and arrival time were estimated by the 2-Dimensional model and were considered as flood indices for flood hazard mapping. Each flood index predicted from the 2-D flood analysis based on several scenarios was fuzzified to reflect the uncertainties of the indices. The fuzzified flood indices were integrated using the Fuzzy TOPSIS (Technique for Order of Preference by Similarity to Ideal Solution), resulting in a single graded flood hazard map. This methodology was applied to the Gam river in South Korea and confirmed that the Fuzzy MCDM (Multiple Criteria Decision Making) technique can be used to produce flood hazard maps. The flood hazard map produced in this study compared with the current flood hazard map of MOLIT (Ministry of Land, Infrastructure and Transports). This study found that the proposed methodology was more advantageous than the current methods with regard to the accuracy and grading of the flood areas, as well as in regard to an integrated single map. This report is expected to be expand upon other floods, including dam failure and urban flooding.

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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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A combined hydrological and hydraulic modelling approach for the flood hazard mapping of the Po river basin

Journal of Flood Risk Management ◽

10.1111/jfr3.12755 ◽

2021 ◽

Author(s):

Rita Nogherotto ◽

Adriano Fantini ◽

Francesca Raffaele ◽

Fabio Sante ◽

Francesco Dottori ◽

...

Keyword(s):

River Basin ◽

Flood Hazard ◽

Hazard Mapping ◽

Hydraulic Modelling ◽

Po River ◽

Po River Basin ◽

Modelling Approach

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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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Flood hazard in the Mekong Delta – a probabilistic, bivariate, and non-stationary analysis with a short-termed future perspective

Natural Hazards and Earth System Sciences Discussions ◽

10.5194/nhessd-1-275-2013 ◽

2013 ◽

Vol 1 (1) ◽

pp. 275-322 ◽

Cited By ~ 3

Author(s):

N. V. Dung ◽

B. Merz ◽

A. Bárdossy ◽

H. Apel

Keyword(s):

Hydrodynamic Model ◽

Large Scale ◽

Flood Hazard ◽

Hazard Analysis ◽

Mekong Delta ◽

Extreme Value ◽

Peak Discharge ◽

Extreme Value Statistics ◽

Hazard Maps ◽

Flood Volume

Abstract. In this paper we present a novel approach for flood hazard analysis of the whole Mekong Delta with a particular focus on the Vietnamese part. Based on previous studies identifying the flood regime in the Mekong delta as non-stationary (Delgado et al., 2010), we develop a non-stationary approach for flood hazard analysis. Moreover, the approach is also bi-variate, as the flood severity in the Mekong Delta is determined by both maximum discharge and flood volume, which determines the flood duration. Probabilities of occurrences of peak discharge and flood volume are estimated by a copula. The flood discharges and volumes are used to derive synthetic hydrographs, which in turn constitute the upper boundary condition for a large-scale hydrodynamic model covering the whole Mekong Delta. The hydrodynamic model transforms the hydrographs into hazard maps. In addition, we extrapolate the observed trends in flood peak and volume and their associated non-stationary extreme value distributions to the year 2030 in order to give a flood hazard estimate for the near future. The uncertainty of extreme flood events in terms of different possible combinations of peak discharge and flood volume given by the copula is considered. Also, the uncertainty in flood hydrograph shape is combined with parameter uncertainty of the hydrodynamic model in a Monte Carlo framework yielding uncertainty estimates in terms of quantile flood maps. The proposed methodology sets the frame for the development of probabilistic flood hazard maps for the entire Mekong Delta. The combination of bi-variate, non-stationary extreme value statistics with large-scale flood inundation modeling and uncertainty quantification is novel in itself. Moreover, it is in particular novel for the Mekong Delta: a region where not even a standard hazard analysis based on a univariate, stationary extreme value statistic exists.

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Large Scale Flood Hazard Analysis by Including Defence Failures on the Dutch River System

Water ◽

10.3390/w11081732 ◽

2019 ◽

Vol 11 (8) ◽

pp. 1732 ◽

Cited By ~ 3

Author(s):

Alex Curran ◽

Karin de Bruijn ◽

Wouter Klerk ◽

Matthijs Kok

Keyword(s):

Flood Risk ◽

Large Scale ◽

Flood Hazard ◽

Hazard Analysis ◽

River System ◽

Overland Flows ◽

Wide Scale ◽

River Loads ◽

Risk Analysis And Management ◽

Modelling Approach

To make informed flood risk management (FRM) decisions in large protected river systems, flood risk and hazard analyses should include the potential for dike breaching. ‘Load interdependency’ analyses attempt to include the system-wide effects of dike breaching while accounting for the uncertainty of both river loads and dike fragility. The intensive stochastic computation required for these analyses often precludes the use of complex hydraulic models, but simpler models may miss spatial inundation interactions such as flows that ‘cascade’ between compartmentalised regions and overland flows that ‘shortcut’ between river branches. The potential for these interactions in the Netherlands has previously been identified, and so a schematisation of the Dutch floodplain and protection system is here developed for use in a load interdependency analysis. The approach allows for the spatial distribution of hazard to be quantified under various scenarios and return periods. The results demonstrate the importance of including spatial inundation interactions on hazard estimation at three specific locations, and for the system in general. The modelling approach can be used at a local scale to focus flood-risk analysis and management on the relevant causes of inundation, and at a system-wide scale to estimate the overall impact of large-scale measures.

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