scholarly journals Flood Control by Weir Design Using HEC-RAS Model: The Case of Al-Musandaq Escape

2021 ◽  
Vol 877 (1) ◽  
pp. 012025
Author(s):  
Tabarak W. Mahdi ◽  
Ali N. Hillo
Keyword(s):  
Input Data ◽  
Flood Control ◽  
Model Simulation ◽  
Flood Hazard ◽  
Environmental Safety ◽  
Optimal Level ◽  
Clear Understanding ◽  
Optimum Level ◽  
Flood Depth ◽  
Elevation Model

Abstract Proper flood control plays an important part in designing hydraulic structures and environmental safety measures. However, in Iraq, a clear understanding either of the estimation or management of the magnitude of flooding is yet to reach a higher level. This has resulted in grave and frequent damage to much property and life in Maysan town. Therefore, this study was focused on the Flood Hazard contro; in the River Tigris at the downstream of Al-Kut Barrage to the Al-Musandaq Escape, by adopting the HEC RAS model. Here, information related to the hydrological and topographical Digital Elevation Model (DEM) data were used as the input data. The hydrological data enabled the estimation of the flood depth of the river, for April 2019. All the geometric data were prepared by the HEC-RAS model. The unsteady-state model simulation was performed employing the input data. In this study, the best method for flood control and management is to design a weir having an optimal level, the optimum level that does not permit the passage of a flow that exceeds 700 m3/s to the city of Maysan during the flood season and a flow that is not below 250 m3/s during the dry season, is 9.406 m.

scholarly journals Effectiveness of Nature-Based Solutions in Mitigating Flood Hazard in a Mediterranean Peri-Urban Catchment

Water ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2893
Author(s):  
Carla S.Ferreira ◽  
Sandra Mourato ◽  
Milica Kasanin-Grubin ◽  
António J.D. Ferreira ◽  
Georgia Destouni ◽  
...  
Keyword(s):  
Water Depth ◽  
Model Simulation ◽  
Flood Hazard ◽  
Coupled Model ◽  
Urban Catchment ◽  
Rainfall Events ◽  
Flood Depth ◽  
Mitigation And Adaptation ◽  
Flood Magnitude ◽  
Central Portugal

Urbanization alters natural hydrological processes and enhances runoff, which affects flood hazard. Interest in nature-based solutions (NBS) for sustainable mitigation and adaptation to urban floods is growing, but the magnitudes of NBS effects are still poorly investigated. This study explores the potential of NBS for flood hazard mitigation in a small peri-urban catchment in central Portugal, prone to flash floods driven by urbanization and short but intense rainfall events typical of the Mediterranean region. Flood extent and flood depth are assessed by manually coupling the hydrologic HEC-HMS and hydraulic HEC-RAS models. The coupled model was run for single rainfall events with recurrence periods of 10–, 20–, 50–, and 100–years, considering four simulation scenarios: current conditions (without NBS), and with an upslope NBS, a downslope NBS, and a combination of both. The model-simulation approach provides good estimates of flood magnitude (NSE = 0.91, RMSE = 0.08, MAE = 0.07, R2 = 0.93), and shows that diverting streamflow into abandoned fields has positive impacts in mitigating downslope flood hazard. The implementation of an upslope NBS can decrease the water depth at the catchment outlet by 0.02 m, whereas a downslope NBS can reduce it from 0.10 m to 0.23 m for increasing return periods. Combined upslope and downslope NBS have a marginal additional impact in reducing water depth, ranging from 0.11 m to 0.24 m for 10– and 100–year floods. Decreases in water depth provided by NBS are useful in flood mitigation and adaptation within the peri-urban catchment. A network of NBS, rather than small isolated strategies, needs to be created for efficient flood-risk management at a larger scale.

scholarly journals Flood Hazard Mapping in Residential Area Using Hydrodynamic Model HEC-RAS 5.0

2020 ◽  
Vol 7 (1) ◽  
pp. 25-36
Author(s):  
Muhammad Baitullah Al Amin ◽  
Reini Silvia Ilmiaty ◽  
Ayu Marlina
Keyword(s):  
Flow Velocity ◽  
Hydrodynamic Model ◽  
Flood Control ◽  
Flood Hazard ◽  
Hazard Mapping ◽  
Residential Areas ◽  
Low Level ◽  
Flood Depth ◽  
Two Dimensional Flow ◽  
Hazard Rating

The flood hazard rating is one of the essential variables in flood risk analysis. The identification of flood-prone areas urgently requires information about flood hazard zones. This research explains the method to develop flood hazard map by using hydrodynamic modeling in the residential areas. The hydrodynamic model used in this research is HEC-RAS 5.0, which can simulate the one- and two-dimensional flow regimes. The study area is Bukit Sejahtera and Tanjung Rawa residences located in Palembang City with a total area of about 200 ha, where the Lambidaro River was frequently overflowing caused flood inundation in the area. There are five indicators of flood hazard being analyzed, i.e., 1) flood depth, 2) flow velocity, 3) energy head, 4) flow force, which is the result of multiplication between flood depth and the square of flow velocity, and 5) intensity, which is the result of multiplication between flood depth and the flow velocity. The simulation results show that the flood hazard rating in the study area ranges from high to low level. The zones with a high flood hazard rating are dominated by the area around or near to the river, whereas the further zones have a moderate and low level of flood hazard rating. The flood depth indicator has a more significant influence than the flow velocity on the flood hazard level in the study area. This research is expected can contribute to the development of flood map and flood control methods in advance.

scholarly journals A Case Study of Flood Risk Evaluation Based on Emergy Theory and Cloud Model in Anyang Region, China

Water ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 420
Author(s):  
Zening Wu ◽  
Yuhai Cui ◽  
Yuan Guo
Keyword(s):  
Risk Assessment ◽  
Flood Risk ◽  
Flood Control ◽  
Flood Hazard ◽  
Cloud Model ◽  
Flood Disaster ◽  
Assessment System ◽  
Assessment Model ◽  
Flood Risk Assessment ◽  
Emergy Theory

With the progression of climate change, the intensity and frequency of extreme rainfall have increased in many parts of the world, while the continuous acceleration of urbanization has made cities more vulnerable to floods. In order to effectively estimate and assess the risks brought by flood disasters, this paper proposes a regional flood disaster risk assessment model combining emergy theory and the cloud model. The emergy theory can measure many kinds of hazardous factor and convert them into unified solar emergy (sej) for quantification. The cloud model can transform the uncertainty in flood risk assessment into certainty in an appropriate way, making the urban flood risk assessment more accurate and effective. In this study, the flood risk assessment model combines the advantages of the two research methods to establish a natural and social dual flood risk assessment system. Based on this, the risk assessment system of the flood hazard cloud model is established. This model was used in a flood disaster risk assessment, and the risk level was divided into five levels: very low risk, low risk, medium risk, high risk, and very high risk. Flood hazard risk results were obtained by using the entropy weight method and fuzzy transformation method. As an example for the application of this model, this paper focuses on the Anyang region which has a typical continental monsoon climate. The results show that the Anyang region has a serious flood disaster threat. Within this region, Linzhou County and Anyang County have very high levels of risk for flood disaster, while Hua County, Neihuang County, Wenfeng District and Beiguan District have high levels of risk for flood disaster. These areas are the core urban areas and the economic center of local administrative regions, with 70% of the industrial clusters being situated in these regions. Only with the coordinated development of regional flood control planning, economy, and population, and reductions in the uncertainty of existing flood control and drainage facilities can the sustainable, healthy and stable development of the region be maintained.

scholarly journals A metric-based assessment of flood risk and vulnerability of rural communities in the Lower Shire Valley, Malawi

2015 ◽  
Vol 370 ◽  
pp. 139-145 ◽  
Author(s):  
A. J. Adeloye ◽  
F. D. Mwale ◽  
Z. Dulanya
Keyword(s):  
Rural Communities ◽  
Spatial Variability ◽  
Flood Risk ◽  
Flood Hazard ◽  
Sub Saharan Africa ◽  
Structured Interviews ◽  
Adaptation Measures ◽  
Flood Depth ◽  
Inundation Area ◽  
Sub Saharan

Abstract. In response to the increasing frequency and economic damages of natural disasters globally, disaster risk management has evolved to incorporate risk assessments that are multi-dimensional, integrated and metric-based. This is to support knowledge-based decision making and hence sustainable risk reduction. In Malawi and most of Sub-Saharan Africa (SSA), however, flood risk studies remain focussed on understanding causation, impacts, perceptions and coping and adaptation measures. Using the IPCC Framework, this study has quantified and profiled risk to flooding of rural, subsistent communities in the Lower Shire Valley, Malawi. Flood risk was obtained by integrating hazard and vulnerability. Flood hazard was characterised in terms of flood depth and inundation area obtained through hydraulic modelling in the valley with Lisflood-FP, while the vulnerability was indexed through analysis of exposure, susceptibility and capacity that were linked to social, economic, environmental and physical perspectives. Data on these were collected through structured interviews of the communities. The implementation of the entire analysis within GIS enabled the visualisation of spatial variability in flood risk in the valley. The results show predominantly medium levels in hazardousness, vulnerability and risk. The vulnerability is dominated by a high to very high susceptibility. Economic and physical capacities tend to be predominantly low but social capacity is significantly high, resulting in overall medium levels of capacity-induced vulnerability. Exposure manifests as medium. The vulnerability and risk showed marginal spatial variability. The paper concludes with recommendations on how these outcomes could inform policy interventions in the Valley.

scholarly journals Erosion Prediction Model using Fractional Vegetation Cover

2020 ◽  
Vol 5 (1) ◽  
pp. 125-132
Author(s):  
Nursida Arif ◽  
Projo Danoedoro ◽  
Hartono Hartono ◽  
Andrew Mulabbi
Keyword(s):  
Prediction Model ◽  
Vegetation Cover ◽  
Input Data ◽  
Medium Density ◽  
Vegetation Density ◽  
Erosion Model ◽  
Fractional Vegetation Cover ◽  
Erosion Prediction ◽  
Digital Elevation ◽  
Elevation Model

The purpose of this study was to  create an erosion prediction model in Serang Watershed, Indonesia. The erosion model used two input data, namely the slope derivied from Digital Elevation Model (DEM) data, and Fractional Vegetation Cover (FVC) from SPOT images. Assessment of the model was carried out using questionnaires and interviews with several experts by presenting the results of the model and its supporting data. Based on the DEM data, the level of slope steepness in the study area is very varied namely; flat (52.77%), sloping (7.62%), and rather steep to very steep (39.59%). Vegetation density according to the FVC results is dominated by medium density. The results of the analysis of the two input models can provide predictions of the level of erosion with an accuracy of 67.92%. Evaluation of the model was done by experts with conclusions that the method was very flexible and can be adapted to similar watersheds elsewhere.

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

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

Calcific Uremic Arteriolopathy

2013 ◽  
Vol 24 (3) ◽  
pp. 285-300
Author(s):  
Kimberly G. Anderson
Keyword(s):  
Early Recognition ◽  
Renal Dialysis ◽  
Optimal Level ◽  
Health Care Team ◽  
Team Approach ◽  
Clear Understanding ◽  
Treatment Plans ◽  
Calcific Uremic Arteriolopathy ◽  
Stage Renal Disease ◽  
End Stage

Calcific uremic arteriolopathy is a little understood diagnosis of increasing prevalence seen predominantly in patients with chronic kidney disease, particularly those who are approaching end-stage renal disease, who are undergoing renal dialysis, and who have secondary hyperparathyroidism. Calcific uremic arteriolopathy affects women more frequently than men, at a ratio of 3:1, and the median age at diagnosis is 48 years. A clear understanding of the pathogenesis and definitive plans of care are lacking. Nurses should be familiar with the clinical picture of calcific uremic arteriolopathy. Early recognition is important to develop optimal treatment plans and to limit progression of this rare but often fatal disease. Nurses have a pivotal role in maintaining the patient’s comfort and dignity, while setting realistic goals of care. Calcific uremic arteriolopathy remains a rare and complex clinical condition that requires a multidisciplinary health care team approach to provide the optimal level of care. Nurses have an essential role in the care of patients with the diagnosis of calcific uremic arteriolopathy.

scholarly journals Analysis and Projection of Flood Hazards over China

Water ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 1022 ◽  
Author(s):  
Yulian Liang ◽  
Yongli Wang ◽  
Yinjun Zhao ◽  
Yuan Lu ◽  
Xiaoying Liu
Keyword(s):  
21St Century ◽  
Flood Control ◽  
Climate Model ◽  
Southern China ◽  
Flood Hazard ◽  
Global Climate ◽  
Global Climate Model ◽  
Flood Hazards ◽  
Rcp Scenarios ◽  
Meteorological Observations

Floods have been experienced with greater frequency and more severity under global climate change. To understand the flood hazard and its variation in the future, the current and future flood hazards in the 21st century in China are discussed. Floods and their trends are assessed using the accumulation precipitation during heavy rainfall process (AP_HRP), which are calculated based on historical meteorological observations and the outputs of a global climate model (GCM) under three Representative Concentration Pathway (RCP) scenarios. The flood-causing HRPs counted by the flood-causing critical precipitation (the 60% fractile of AP_HRP) capture more than 70% of historical flood events. The projection results indicate that the flood hazards could increase under RCP4.5 and RCP8.5 and increase slightly under RCP2.6 during the 21st century (2011–2099). The spatial characteristics of flood hazards and their increasing trends under the three RCPs are similar in most areas of China. More floods could occur in southern China, including Guangdong, Hainan, Guangxi and Fujian provinces, which could become more serious in southeastern China and the northern Yunnan province. Construction of water conservancy projects, reservoir dredging, improvement of drainage and irrigation equipment and enhancement of flood control and storage capacity can mitigate the impacts of floods and waterlogging on agriculture.

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

Geofizika ◽  
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.

scholarly journals Flood depth estimation by means of high-resolution SAR images and LiDAR data

2018 ◽  
Author(s):  
Fabio Cian ◽  
Mattia Marconcini ◽  
Pietro Ceccato ◽  
Carlo Giupponi
Keyword(s):  
High Resolution ◽  
Urban Areas ◽  
Depth Estimation ◽  
Flood Depth ◽  
Inundation Depth ◽  
Detection Approach ◽  
Digital Elevation ◽  
Radar Imagery ◽  
Elevation Model ◽  
Terrain Elevation

Abstract. When floods hit inhabited areas, great losses are usually registered both in terms of impacts on people (i.e., fatalities and injuries) as well as economic impacts on urban areas, commercial and productive sites, infrastructures and agriculture. To properly assess these, several parameters are needed among which flood depth is one of the most important as it governs the models used to compute damages in economic terms. This paper presents a simple yet effective semi-automatic approach for deriving very precise inundation depth. First, precise flood extent is derived employing a change detection approach based on the Normalized Difference Flood Index computed from high resolution Synthetic Aperture Radar imagery. Second, by means of a high-resolution Light Detection And Ranging Digital Elevation Model, water surface elevation is estimated through a statistical analysis of terrain elevation along the boundary lines of the identified flooded areas. Experimental results and quality assessment are given for the flood occurred in the Veneto region, North-Eastern Italy, in 2010. In particular, the method proved fast and robust and, compared to hydrodynamic models, it requires sensibly less input information.

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