Non-structural Measures Research Articles

Application of the TELEMAC-2D Model in the Fluvial Hydrodinamics Simulation and Reproduction of Flood Patterns

. The increased occurrence of floods in the city of Rio do Sul (SC), even with the creation of dams to contain floods, show that non-structural measures can be good alternatives to reduce losses in the region. Numerical flood modeling has been widely used to anticipate risks and assist in decisionmaking. One of the numerical models that is being used to simulate floods is TELEMAC-2D, which is able to simulate the hydrodynamics of open channels by solving the shallow water equations in a domain discretized by an unstructured finite element mesh. We used the TELEMAC-2D model tosimulate the dynamics of the rivers of the region of Rio do Sul throughout the year of 2013, period during which a flood with large proportions occurred in September. Fluviometric data avaliable from the National Water Agency and high resolution (1 m) topographic data provided by government agen-cies of Santa Catarina were used in the simulation. The results show that the model performed well in simulating the maximum flood extension occurred in September, however, the simulations were underestimated for most of the time, indicating that calibrations in the model can still be performed.

On the driving forces of historical changes in the fatalities of tropical cyclone disasters in China from 1951 to 2014

Tropical cyclone (TC) disasters have frequently caused casualties in the coastal areas of China. According to the statistics of dead and missing people due to TCs from 1951 to 2014, the number of fatalities has been significantly decreasing over time. However, deadly TC events have still caused great losses of life in recent years, which are characterized as significant abrupt fluctuations superimposed along the downward trend of the long-term fatality time series. The numbers of fatalities caused by TC disasters are influenced by variables such as the intensity of TC hazards, the population exposed to TCs and the vulnerability of people to TC hazards. It is thus of great significance to analyze their temporal characteristics and understand the forces driving these changes. First, the time series of the TC wind, precipitation, spatial distribution of population, fatality and disaster risk reduction (DRR) measures of China from 1951 to 2014 are reconstructed. Second, the improved power dissipation index, total precipitation, integrated intensity and index of exposed population are calculated, and the population vulnerability indices, including mean and relative fatality rates, are derived. Third, the change trend of each index is detected using the Mann–Kendall test. Finally, the main driving factors of the long-term change trend and fluctuations of the TC fatalities are analyzed by a negative binomial regression model and standard deviation statistics. It is found that the decrease in vulnerability based on the improvement in structural and non-structural measures is the main driving force of the decreases in fatalities over the past six decades. Although the total population and exposure have increased dramatically in the coastal areas of China, their contributions to the increase in the fatality risk were counteracted by the decrease in vulnerability. Abrupt and catastrophic disasters were mostly caused by TCs with hazards of high intensity that surpassed the capacity of structural measures; the lack of forecasting or early warning, as well as improper emergency response actions, may also have triggered the great loss of lives. To reduce the fatalities of future TCs, especially those that may exceed the capacity of structural measures, the enhancement of non-structural measures and the adaptation of resilience strategies should be priorities for future people-centered disaster management.

The moderating role of stock markets in the bank competition-entrepreneurship relationship

Using a worldwide database on entrepreneurship dynamics and non-structural measures of competition in banking markets, this paper provides robust international evidence on the macroeconomic impact of bank competition on new business creation. Previous research has shown that the stock market, due to its liquidity externalities, stimulates business creation by allowing and expediting the recycling of “informed capital” supplied to new start-ups by financial intermediaries. Building on the complementarity between banks and stock markets in the business creation process, the paper evaluates in a unifying framework the extent of two competing theories of bank competition effects on entrepreneurial financing. It is found that, in line with the market power hypothesis, bank competition has an overall beneficial impact on new business density by boosting credit access to new entrepreneurs. Yet, consistent with the information hypothesis, this result attenuates as the size of the stock market increases, due to the importance of relationship lending underlying the informed capital recycling.

Criação de áreas de risco: os problemas com alagamentos no distrito de Rio Vermelho, Florianópolis / SC

O presente trabalho trata da criação de áreas de risco a alagamentos no Distrito de Rio Vermelho/SC. Este Distrito possui diferentes tipos de áreas úmidas, porém aquelas localizadas no interior do terraço marinho foram urbanizadas porque nem sempre estão úmidas ao longo do tempo. Moradores antigos sabiam que estas áreas alagavam em episódios de chuvas excepcionais, contudo, são pessoas migrantes que compraram terrenos ali. O parcelamento do solo irregular, sem planejamento e fiscalização do poder público associado ao desconhecimento da dinâmica natural do lugar criaram áreas de risco a alagamento. Medidas estruturais de drenagem não conseguirão acabar com os alagamentos por completo, por isso devem ser implantadas também medidas não-estruturais que diminuam a vulnerabilidade dos moradores.

Advanced Operating Technique for Centralized and Decentralized Reservoirs Based on Flood Forecasting to Increase System Resilience in Urban Watersheds

The frequency of inundation in urban watersheds has increased, and structural measures have been conducted to prevent flood damage. The current non-structural measures for complementing structural measures are mostly independent non-structural measures. Unlike the current non-structural measures, the new operating technique based on flood forecasting is a real-time mixed measure, which means the combination of different non-structural measures. Artificial rainfall events based on the Huff distribution were used to generate preliminary and dangerous thresholds of flood forecasting. The new operation for centralized and decentralized reservoirs was conducted by two thresholds. The new operation showed good performance in terms of flooding and resilience based on historical rainfall events in 2010 and 2011. The flooding volume in the new operation decreased from 6617 to 3368 m3 compared to the current operation in 2010, and the flooding volume in 2011 decreased from 664 to 490 m3. In the 2010 event, the results of resilience were 0.831835 and 0.866566 in current and new operations, respectively. The result of resilience increased from 0.988823 to 0.993029 in the 2011 event. This suggestion can be applied to operating facilities in urban drainage systems and might provide a standard for the design process of urban drainage facilities.

Variation of Geospatial Representation of Community Hazard Maps with Disaster Prevention Activities

Abstract. After the Great Hanshin-Awaji Earthquake, the limitation of assistance by public bodies in the time of such massive natural disaster struck has been recognized. Moreover, it has acknowledged that self-help by suffered families and mutual support of neighbours are crucial to mitigate further damage. Since then, the major focus of the disaster management in Japan has altered to effectiveness of non-structural measures for a forecast crisis. Thus, improving the existing hazard maps into those that show actions to be taken by residents in an easy-to-understand manner has been dictated by the national government.This study discusses the geospatial representation of an alternative hazard map from residents’ perspective with the local community activities. Those mapping activities have been conducted for some years in a study area. Then, the geospatial information represented on the community hazard map has gradually changed. At the early year of the activities, the map represents the certainty of disaster risks. At the late year of those after few modifications have made, the map mainly argues the possibility of risks from residents’ perspective.

Urban flood vulnerability assessments: the case of Dire Dawa city, Ethiopia

Dire Dawa city is identified as one of the most flood-affected cities in Ethiopia. Classifying village-level flood vulnerability using flood indicators is a new approach to Dire Dawa city. Analysis of different flood vulnerability factors underpins sustainable flood risk management and the application of Flood Vulnerability Index (FVI) approach is the hub of this study. Relevant data were collected from 110 households sampled from purposely selected 10 villages found in Dire Dawa city. The flood vulnerability index was used to compare, classify and rank villages in terms of their flood vulnerability levels. For this purpose, 24 sets of indicators which are strongly affecting the levels of flood vulnerability were assessed from social, economic and physical perspectives. The FVI of each village was computed with unequal method of weighting indicators. The findings of the study revealed that Dire Dawa city villages were experiencing varying levels of flood vulnerability. Accordingly, villages 05, 06, 07 and 09 were identified with high flood vulnerability level while villages 03, 04 and 08 and villages 01, 02 and extension village were identified with medium and low level of vulnerability, respectively. Interestingly, the findings of the study confirmed that social factors contributed much for flood vulnerability in Dire Dawa city. Hence, future urban flood risk planning and management endeavors in the city of Dire Dawa must be underpinned by proper utilization of the flood vulnerability map developed addressing social vulnerability component through both structural and non-structural urban flood risk management measures.

Flood risk and its reduction in China

Despite massive flood protection efforts in China, undertaken since the ancient times, disastrous floods continue to plague the country. In this paper, we discuss changes in flood hazard and flood risk in China. First, we review published results (including our own works) on change detection in observed records of intense precipitation, high river flow and flood damage in China. We provide information on essential features of extreme floods in last decades – floods on large rivers, urban floods, and flash floods. Next, we review available projections for the future (including our own results), related to intense precipitation, high river flow and flood damage in China. We try to interpret the difference in flood hazard projections obtained in various publications. Since the spread of river flood hazard projections is large, projections have to be interpreted with caution, because of the impact on decisions related to climate change adaptation, flood risk reduction, and water resources management. We review flood risk reduction strategies in China, focusing on the present situation and division of responsibilities. China has embarked upon an ambitious and vigorous task to improve flood preparedness, by both structural (“hard”) defences, such as: dikes, dams and flood control reservoirs, and diversions, as well as non-structural (“soft”) measures: spatial planning and zoning; watershed management (source control), flood forecasting and warning systems; and awareness raising. The strategy of flood mitigation includes flood retention and urban water management to alleviate the burden of flash and urban flooding.

Effect of Time-Area Percent Curves in Development of Clark Model Unit Hydrograph

This paper describes the effect of time – area percent curves in the development of Clark model unit hydrograph. This hydrology modelling study refers to event base modeling in order to derive the unit hydrograph from Clark instantaneous unit hydrograph. For this study, Kelani river basin up to Hanwella gauging site has been represented as the study area. Hydrologic Modelling System software developed by HEC, USA (HEC-HMS) has been used for the development of unit hydrographs under the Clark UH transform model. Three numbers of different time – area percent curves of Kelani river basin have been asynchronously used as input to the Clark UH transform model in order to obtain different simulations. The parameters, time of concentration Tc and storage coefficient R values were calibrated and validated individually, against the various percent curves for the future analysis. The best suitable percent curve is identified based on the goodness of fit criteria, Nash-Sutcliffe Efficiency (NSE) with high accuracy. For the Loss model, initial and constant rate method was preferred. In the Meteorological Model, Gaged weight was considered for rainfall analysis. For the Transform Model or Direct Runoff Model, Clark UH is considered. For the Base flow model Recession, constant option was preferred. The Calibration (manual and automatic) was conducted for the storm events of May 2017, December 2014 and November 2012.Validation was conducted for the storm event of June 2014. The calibration and validation process was conducted for analyzing the hourly rainfall-runoff data for storm events observed during the monsoon seasons of the relevant years. The conclusions of the study would be very much applicable for the key personnel for taking structural and non-structural measures against the flood menace which is a frequent challenge over the study area concerned.

Bank Competition and its Determinants: Evidence from Indian Banking

This paper measures the degree of bank competition in India using a sample of 70 commercial banks over the period 1996–2016. To assess the degree of competition, we estimate the market power of each bank in our sample employing three nonstructural measures: the Lerner index, the adjusted Lerner index, and the Boone indicator. Bank-wise and year-wise estimates of the marginal cost required in all these measures are obtained using the semi-parametric method. The paper further attempts to undertake a comprehensive assessment of competition in Indian banking and identifies various bank-specific, macroeconomic, structural, and contestability indicators, which are supposed to explain level and variation of the degree of competition over time. Empirical findings reveal that public-sector banks in India exercise a relatively higher degree of bank competition compared to private and foreign-sector banks. However, aggregate results support that the Indian banking system is competitive in general. Unlike the structure-conduct-performance paradigm, which advocates that a concentrated banking system impairs competitiveness, our findings reveal that concentration measures hardly exert any effect on bank competition. Rather, contestability measures play a significant role in the determination of bank competition.

GIS-based spatial multi-criteria approach for characterization and prioritization of micro-watersheds: a case study of semi-arid watershed, South India

An assessment of micro-watersheds based on topography and physical processes is always helpful in identifying suitable locations for implementing soil and water conservation measures. The present study was taken up with the objectives of characterization and prioritization of micro-watersheds using GIS-based spatial multi-criteria approach for a case study area of Andipatti watershed. In order to characterize the micro-watersheds, measurements derived from linear, areal, and relief aspects of the stream network were primarily used as indicators of topography and physical processes. To compute a comprehensive value for each micro-watershed, values of morphometric parameters viz., bifurcation ratio (Rb), drainage density (Dd), stream frequency (Fs), drainage texture (Rt), elongation ratio (Re), circularity ratio (Rc), length of overland flow (Lg), and relief ratio (Rh) were used. Further, quantitative estimation of annual average rates of soil erosion (SE) through the RUSLE method and surface runoff (SR) thorough NRSC-CN method was also integrated with micro-watersheds for ranking purposes. To normalize the rankings of each spatially distributed parameter, weights were derived through the analytical hierarchy process (AHP). Finally, the weighted rankings were summed up and all micro-watersheds are categorized into four priority classes viz. very high, high, moderate, and low. Out of 44 micro-watersheds, 16 micro-watersheds fall under very high priority class signifying the need for watershed conservation measures. Based on the priority index, suitable structural and non-structural measures are suggested to the vulnerable watersheds.

Civil engineering works versus self-protection measures for the mitigation of floods economic risk. A case study from a new classification criterion for cost-benefit analysis

The application of classical cost-benefit analysis to flood risk mitigation measures can be improved by incorporating new comparative parameters, such as the risk-cost ratio, which is defined here for the first time. In addition, applying these analyses not only to the typical public structural measures (dams, dredging, flood storage reservoirs, transverse drainage works), but also to non-structural measures and self-protection (improving housing resistance to flooding, insurance policies), broadens the range of active risk management options. Last two categories are measures with lower initial investment (thus reducing costs) and visual and environmental impact, making them compatible with the EU Water Framework Directives and flood risk management. All these analyses of economic flood risk have been tested in a small Spanish village in the central Iberian Peninsula. For different flooding scenarios, new proposed RCR criterion allow us a rapid and effective quantification of the efficiency of each of the measures, allowing the ordered classification of the same; as well as the weighting of the results according to the particular needs of the decision makers (prioritizing well the reduction of damages, or the necessary economic investment). Thus, the RCR reveals itself as a powerful tool for flood risk management.

Can Land Cover Changes Mitigate Large Floods? A Reflection Based on Partial Least Squares-Path Modeling

Common approaches to large flood management are Natural Water Retention Measures and detention basins. In this study, a Partial Least Squares-Path Model (PLS-PM) was defined to set up a relationship between dam wall heights and biophysical parameters, in critical flood risk zones of continental Portugal. The purpose was to verify if the heights responded to changes in the biophysical variables, and in those cases to forecast landscape changes capable to reduce the heights towards sustainable values (e.g., <8 m). The biophysical parameters comprised a diversity of watershed characteristics, such as land use and geology, surface runoff, climate indicators and the dam heights. The results have shown that terrain slope (w > 0.5), rainfall (w > 0.4) and sedimentary rocks (w > 0.5) are among the most important variables in the model. Changes in these parameters would trigger visible changes in the dam wall height, but they are not easily or rapidly modified by human activity. On the other hand, the parameters forest occupation and runoff coefficient seem to play a less prominent role in the model (w < 0.1), even though they can be significantly modified by human intervention. Consequently, in a scenario of land cover change where forest occupation is increased by 30% and impermeable surfaces are decreased by 30%, interferences in the dam heights were small. These results open a discussion about the feasibility to mitigate large floods using non-structural measures such as reforestation.

Managing Flood in the Context of Education, Research and Partnership in Malaysia

Several structural and non-structural measures and approaches have been implemented by the Malaysian government in order to overcome and alleviate the flood disaster. To date, Education, Partnership and Research have been identified as crucial components in forming an effective Flood Management system in Malaysia. This argument has been supported by many public and private institutions worldwide. As such, the standards and plans can be developed and implemented at district, state and federal levels. The spirits of Hyogo and Sendai were used as the guiding principles. Semi-structured interviews with several responding agencies were conducted for data collection. The findings indicated that less emphasis was given to the roles of components such as Education, Partnership and Research in Flood Management. The aim of this paper is to propose an integrated system for storing, disseminating and analyzing information pertaining to Education, Partnership and Research.

Evaluating local vulnerability and organisational resilience to frequent flooding in Africa: the case of Northern Cameroon

PurposeThe purpose of this paper is to evaluate local vulnerability and organisational resilience including coping/adaptive capacity to climate risks, specifically frequent flooding in Northern Cameroon.Design/methodology/approachThe research is exploratory/deductive and draws upon qualitative methods, secondary and empirical techniques supplemented by semi-structured qualitative interviews with senior disaster managers. Secondary information sources, which include peer review articles, government reports/plans, newspaper articles and other grey literature, enhanced the analysis.FindingsThe research findings have unveiled the physical and social vulnerability of Northern Cameroon to frequent flooding. Results also show that institutional performance for flood management in Cameroon is ineffective, and adaptive capacity is highly deficient. Cameroon’s legislative framework for flood management is weak, and this exacerbates the poor implementation of structural and non-structural flood management measures. Results also indicate issues with relief, evacuation and foreign assistance in flood management. Recommendations that focus on enhancing capacity of response to frequent flooding via reducing vulnerabilities, managing resilience and enhancing adaptive capacity are provided.Originality/valueUsing Gallopin’s (2006) model of vulnerability, this paper makes a distinct contribution by offering insights into the role of adaptive capacity in disaster management systems in developing (African) countries via an evaluation of vulnerabilities and organisational resilience to repeated flooding in Northern Cameroon.

Banking Efficiency: Concepts, Drivers, Measures, Literature and Conceptual Model

This paper attempts to demonstrate the topic of banking efficiency. We try to shed lights on its concepts and types that include a) Pure technical efficiency, b) Scale efficiency, c) Allocative efficiency, d) Cost efficiency and e) Scope efficiency. Then, we move to the drivers of banking efficiency that includes three main groups; the first one is the strategy, the second one is the execution of strategy and finally the environment. Theses three groups are considered as the engine of banking success. Regarding the measures of banking efficiency, they could be divided into structural and non-structural measures. Besides, they are classified into traditional, parametric, and non-parametric measures. Moreover, Data Envelopment Approach (DEA) is the most common measure of efficiency. After illustrating literature review, we elaborate and discuss the conceptual framework of banking efficiency developed by Mokhtar, AlHabashi & Abdullah (2006). This framework categorizes the analysis of banking efficiency into five steps or stages (F1- F5).

Development of a Reliability Index Considering Flood Damage for Urban Drainage Systems

Urban drainage systems are used to safely drain rainwater and prevent urban inundation, and their reliability is usually calculated from the probability of failure, which includes the probability of the drainage facilities being destroyed. This study proposes a new reliability index that includes three factors (flood volume, nodes, and damage), with the aim of prioritizing the structural and nonstructural measures required to improve urban drainage systems. In this study, synthetic rainfall data are generated by the Huff distribution and are used as input data for runoff simulations. The Distance Measure Method that uses a utopian approach is employed here to generate a dimensionless reliability index, as the three factors use different units and no definitive criteria currently exist to determine the weights that should be assigned to each factor. The reliability indexes of flood volume, nodes, and damage determined in this study are 0.7226, 0.4584 and 0.9750, respectively, as the three factors are weighted equally in the reliability index calculation. Using the new method, the reliability index of the city of Jeongup is 0.6484. The new reliability index can be used to assess the effectiveness of various flood mitigation measures in preparation for extreme rainfall events.

Real-Time Integrated Operation for Urban Streams with Centralized and Decentralized Reservoirs to Improve System Resilience

Recently, the number of extreme rainfall events has increased because of climate change. The ever-widening impervious area in urban watersheds also continuously augments runoff volume. Most measures to prevent urban inundation are structural, such as the construction, rehabilitation, and replacement of urban drainage facilities. Because structural measures require time and money, nonstructural measures are also required for the efficient prevention of urban inundation. Current operations in Korea focus on the individual operation of urban drainage facilities while neglecting the status of effluent streams. A study on urban drainage facilities that considers the status of urban streams is necessary to improve the operation of drainage facilities in urban areas. A revised resilience index is suggested to evaluate measures. For the historical rainfall event in 2010, the system resilience for current and integrated operations was 0.199 and 0.238, respectively. For the 2011 event, the system resilience for current and integrated operations was 0.064 and 0.235, respectively. The integrated operation exhibited good performance for the 2010 and 2011 events. Based on the results of this study, an operation as a nonstructural measure for the total management of urban areas is proposed. The revised resilience index could support decision-making processes for flood-management plans.

Pluvial flooding in urban areas across the European continent

Pluvial flooding is a result of overland flow and ponding before the runoff enters any watercourse, drainage system or sewer, or cannot enter it because the network is full to capacity, usually caused by intense rainfall. River and coastal floods get the most attention since they are largest and last the longest, while pluvial floods are relatively marginalized in research. Therefore, the main goal of this research was to show risk posed by pluvial floods, their connection to current global climate change processes, present effects of flooding in European cities, as well as what we can expect in the future. Furthermore, the aims were to present and get more familiar with scientific projects, strategies, directives and measures devised both on national and international levels, that deal with urban pluvial flood issues across the European continent. Climate change projections indicate that there will be an increase in the frequency and intensity of rainfall events throughout Europe and along with ongoing urbanization, the problem of pluvial flooding will most certainly require more attention, which it is starting to receive. Some countries have already developed their strategies and initiatives and implemented both structural and non-structural measures, such as spatial planning, constructional measures, information systems, reducing land sealing through policies, building codes and standards, on-site improvement of retention, infiltration, evaporation, and rainfall water recycling with the use of green roofs, permeable or porous pavements, rain gardening or urban rainwater harvesting. At the same time, there are numerous research papers, studies, conferences and workshops devoted to the problem of pluvial flooding and its management carried out in an attempt to properly deal with this hazard.

Understanding the Barriers Restraining Effective Operation of Flood Early Warning Systems

Over the years, a variety of structural and non-structural measures have been employed by the human societies to counter the growing frequency and intensity of natural disasters. Among the various measures, Early Warning Systems (EWSs) have globally been acknowledged as one of the key non-structural measures for disaster mitigation and preparedness, especially due to their multi-faceted benefits. However, their effective operation during rapid-onset disasters like floods is often disrupted pertaining to a variety of reasons. These manifold reasons have today become critical barriers which restrain the smooth functioning of EWSs. This paper theorizes that the numerous barriers restraining the effective operation of EWSs can primarily be categorized into Knowledge, Technology and Institutional aspects. To support this argument, the study presents an overview of three selected examples of flood disasters in Cameron Highlands (Malaysia), North Kyushu (Japan) and Sri Lanka. Based on published literature, the study lists out key reasons that affected the timely functioning of Flood-EWSs in all the selected cases and explains them in relation to the three theorized categories of barriers. In view of the current limited understanding, this study provides a new perspective for understanding the barriers in EWSs and correspondingly enhancing their operation during disaster situations.