Flood Protection System Research Articles

Water-related disaster risk reduction (DRR) management in the United States: floods and storm surges

Water resources planning and management has evolved in the United States through several distinct stages over the past two centuries, transitioning from a concern for inland waterways transportation to single purpose flood control and finally to multiple purpose large reservoirs. Disaster risk reduction (DRR) was always considered to be one of the main goals of these strategies. Reviewing history, this paper describes a US federal system that presents major challenges to coordinating water resources development and DRR, at both the watershed and metropolitan area scales. The paper reviews the performance of existing flood protection systems of three recent disasters. Federal, state and local responses to these major events have been mixed, as regulatory and management agencies with different evaluation frameworks and decision rules attempt to coordinate their respective responses. The cases revealed new vulnerabilities and weaknesses in the US DRR responses and planning, while contrasting the relative successes of long-term, strategic DRR planning and investments in the case of the Mississippi River and Tributaries (MR&T) system. The paper analyzes this history and recent cases primarily from the perspective of the US Army Corps of Engineers.

Risk to life due to flooding in post-Katrina New Orleans

Abstract. Since the catastrophic flooding of New Orleans due to Hurricane Katrina in 2005, the city's hurricane protection system has been improved to provide protection against a hurricane load with a 1/100 per year exceedance frequency. This paper investigates the risk to life in post-Katrina New Orleans. In a flood risk analysis the probabilities and consequences of various flood scenarios have been analyzed for the central area of the city (the metro bowl) to give a preliminary estimate of the risk to life in the post-Katrina situation. A two-dimensional hydrodynamic model has been used to simulate flood characteristics of various breaches. The model for estimation of fatality rates is based on the loss of life data for Hurricane Katrina. Results indicate that – depending on the flood scenario – the estimated loss of life in case of flooding ranges from about 100 to nearly 500, with the highest life loss due to breaching of the river levees leading to large flood depths. The probability and consequence estimates are combined to determine the individual risk and societal risk for New Orleans. When compared to risks of other large-scale engineering systems (e.g., other flood prone areas, dams and the nuclear sector) and acceptable risk criteria found in literature, the risks for the metro bowl are found to be relatively high. Thus, despite major improvements to the flood protection system, the flood risk to life of post-Katrina New Orleans is still expected to be significant. Indicative effects of reduction strategies on the risk level are discussed as a basis for further evaluation and discussion.

Groundwater monitoring at a building site of the tidal flood protection system “MOSE” in the Lagoon of Venice, Italy

To protect Venice against tidal flooding, the MOSE system (Experimental Electro-mechanic Module) has been under construction since 2003. This safeguarding system is composed of four batteries of mobile barriers at the Lagoon’s inlets (Lido, Malamocco, Chioggia), which will be lifted before the occurrence of exceptional high tides (>1.10 m above the mean sea level), isolating the Venetian Lagoon from the sea. The end of the construction work is foreseen by 2016. In this paper, the results of the groundwater monitoring at the building site of Punta Sabbioni at the Lido inlet are described. A large dewatered basin (tura), formerly occupied by the sea and close to the shoreline, was used for the precasting of the mobile barriers, and the impact of groundwater control was therefore monitored in the phreatic and shallow confined aquifers. Although a slurry wall barrier was excavated to isolate the tura, a drawdown cone in the confined aquifer was observed, extending to 1 km from the construction site. In contrast, the phreatic aquifer was only influenced by tides, rainfall and evapotranspiration, and the slurry wall of the tura had a positive effect of decreasing the groundwater salinity by limiting the seawater intrusion, as confirmed by the electrical conductivity profiles measured inside the piezometers. The monitoring activity was successful in assessing the impacts of the construction work on the aquifer system and in distinguishing them from the effects of natural driving forces.

Rectangular side weirs discharge coefficient estimation in circular channels using linear genetic programming approach

Side weirs are diversion structures extensively used in irrigation, flood protection and combined sewer systems. Accurate estimation of the discharge coefficient (Cd) of side weirs is essential to compute the water surface profile over the weirs and to determine the lateral outflow rate from the system. In this paper, we have utilized a linear genetic programming (LGP) technique to develop new empirical formulas for the estimation of Cd of sharp-edged rectangular side weirs located in circular channels. For this aim, we have employed a total of 1,686 laboratory experimental observations in both sub- and supercritical flow regimes in order to train and validate the proposed models. The performance of the LGP-based models was also compared with those of different multilinear and nonlinear regression models in terms of root mean squared errors, mean absolute errors, and determination coefficient. The results indicated that an explicit LGP-based model using only mathematical functions could be employed successfully in Cd estimation in both sub- and supercritical flow conditions. Genetic-based sensitivity analysis among the input parameters demonstrated that Froude number at upstream of the weir has the most impact on the Cd estimation.

Time-Frequency Methods for Structural Health Monitoring

Detection of early warning signals for the imminent failure of large and complex engineered structures is a daunting challenge with many open research questions. In this paper we report on novel ways to perform Structural Health Monitoring (SHM) of flood protection systems (levees, earthen dikes and concrete dams) using sensor data. We present a robust data-driven anomaly detection method that combines time-frequency feature extraction, using wavelet analysis and phase shift, with one-sided classification techniques to identify the onset of failure anomalies in real-time sensor measurements. The methodology has been successfully tested at three operational levees. We detected a dam leakage in the retaining dam (Germany) and “strange” behaviour of sensors installed in a Boston levee (UK) and a Rhine levee (Germany).

System ochrony przeciwpowodziowej w Polsce. Zadania organów administracji publicznej w fazach zapobiegania i reagowania na zagrożenia powodziowe

Flood protection system in Poland. The tasks of public administration in responses to flood risk
 The article examines the flood protection system in Poland as a part of the national security system. It singles out public offices which are responsible for flood protection and analysis their tasks and competences in emergency management phases. The paper characterises the flood response and preparedness phases. The author emphasizes the preparedness phase as the most significant part of the system.

Role of Probabilistic Methods in Sustainable Geotechnical Slope Stability Analysis

Sustainable stable slope for flood protection systems are of continuing interest, especially among developers of recommended practices and design standards for geotechnical engineers. The Factor-of-Safety, used in conventional deterministic slope stability analyses, is the ratio of the capacity (force, stress, deformation, displacement) of a structure to the demand imposed on or induced in the structure. Such index is clearly evaluated without regard to the degree of uncertainty involved in its calculation that is for instance particularly large for levee slope stability design. This paper advances reliability based slope stability approaches and strategies that address such uncertainties. Probabilistic methods have been successfully applied taking into account two primary categories of uncertainties: natural variabilities and modeling uncertainties.

Floods: Challenges calling for changing action discourse

In the last several years floods have been a regular occurrence in the central and south-eastern Europe. They did occur in the past, but never with such frequency, water levels and consequences. It was exactly those consequences, seen through loss of life, damages on the critical infrastructure, social and private assets, environment and cultural heritage, agricultural losses and pressures on the local, regional and national - already tight - budgets that incited us to change the discourse of action in the face of challenges posed by floods. It is a long term process which demands the change in the concept of deliberation and acting so we could meet the floods in full operative preparedness. In view of this, the goal of the article is the analysis of the reaction of the protection and rescue system of the Republic of Croatia during the catastrophic floods in May 2014, to show Croatia's international activities in providing assistance to Bosnia and Herzegovina and Serbia, and to present suggestions for the improvement of the flood protection system from the civil protection concept.

Marine spawning sites of perch Perca fluviatilis revealed by oviduct-inserted acoustic transmitters

AB Aquatic Biology Contact the journal Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections AB 19:201-206 (2013) - DOI: https://doi.org/10.3354/ab00529 Marine spawning sites of perch Perca fluviatilis revealed by oviduct-inserted acoustic transmitters Mikkel Skovrind1, Emil A. F. Christensen1,*, Henrik Carl1, Lene Jacobsen2, Peter R. Møller1 1University of Copenhagen, Natural History Museum of Denmark, Universitetsparken 15, 2100 Copenhagen, Denmark 2DTU Aqua, Technical University of Denmark National Institute of Aquatic Resources, Section for Freshwater Fisheries Ecology, Vejlsøvej 39, 8600 Silkeborg, Denmark *Corresponding author. Email: mts447@alumni.ku.dk ABSTRACT: In the 1970s, a flood-protection system dramatically changed a large part of the coastal environment of Køge Bugt, a bay in the western Baltic Sea, from open coast to a brackish lagoon habitat. An anadromous stock of European perch Perca fluviatilis seems to have benefitted from this change, but details about their spawning behavior remain unknown. We used oviduct-inserted acoustic transmitters to reveal the pre-spawning behavior and spawning sites of this population. Thirteen female perch were caught in the lower stream basin of St. Vejle Å, and were tagged with acoustic transmitters inserted through the oviduct. The fish were tracked from March 2 to May 24, 2012 with both passive and active telemetry systems. The pre-spawning behavior involved short trips between the stream and adjacent lagoons. Twelve of the 13 transmitters (92%) were expulsed during spawning, providing for the first time a strong proof of concept of oviduct-inserted acoustic transmitters in brackish and marine fish spawning studies. The transmitter expulsions were validated using an egg map, which was based on visual observations of perch egg-strands, and 11 of the 12 expulsed transmitters (92%) were located in areas with eggs. Many fish spawned in the brackish water with salinities up to 9.6 PSU. These salinities are higher than those previously observed for European perch spawning in the wild, and call for further investigations of salinity tolerance in perch eggs. KEY WORDS: Acoustic telemetry · Oviduct · European perch · Salinity · Spawning · Brackish water Full text in pdf format NextCite this article as: Skovrind M, Christensen EAF, Carl H, Jacobsen L, Møller PR (2013) Marine spawning sites of perch Perca fluviatilis revealed by oviduct-inserted acoustic transmitters. Aquat Biol 19:201-206. https://doi.org/10.3354/ab00529 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in AB Vol. 19, No. 3. Online publication date: October 24, 2013 Print ISSN: 1864-7782; Online ISSN: 1864-7790 Copyright © 2013 Inter-Research.

A Bayesian probabilistic approach for impacts of sea level rise on coastal engineering design practice

The real impact of sea level rise (SLR) on coastal and ocean engineering infrastructures is anticipated to be significant. The associated huge costs of coastal flooding and lasting socio-economic crisis would require planners, decision-makers and engineers to use effectively all available knowledge and data to optimize flood defense protection systems. In this paper, we introduce a Bayesian approach that integrates knowledge from previous performance history of structures (data, models and analysis) with more recent information from the simulations performed using the latest data, methods and modeling technology. These two sets of knowledge and information on past and present status of system contain various uncertainties and errors introduced by different input sources and analysis methods. We employ the concept of global uncertainty to quantify the total uncertainty affecting the design, functionality and maintenance of coastal flood defense systems in order to reduce damages resulting from the SLR and other extreme water level changes (e.g., storm surges by hurricanes, increased precipitation and ice melting). Our objective in this paper is to show coastal engineers how to use the prior knowledge with the most current information to improve the safety of flood defense systems. We demonstrate the proposed method in an example for the failure analysis of the 17th Street Flood Wall in New Orleans, where we estimate uncertainties that affected the design of the I-wall. We provide a methodology that integrates the contribution of SLR with all other available prior information to determine uncertainty levels for failure analysis of the flood defenses. Various uncertainties are present in engineering practice, explicit or implicit, and quantification of these is essential to safety and efficacy of coastal flood protection systems.

Urban land for a growing city at the banks of a moving river: Vienna's spread into the Danube island Unterer Werd from the late 17th to the beginning of the 20th century.

In the relation between urban development and the Viennese Danube different periods can be identified from the late 17th to the early 20th century. These periods were strongly intertwined with both the history of the river and the history of the city. Urban expansion into the floodplains is demonstrated in this paper by investigating the island Unterer Werd, next to the city centre. In the late 17th century the fluvial dynamic still hampered urban development on the island. First measures to stabilise the river banks and to protect buildings from floods were taken soon thereafter, but the majority of practices aimed at mitigating the risks and impacts of the frequent floods: inundation was a part of the arrangement and the main target was to minimise the potential impacts. This practice also prevailed after the 1830s, when urban expansion began to move into the north and northwest of the island and the Danube floodplains were considered an important land resource for the growing city. In connection with new technologies and available means to channelise the river, the relationship between Vienna and the Danube changed fundamentally. Urban development in the riverine landscape gained new momentum. This process was initiated before the Great Danube Regulation from 1870 to 1875 was completed, the rate of growth accelerated after 1875. The last decades of the 19th century mark a turning point in the urban development of Vienna, with expanding urban areas becoming dependent upon a well functioning and maintained flood protection system.

A Framework for Assessing Spatial Distribution of Soil Properties in Levee Systems Based on Underlying Geology and River Morphology

Flood protection systems are complex, interconnected engineered systems, where failure at one location means the failure of the entire system. Earthen levees, the systems’ major component, are at risk from many causes of failure including seepage, overtopping, erosion and instability due to seismic loading. Levees stretch for long distances and are formed through various geologic processes and human activities over time, however information regarding soil properties is collected only at limited point locations and varies significantly both laterally and with depth. Prediction of levee performance in locations where no soil data is available becomes a limitation for system risk assessment studies. This study attempts to test the hypotheses that spatial variability of soil properties is correlated to regional variables such as distance from nearest river segment, river meandering sinuosity index and surface geology. A geostatistical ordinary kriging approach was used for developing these correlations. The specific areas used for data collection and analysis and model development in this study were sub-sections of the larger Sacramento River Flood Control Project (SRFCP) in northern California. Soil strength parameters of identified levee stratigraphy layers were statistically analyzed using a geostatistical ordinary kriging approach and correlated to preselected regional variables. Global observations that applied across the study area included the increasing trend of undrained shear strength for cohesive soils, Su, with increasing distance from the river, and decreasing trend of Su with increasing river Sinuosity Index levels. Only local trends were observed in the relation of friction angle of cohesionless soils, ?, with Sinuosity Index, as well as in the relation of Su and ? with geological formations.

Method to Account for Human Intervention in Calculating the Probability of Failure

AbstractAlthough human and organizational factors play a major role in the performance of civil infrastructure, risk assessment does not often explicitly account for them. Although these factors can cause failures, they can also significantly improve a system’s reliability, provided that appropriate procedures are in place to be performed by individuals and the organization as a whole. It is therefore important that engineers, operators, and planners incorporate human and organizational factors into the overall risk-management paradigm. This paper builds on previous risk-assessment methods to develop a framework for quantifying the contribution of human intervention to the overall probability of failure of a system. The six steps of the approach are (1) system definition, (2) conceptual model, (3) event tree, (4) task structure map, (5) quality-management assessment system, and, ultimately, (6) the probability-of-failure computation. The Sherman Island flood-protection system in the Sacramento–San Joaquin...

혼합 검벨분포모형을 이용한 확률강우량의 산정

최근 다양한 기후변동성으로 인해 전 세계적으로 극한호우사상이 동시다발적으로 일어나고 있다. 우리나라의 극한호우사상은 주로 여름철 태풍으로 인한 호우와 국지성 집중호우에 의해서 발생한다. 극한호우사상에 대한 적절한 확률강우량을 추정하기 위해서, 본 연구에서는 연최대치일강우를 태풍으로 인한 강우와 집중호우로 인한 강우로 구분하여 확률적 거동을 고려하였다. 일반적인 강우빈도해석법은 연최대치강우가 단일 모집단을 이룬다고 가정하여 단일 분포함수를 적용하여 확률강우량을 추정하는 반면, 본 연구에서는 연최대치강우를 구성하는 두 가지 호우의 통계적 특성을 수문빈도해석에서 고려하기 위해, 혼합 분포함수를 적용하였다. 비교적 긴 관측강우자료를 보유한 15개 지점을 선정하여, 일강우량에 대한 확률강우량을 산정하고 비교분석을 실시하였다. 혼합 검벨분포모형에 의한 확률강우량은 단일 검벨분포함수를 적용한 확률강우량과 비교하여 지역에 따라 증감이 나타났으며, 이러한 결과는 홍수방어시스템의 계획 및 설계에서 유용한 정보를 제공할 것이다. Recently, due to various climate variabilities, extreme rainfall events have been occurring all over the world. Extreme rainfall events in Korea mainly result from the summer typhoon storms and the localized convective storms. In order to estimate appropriate quantiles for extreme rainfall, this study considered the probability behavior of daily rainfall from the typhoons and the convective storms which compose the annual maximum rainfalls (AMRs). The conventional rainfall frequency analysis estimates rainfall quantiles based on the assumption that the AMRs are extracted from an identified single population, whereas this study employed a mixed distribution function to incorporate the different statistical characteristics of two types of rainfalls into the hydrologic frequency analysis. Selecting 15 rainfall gauge stations where contain comparatively large number of measurements of daily rainfall, for various return periods, quantiles of daily rainfalls were estimated and analyzed in this study. The results indicate that the mixed Gumbel distribution locally results in significant gains and losses in quantiles. This would provide useful information in designing flood protection systems.

Performance of Levees (Stopbanks) during the 4 september 2010 Mw 7.1 Darfield and 22 February 2011 Mw 6.2 Christchurch, New Zealand, Earthquakes

The objective of this paper is to summarize the performance of the levees (or stopbanks) along the Waimakariri and Kaiapoi rivers during the 4 September 2010 Mw 7.1 Darfield and 22 February 2011 Mw 6.2 Christchurch, New Zealand, earthquakes. Shortly after their arrival in the Canterbury area in the mid-nineteenth century European settlers started constructing drainage systems and levees along rivers (Larned et al. 2008). In particular, flooding of the Waimakariri River and its tributaries posed a constant threat to the Christchurch and Kaiapoi areas. The current levee system is a culmination of several coordinated efforts that started in earnest in the 1930s and is composed of both primary and secondary levee systems. The primary levee system is designed for a 450-year flood. Damage estimates for scenarios where the flood protection system is breached have been assessed at approximately NZ$5 billion (van Kalken et al. 2007). As a result, the performance of the levee system during seismic events is of critical importance to the flood hazard in Christchurch and surrounding areas. During the 2010 Darfield and 2011 Christchurch earthquakes, stretches of levees were subjected to motions with peak horizontal ground accelerations (PGAs) of approximately 0.32 g and 0.20 g, respectively. Consequently, in areas where the levees were founded on loose, saturated fluvial sandy deposits, liquefaction-related damage occurred ( i.e. , lateral spreading, slumping, and settlement). The performance summary presented herein is the result of field observations and analysis of aerial images (New Zealand Aerial Mapping 2010, 2011), with particular focus on the performance of the levees along the eastern reach of the Waimakariri River and along the Kaiapoi River. In the sections that follow, we first present background information about the levee system. This is followed by an overview of the performance of the levees during the Darfield …

OPPORTUNITIES AND DRAWBACKS OF MOBILE FLOOD PROTECTION SYSTEMS

Permanent flood protection systems like dykes and protection walls offer a high level of protection against flooding and need only little maintenance during flood events. Therefore, most high-risk areas are protected by permanent constructions. Problems arise in densely populated areas where no space for dykes is available and less space consuming flood protection walls would cut off traffic lines and obstruct view axes. In these cases, mobile flood protection measures may be a solution to fit both requirements: protection in case of flooding and open access to the floodplain over the remaining time. Furthermore, mobile protective systems can be used as emergency tool against flooding in unprotected low-lying areas and for heightening of permanent flood protection structures in extreme events.
 Planning criteria of mobile flood protection like types of application, early warning and deployment time, required personnel, structural failure mechanisms, financial aspects, and essential information politics are discussed in this paper. As the available constructions differ in material, construction, permanent facilities, available protection height, and safety level, a systematization of mobile flood protection systems as well as opportunities and drawbacks of the described constructions are given.

Reducing Erosion of Earthen Levees Using Engineered Flood Wall Surface

Erosion was one of the major causes for the failure of New Orleans levee system during Hurricane Katrina. Protection of flood walls from erosion failure can be achieved in many different ways. This study consisted of experimental research to develop engineered flood wall surfaces that can reduce the erosion energy of the plunging water before the water hits the levee surface, so that the flood protection system becomes more resilient. Test results were compared to hydrodynamics simulation results by using FLOW3D. The results revealed that the erosion resistance of levees can be substantially reduced by providing protective structures at the surface of the flood walls. An effectively designed protective structure could reduce the erosion depth as much as 40% and extend the erosion time as much as 400%.

Erosion Control Using Modified Soils

As a result of Hurricane Katrina, many sections of the flood protection systems in New Orleans were eroded due to plunging water, and sections of flood walls were determinately damaged. Therefore, mitigating this type of erosion and failure is necessary for counteracting similar catastrophic events. This study evaluated the method to mitigate erosion due to plunging water by strengthening the soil with ground modification. The Vetiver plant and Polyhedral Oligomeric Silsesquioxanes (POSS) were the two main ground modifiers used in this test. Test results showed that both POSS and the Vetiver were effective in reducing erosion. POSS showed good erosion resistance with good applicability to field soils; Vetiver showed higher resistance to erosion by plunging water, but required time to achieve a well established root/stem system.

Multiscale modelling in real-time flood forecasting systems: From sand grain to dike failure and inundation

Abstract Severe events around the globe have highlighted the threat to life, infrastructure and the environment posed by flooding. Flood forecasting systems are a vital component of broader flood risk management activities. These systems are becoming increasingly more sophisticated as their importance in reducing life loss and economic damages is realized. Part of this increase in complexity is focused on the ability to predict and warn of failures in dykes, levees and embankments. A new European ICT project, UrbanFlood for Environmental Services and Climate Change Adaptation, has recently been commissioned and is introduced in this presentation. The primary objective of the Urban Flood project is to develop early warning systems that will monitor flood protection systems in real-time, identify vulnerable locations, model the failure and predict dike collapse and subsequent inundation. In combination with the damage assessment, Urban Flood will serve as an advanced decision support system, mitigating the impact of seasonal and catastrophic floods. Modeling is one of the key tasks in the project. The models will be required to simulate the behavior of the material properties of the layered dikes (sand, clay, peat, grass or concrete cover, metal frame, dam gates, etc.), during extreme hydraulic loading events. In earthen dikes, extra challenge is posed by the non-linear elastic plastic properties of the deformable clay. A realistic simulation of the dike will model the free-surface water dynamics; convective and diffusive transfer of water inside the porous materials; dynamic response of clay to the water pressure; structural mechanics, deformation and actual dike breakdown and flood. The models shall cover a wide range of scales from a sand grain to a flooded city. The time scales will range from seconds (for water penetrating the soil) to hours (for dike collapse dynamics and ocean tides). Eventually, the models will predict the influence of seasonal and global changes on the stability of flood defense systems. Full 3D transient simulation of dike failure with subsequent inundation will require significant computing resources. The project started three months ago, and we will present the plan for developing the modeling cascade for the system. This work is supported by the UrbanFlood European Union project N 248767, theme ICT-2009.6.4

The Development of a Flood Protection System for Pad Transformers Using Pneumatic Pressure in Areas Prone to Floods

The inundation of substation and ground power equipment breaks out every summer season in low-lying downtown areas and low-lying shores by torrential rain, typhoons and tsunamis. It has, in turn, caused replacement, social and economic costs for blackouts. For activity management regarding flood damage we produced a flood protection system which using the Pad transformer as a basic frame and is developed using pneumatic pressure. We tested safety concerns including insulation resistance and current leakage first for water tank flooding and, second, by an empirical test through supplying 22.9[㎸]. We estimate that costs associated with flooding and power failure can be diminished by these advances toward creating a more reliable system.