Dissertations / Theses: 'Urban flood modeling'

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Lant, Jeremiah. "A Hydraulic Modeling Framework for Producting Urban Flood Maps for Zanesville, Ohio." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1306933258.

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Liu, Yuling. "Multi-Agent Based Modeling and Simulation of Flood Evacuation Decision-Making Considering Dynamics of Urban Life." 京都大学 (Kyoto University), 2010. http://hdl.handle.net/2433/120843.

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Grimley, Lauren Elise. "Urban and rural flood forecasting: a case study of a small town in Iowa." Thesis, University of Iowa, 2018. https://ir.uiowa.edu/etd/6118.

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Floods are the most common natural disaster in the U.S. as reported by the Federal Emergency Management Administration (FEMA), and there is a need to provide advance warning to vulnerable communities on the potential risks of flooding after intense storms. The key drivers of urban hydrological research include climate change impacts and adaption, city resilience to hydrological extremes, and integration with emergency management and city planning disciplines. Significant advances in modeling techniques and computational resources have made real-time flood forecasting tools in urban and rural areas an achievable goal, but there is no universal method for flood modeling. Urban landscapes pose a challenge because of fine-scale features and heterogeneities in the landscape including streets, buildings, pipes, and impervious land cover. A nested regional-local modeling approach was used to evaluate its capabilities to provide useful and accurate flood related information to a small community in Iowa. The advantage of a nested approach is the ability to harness the computational efficiency of the regional model while providing reasonably accurate streamflow boundary conditions to the local model. The nested model incorporates the tools and products maintained at the Iowa Flood Center (IFC) including the streamflow bridge sensors, rain gauges, radar rainfall product, and statewide model. A one-way connection was made between the regional model of the upper Maquoketa Watershed (275 mi2) and the local model of the City of Manchester (5 mi2). The uncalibrated, nested model was validated using photos and streamflow records for flood events that occurred in July 2010 and September 2016. Multiple radar rainfall estimates were used as input to the model to better understand the impacts of the spatial and temporal resolution and variations of rainfall on streamflow predictions. A local storm event analysis was completed to determine the vulnerable areas of the stormwater network in eastern Manchester. The two main sources of flooding in Manchester are from the river and from local runoff. During extreme flood events caused by the river, the hydrologic impacts of the urban catchment are masked and the stormwater network system is overwhelmed. The coarse, regional model is limited in producing streamflow results for the small tributaries draining the eastern areas of Manchester. In the case of localized rainfall, a fine resolution model that takes into account the stormwater network and rainfall-runoff dynamics are crucial to capturing the hydrologic response of the urban area. Overall, the nested model showed skill in reproducing the hydrographs and the flood extents. Using an ensemble of rainfall input, the multiple model realizations envelope the observed streamflow indicating that the uncertainty of the rainfall is implicitly captured in the model results. The simulated streamflow at the outlet varies significantly depending on the spatial resolution of the rainfall but shows small sensitivity to the temporal resolution of the rainfall input. However, the local rainfall-runoff volumes vary significantly depending on the spatial and temporal resolution of the rainfall input. Recommendations are given to Manchester to highlight areas at risk to flooding. Recommendations are given to the IFC on the capabilities of the nested regional-local modeling approach along with suggestions for future work to incorporate urban areas into the statewide flood forecasting system.

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Stanley, Christopher. "Flood Visualization for Urban Planning : An exploratory spatiotemporal visualization of storm water runoff in 2D and 3D." Thesis, Högskolan i Gävle, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-21822.

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Modelling hydrologic processes is important for understanding how the water cycle works in different environments. Cities which undergo constant changes are subject to flood hazards resulting from severe rainfall. This paper aims to simulate severe rainfall, visualize the results, incorporating both spatial and temporal dimensions, and to make future recommendations for further studies on flood visualization. Visualizing the results from a rainfall simulation using GIS provides urban planners and others the means to view the dynamics of the surface runoff. At the same time, it makes accessible advanced querying and analytical tools. A hydrological model for the study area in Gävle, Sweden was used to simulate a 100-year rainfall. Through FME, the data was reduced, time-stamped and combined to a shapefile. Both 2D software, ArcGIS, and 3D software, ArcScene, were used for creating an animated flood visualization. This study shows that although 2D tested better by a group of planners and water professionals, the 3D was still considered more intuitive. The heightened sense of realism from 3D outweighs its drawbacks, and further studies are required to test different methods of 3D visualization.

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Henrich, Michael. "The influence of temporal rainfall distribution and storm movement on flood depth in urban pluvial cloud burst modeling." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-265572.

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Pluvial floods are the most difficult and to date least investigated phenomena in urban hydrology. While efforts are being made to increase the knowledge base concerning this type of flooding, a large part of the difficulty lies in the nature of the precipitation. Convective storms represent most of the larger intensity short term rainfall in urban areas and is also the raintype, that is expected to increase the most in the future. The rain cells of this type have a more distinct boundary, larger intensity, a smaller extent and a shorter life span, than frontal rains. Combined with the low availability of densely spaced rain gauge networks and also low temporal resolution of measurements in 15 minutes intervals at best, makes this rain type still very difficult to analyze and even harder to predict. The resolution of cloud radar images at 2x2km and taken every 15 minutes is too coarse and the error reduction algorithms for radar based precipitation (HIPRAD) images to analysera in patterns are not sufficient by them selves to analyze the characteristics of such rainfields and the processes occurring within these fields. The spatial variation of raincells, their development and decay, the distance between them, and the velocity and direction of their movement can however be investigated employing a combination of densely spaced rain gauges and radar images to reach a more realistic representation of short-term precipitation for the use of in hydraulic models. The movement of rain fields has been investigated with two main areas of focus: The influence of direction or directional bias, often with an interest in the most crucial case referred to as the resonance effect, and in context of areal reduction of point rainfall. Most of these studies have been carried out with statistical methods and in laboratory experiments. In this study a hydraulic model was built on the terrain model of a realcity, a 28 km area in the city of Falun, to test the recently gathered information about the temporal variation of five empirical hyetographs with different peak arrival times and peak intensities, which are representative of Swedish climate. The hyetographs were produced and provided by SMHI. The empirical rain types were derived from 20 years of rain gauge observations and confirmed by radar images. For reference purposes, a standard Chicago design storm (CDS) rain was modeled as well. The simulated scenarios were modeled as a MIKE 21 hydraulic model, as a stationary scenario and in four movement directions. It was foundthat the empirical rain types produced lower inundation depth than the CDS, in a range of 20 to 50 % lower. The effect of modeling rainfall in motion produced on average only about 4-20 % lower water depths than the corresponding non-moving scenario. In a few instances, in a single evaluation point, the moving scenarios resulted in a relative water depth of a maximum of just above 1%. It was concluded that the conceptual approach of areal reduction from movement seems to be accurate and could help improve modeling rainfall in general, and specifically for cloud burst scenarios of shorter durations in urban catchments. It was also found that further investigation of the physical processes in rainfields could serve to increase the accuracy in areal reduction of precipitation for more realistic hydraulic models and in turn reduce over design.
Pluviala översvämningar är den typen, som är både svårast att reda ut och samtidigt den minst utforskade fenomenen inom urban hydrologi. Medan ansträngningar görs för att förbättra kunskapsläget, ligger den största svårigheten i nederbördens skepnad. Det är konvektiva regn som utgör de flesta av de starkare korttids regntillfällen i urbana områden och är också regntypen som förväntas att öka mest i framtiden. Regncellerna har en tydligare avgränsning, en större intensitet, mindre utsträckning, och en kortare livscykel än frontala regn. I kombination med den låga tillgängligheten av regnmätarnätverk med hög täthet i positioneringen av mätare, samt den låga tidsupplösningen av mätningar i intervaller av 15 minuter gör att konvektiva regn fortfarande är svåra att analysera och ännu svårare att förutse. Upplösningen av molnradar bilder av 2x2 km som tas varje 15:de minut är för grova och algoritmer för felreducering av bilder från radarbaserad nederbördsdata (HIPRAD) för analys av regn mönster är inte tillräckligt noggranna, för sig, för att kunna analysera egenskaperna av sådana regnfält och de processerna som karakteriserar dessa. Den spatiala variationen inom regnceller, deras utveckling och förfall, avståndet mellan dem samt riktningen och hastigheten kan ändå undersökas med hjälp av kombinationen av regnmätarnätverk och radar bilder för att uppnå mer realistiska korttids nederbördsscenarier för användning i hydrauliska model. Studier, som har undersökt regn i rörelse har varit fokuserade på två huvudområden: Betydelsen av riktningen, i vilken regnet rör sig, där den största effekten som denna riktningsbias kan uppnå, har döpts resonans effekt och i samband med ytreducering (areal reduction) av punkt nederbörd. De flesta av dessa studier har genomförts med hjälp av statistiska metoder och laboratorieexperiment. I denna studie skapades en hydraulisk modell baserad på en realistisk terräng av ett existerade urbant område, en yta på 28 km i Falun, för att testa den nyligen utvärderade informationen om temporala intensitets fördelningen som representerar det svenska klimatet. Regndatat producerades och tillhandahölls av SMHI och representerar en mätserie från regnmätare över en period av 20 år. Som referens modellerades även ett Chicago regn (CDS). Med hjälp av en MIKE21 hydraulisk modell, simulerades ett stationärt scenario och fyra rörelseriktningar för varje empirisk hyetograf. Resultaten visade att de empiriska regntyperna skapade översvämningar med 20-50% lägre vattendjup än CDS regnet. Att modellera rörelsen resulterade i 4-20% lägre vattennivåer jämfört med respektive stationär scenario. I några enstaka tillfällen, i en av evalueringspunkterna, skapade de rörliga scenarierna större resultat, med lite över 1% i det största fallet. Det drogs slutsatsen att konceptet av areal reduction genom molnrörelse verkar vara korrekt och skulle kunna hjälpa att förbättra sättet att modellera regn generellt, men också specifikt för skyfalls scenarier med korta varaktigheter över urbana avrinningsområden. Man kom ytterligare till slutsatsen att framtida studier i samband med de fysiska processerna i regnceller skulle kunna användas för att höja noggrannheten av ytreducering av nederbörd för mer realistiska hydrauliska modeller, som i sin tur kunde minska överdesign.

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Jin, Jing. "INTEGRATING GIS AND HYDROLOGIC MODELING FOR LAND USE BASED FLOOD SIMULATION - A CASE STUDY OF MILL CREEK WATERSHED, SOUTHWEST OHIO." University of Cincinnati / OhioLINK, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=ucin987521513.

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Boldrin, Rodrigo Süzes. "Avaliação de cenários de inundações urbanas a partir de medidas não-estruturais de controle: trecho da bacia do córrego do Gregório, São Carlos - SP." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-09032016-164031/.

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Os processos de cheias em bacias urbanas vêm sendo agravados devido a uma série de motivos associados à ocupação desordenada do solo urbano. As medidas de controle de enchentes podem ter sua eficiência analisada através da modelagem hidrológica matemática. É neste sentido que o presente trabalho analisa a influência da urbanização sobre os distúrbios no escoamento superficial, por meio de simulações de cenários urbanísticos propostos, com a finalidade de servir como ferramenta de planejamento urbano. Para isso, definiu-se como área de estudo, parte da bacia do Córrego do Gregório, São Carlos - SP. As principais informações da bacia a serem consideradas são: topografia, hidrografia, uso do solo urbano, expansão da área urbana, áreas de proteção ambiental e divisores de microbacias. O modelo hidrológico utilizado é o IPHS-1, do tipo concentrado. Para essa análise são propostos e simulados cenários urbanísticos, baseados na adoção de medidas de controle de inundações não-estruturais, referindo-se principalmente, à conservação de áreas verdes e disciplinamento do uso e ocupação do solo, verificando sua eficiência na redução do volume escoado e atenuação das vazões de pico.
The flooding processes in urban basins have become worse due to many reasons. All of them associated with the disorganized occupancy of the urban area land. The efficiency of flood mitigation measures can be analyzed by mathematical modeling. This study aims to be used as a tool for urban planning and it analyses the influence of the urbanization processes on surface runoff, using simulation of several urbanization scenarios. The case study was undertaken at the Gregório River Basin in São Carlos - SP. The main information considered was topography, hydrology, urban land use, urbanization, protected land and sub-basins. The software used was IPHS-1 which is a lumped hydrologic model. In this research many urbanization scenarios are proposed and simulated. These views are based in many nonstructural flood mitigation alternatives such as land cover conservation, use and occupancy of the land, in order to check their efficiency in reducing the total volume of surface runoff and the peak flow.

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Pontremolez, Nataska Schincariol. "Estudo das inundações em cenários alternativos de uso e ocupação do solo na bacia hidrográfica do Córrego do Mineirinho em São Carlos, SP." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-27082014-110840/.

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No Brasil, o processo de urbanização iniciado na década de 1950 ocorreu sem o planejamento adequado, e resultou em impactos sobre os sistemas de drenagem das bacias hidrográficas. Essas alterações no escoamento, associadas à ocupação humana das áreas de várzea, resultam em inundações com enormes prejuízos materiais e não materiais. Na falta de uma visão mais global dos processos que ocorrem na bacia, muitas vezes os problemas de enchentes urbanas são combatidos com obras que visam expulsar a água o mais rápido possível. Tais soluções acabam por transferir o problema para regiões à jusante da bacia, além de estimular a ampliação da ocupação das planícies de inundação dos cursos de água. Em 1945, em sua tese de doutorado, o pesquisador Gilbert F. White analisou os prejuízos materiais e não materiais causados por inundações nos Estados Unidos e concluiu que, sempre que possível, a ocupação humana deve se adaptar às enchentes. A partir desse princípio, foi criado em 1969 o Urban Drainage and Flood Control District (UDFCD), com o objetivo de ajudar governos locais da região metropolitana de Denver, nos EUA, na redução do risco de inundações. O presente trabalho teve como objetivo principal o estudo das inundações geradas por precipitações de diferentes tempos de retorno em cenários alternativos de ocupação da bacia hidrográfica do Córrego do Mineirinho. Um dos cenários estudados foi desenvolvido à luz dos princípios e diretrizes do UDFCD para o controle de inundações. A modelação hidráulico-hidrológica foi utilizada para construir hidrogramas de cheia e manchas de inundação para a bacia, e assim possibilitar a comparação entre os cenários alternativos. Os resultados demonstraram que o Plano Diretor Municipal de São Carlos não considera o controle de inundações, e caso a região se desenvolva segundo suas diretrizes, ocorrerá ampliação das inundações na bacia e aumento nas vazões descarregadas no exutório, em relação à situação atual. Caso seja construído o reservatório de detenção previsto no Plano Diretor de Drenagem Urbana, as vazões no exutório diminuirão drasticamente, reduzindo o impacto nas bacias à jusante; no entanto, a inundação atingirá áreas residenciais, causando problemas aos habitantes. Caso a região se desenvolva segundo os princípios e diretrizes do UDFCD para o controle de inundações, as vazões no exutório da bacia diminuirão em relação à situação atual, e as áreas inundadas não atingirão a população.
In Brazil, the urbanization process started in the 1950s occurred without proper planning, and resulted in negative impacts on the hydrologic systems, such as increased frequency of flooding and peak flow volumes. The changes in runoff associated with human occupation of floodplains result in floods with huge losses. In the absence of a more global view of the processes occurring in the watersheds, often the problems of urban flooding are countered with works that aim to expel the water as quickly as possible. Such solutions end up transferring the problem to regions downstream of the watershed, and stimulate the occupation of floodplains. In 1945, Gilbert F. White analyzed the material and non-material damage caused by floods in the United States and concluded that whenever possible, human occupation must adapt to floods. From that idea, in 1969 was created the Urban Drainage and Flood Control District (UDFCD), with the goal of helping local governments in Denver metropolitan area, USA, in reducing the risk of flooding. This work aimed to study the floods generated by rainfall of different return periods under alternative scenarios for the land use and occupation of the watershed of stream Mineirinho, in Sao Carlos, SP. A particular scenario of land use and occupation was developed under the principles and guidelines of UDFCD for flood control. Hydraulic-hydrological modeling was performed to construct hydrographs and flood maps for the watershed, enabling a comparison between the alternative scenarios. The results demonstrated that the Master Plan of Sao Carlos does not consider flood control, and if the region is developed according to their guidelines, the flow rate and flood areas will be increase, in comparison to the current situation of land use and occupation. If the detention reservoir provided for Master Plan for Urban Drainage is built, flow rates will decrease drastically, reducing the impact on the watersheds downstream. However, the flood will reach residential areas, causing problems for the population. If the region is developed according to the principles and guidelines of UDFCD for flood control, the outflow will decrease compared to the current situation, and the flooded areas will not reach the population.

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Rubinato, Matteo. "Physical scale modelling of urban flood systems." Thesis, University of Sheffield, 2015. http://etheses.whiterose.ac.uk/9270/.

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Urban flooding is defined as ‘an overflowing or irruption of water over urban pathways which are not usually submerged’. Current economic, climatic and social trends suggest that the frequency, magnitude and cost of flooding are likely to increase in the future. Hydraulic models are commonly used by engineers in order to predict and mitigate flood risk. However full scale calibration and validation datasets for these modelling tools are scarce. The main research objective of this thesis was to design and construct a physical model in order to provide datasets useful to verify, calibrate and validate computer model results in terms of energy losses in manholes. To address these issues, an experimental facility has been constructed to enable the investigation of energy losses under steady and unsteady flow conditions in a scaled sewer system. Originally the model was composed of six manholes and three main pipes and then it was modified into a single pipe linked to an urban surface through a single manhole. Experiments involved the measurement of flow rates, velocity, pressure and water depth within the physical models under different hydraulic scenarios. Steady flow tests were conducted to quantify energy losses though manhole structures with different inlet/outlet configurations under a range of hydraulic conditions. Unsteady flow tests were conducted to examine the performance of different computational hydraulic models. These tests have shown that the performance of the SWMM hydraulic model could be improved by including local losses in the calibration process. After modification the model was used to quantify sewer to surface and surface to sewer flow exchange through a single manhole during pluvial flooding. The work has demonstrated the feasibility of using weir and orifice equations within modelling tools to quantify this exchange under steady conditions. The model was used to empirically quantify discharge coefficients for energy loss equations which describe flow exchange for the first time.

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Evans, Barry. "A multilayered approach to two-dimensional urban flood modelling." Thesis, University of Exeter, 2010. http://hdl.handle.net/10036/117891.

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With urbanisation continuing to encroach upon flood plains, the constant replacement of permeable land with impermeable surfaces and with the changes in global climate, the need for improved flood modelling is ever more apparent. A wide range of methods exist that simulate surface flow; most commonly in one-dimensional (1D) or twodimensional (2D), and more recently on smaller scales in three-dimensional (3D) models. In urban flood modelling, 2D models are often the preferred choice as they can simulate surface flow more accurately than their 1D model counterparts; they are, however, more computationally demanding and thereby usually require greater simulation time. With the vast amount of information used in flood modelling, generalisation techniques are often employed to reduce the computational load within a simulation. The objective of this thesis is to improve 2D flood modelling in urban environments by introducing a new and novel approach of representing fine scale building features within coarse grids. This is achieved by creating an automated approach that data-mines key features such as buildings and represents their effects numerically within a multiple layer grid format. This new approach is tested in comparison to two other, already established generalising techniques which are single layer based. The effectiveness of each model is assessed by its ability to accurately represent surface flow at different grid resolutions and how each copes with varying building orientations and distributions within the test datasets. The performance of each generalising approach is determined therefore by its accuracy in relation to the fine scale model and the difference in the computational time required complete the simulation. Finally the multilayered methodology is applied to a real case scenario to test its applicability further. Overall it revealed, as predicted, that the multilayered approach enables far greater accuracies at routing surface flow within coarse grids whilst still greatly reducing computational time. As a further benefit in urban flood modelling, this thesis shows that using a multilayered data format it is possible to simulate the influence of features that have a grid resolution finer than the initial terrain topology data, thus enabling, for example, the routing of surface water through alleyways between buildings that have a width less than one meter.

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Schück, Fredrik. "Implementation of Citizens’ Observations in Urban Pluvial Flood Modelling." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-297552.

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Damages caused by urban pluvial floods are believed to increase due to climate change and urbanization as more citizens are impacted in densely populated cities and extreme rainfalls occur more frequently with higher intensities. To prepare cities for these calamities, urban pluvial flood models are created to provide knowledge about how an extreme rainfall event could inundate the studied city. However, due to the scarcity of observation data from these rainfall events, flood models are seldom calibrated which is necessary to ensure their accuracy. To improve the feasibility of calibrations an emerging data source was tested, crowdsourced images from citizens. Citizens’ observations have become increasingly available due to the increase of mobile phones and the development of social media enabling citizens to document and upload their observations to the public. Researchers could use these observations as an unconventional data source to calibrate models and reduce the knowledge gap regarding urban floods. The aim of this study was to explore and increase our understanding of how citizen’s observations can be used to calibrate an urban pluvial flood model. A case study about the cloudburst event in Malmö was conducted to study this topic. During that event, more than 100 mm of rain fell over a period of 6 hours in the city and caused 60 million euros of damages. A total of 297 images depicting the flood caused by the cloudburst event were gathered from social media platforms, newspapers archives, and by inquiring citizens. Images were screened and analysed: water levels were estimated in 66 images and were then used to calibrate a 2D flood model. Furthermore, a sensitivity analysis of the calibrated results was conducted by calculating the RMSE for different subsets and compare it with the RMSE for the full dataset of citizens’ observations. This was done to study how different characteristics, such as timestamp and source as well as sample size and location of the images influences the calibration procedure. After the model was calibrated, the importance of spatial variability in the rainfall input was tested by comparing the flood model output between the spatially varied observed rainfall and a Chicago Design Storm rainfall, which lacks spatial variability. It was concluded that images from citizens can be used to calibrate an urban pluvial flood model, but the procedure is time-consuming. However, it was also evident that images directly inquired from citizens reduced the time needed as their local knowledge could be integrated. The calibration procedure was also sensitive to the quality of the observations, especially when the images were photographed in relation to the rainfall event. Even though the study had limitations it demonstrates new possibilities to calibrate urban pluvial flood models.
Konsekvenserna av översvämningar från skyfall i städer, så kallade pluviala översvämningar, förväntas öka på grund av urbanisering och klimatförändringar. Det är för att fler påverkas av översvämningar i tätbyggda städer samt att skyfall förväntas öka, både i intensitet och frekvens. Med hjälp av skyfallsmodeller kan dock förståelsen för hur extrema regn översvämmar städer öka. Med denna kunskap kan åtgärder för att minimera konsekvenserna implementeras, såsom blågrön infrastruktur. Däremot finns det en brist av observationsdata från pluviala översvämningar och vilket medför att dessa modeller ytterst sällan kalibreras. Kalibrering är viktig för att säkerställa tillförlitliga modeller. För att öka möjligheten att kalibrera dessa modeller undersöktes hur observationer från medborgare kan implementeras. Dessa observationer är en relativ oprövad metod men har blivit alltmer tillgängliga tack vare allt bättre mobiltelefonkameror och utvecklingen av sociala medier, vilket gör det enkelt för medborgare att dokumentera och ladda upp sina observationer till allmänheten. Syftet med denna studie är därför att öka förståelsen för hur bilder från medborgare kan användas för att möjliggöra kalibreringen av översvämningsmodeller. En fallstudie över ett skyfall i Malmö 2014 används för att utvärdera denna metod. Under detta skyfall regnade det mer än 100 mm vilket orsakade skador för cirka 600 miljoner kronor. Totalt samlades 297 bilder som föreställde översvämningen som orsakades av skyfallet. Bilderna samlades ifrån sociala media, tidningsbildarkiv och genom att fråga medborgare efter bilder. Vattennivåerna uppskattades i 66 bilder och de användes sedan för att kalibrera en 2D- skyfallsmodell. Utöver kalibreringen genomfördes en känslighetsanalys av de kalibrerade resultaten genom att jämföra medelfelet för olika subgrupper av bilderna mot medelfelet för alla bilder. Detta gjordes för att studera hur olika egenskaper, såsom när bilden togs och deras ursprung samt bildernas urvalsstorlek och placering påverkar kalibreringsprocessen. Efter att modellen kalibrerats testades också betydelsen av spatial variation i nederbörden genom att jämföra de simulerade vattennivåerna mellan den spatialt varierade historiska regnet och ett syntetiskt CDS-regn som saknar variation. Utifrån det drogs slutsatsen att bilder från medborgare kan användas för att kalibrera en skyfallsmodell, men metoden är tidskrävande. Dock var det tydligt att bilder som direkt efterfrågades från medborgarna minskade arbetsbördan då deras lokalkännedom kunde inkluderas. Kalibreringen var också känslig för observationerna datakvalitet, särskilt när bilderna fotograferades i förhållande till regnet. Även om studien hade begränsningar visar den att det finns stora möjligheter att kalibrera skyfallsmodeller med observationer från medborgare.

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Forrest, Simon John. "The Use of High Resolution Precipitation Data in Urban Flood Modelling." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017.

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Urban area studies have concentrated on the records of rain and water level gauges to predict the hydrological response and potential flooding. High resolution data is needed in Urban Areas as it may reduce the risk of potential flooding, especially rapid and local events.

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Eriksson, Johanna. "Sensitivity analysis of pluvial flood modelling tools for dense urban areas : A case study in Lundby-Lindholmen, Gothenburg." Thesis, Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-80431.

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As a result of the global climate change, extreme precipitation is occurring more frequently which increases the risk of flooding, especially in urban areas. Urbanisation is widely discussed regarding urban flooding where an increase of impervious surfaces limits the infiltration and increases the surface runoff. Flooding events in urban areas are increasing around the world and can cause large damages on infrastructure and buildings, which makes the cities vulnerable. Urban flood models are an important tool for analysing the capacity of the drainage systems, to predict the extent of the events and to find optimal locations to implement measures to prevent damages from flooding. In this project, a sensitivity analysis in MIKE FLOOD, a coupled 1D-2D flood model developed by DHI is presented, where sewer- and surface systems are integrated. The aim with this project is to investigate how the result of a coupled flood model vary in relation to changes in input parameters. The sensitivity analysis is performed to evaluate how different parameters impact the model output in terms of water depth and variations in cost of flooded buildings, roads, rail- and tramways. The analysis is applied in a case study in Lundby-Lindholmen, Gothenburg city, Sweden. The results show that modelling without infiltration influenced the model output the most, with the largest increase both in terms of cost and water depth over the investigated area. Here the correlation between the initial water saturation and location of the applied pre-rain was highlighted. The model outputs were less sensitive to changes in surface roughness (expressed as Manning value) than without infiltration but did lead to measurable changes in surface water depth and distribution while the flood damage cost didn’t show any major changes. Additionally, the coupled flood model was evaluated in terms of handling changes in magnitudes of rain-events. Data indicates the shorter the return period, the smaller the flood propagation, as well as the flood damage cost decreases with shorter return periods. The data evaluated supports the use of this coupled model approach for shorter return periods in terms of flood propagation.

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Leandro, Jorge. "Advanced modelling of flooding in urban areas : integrated 1D/1D and 1D/2D models." Thesis, University of Exeter, 2008. http://hdl.handle.net/10036/41949.

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The research presented in this Thesis aims at defining the strengths and weaknesses of an Improved 1D/1D model when compared with a more accurate 1D/2D model. Although both coupled-models (sewer/surface) solve the St.\ Venant equations in both layers, the latter uses a higher approximation (2D two-dimensional) on the surface layer. Consequently, the 1D/1D model is computationally more efficient when compared to the 1D/2D model, however there is some compromise with the overall accuracy. The hypothesis is that "The inundation extent of urban flooding can be reproduced by 1D/1D models in good agreement with the 1D/2D models if the results are kept within certain limits of resolution and under certain conditions". The Thesis starts by investigating ways of improving an existing 1D/1D model to rival the more accurate 1D/2D model. Parts of the 1D/1D model code are changed and new algorithms and routines implemented. An innovative GIS tool translates the 1D output-results into 2D flood-inundation-maps enabling a thorough comparison between the two models. The methodology assures the set-up of two equivalent models, which includes a novel algorithm for calibrating the 1D/1D model vs.\ the 1D/2D model results. Developments are tested in two distinctly different case studies of areas prone to flooding. The conclusion is that the 1D/1D model is able to simulate flooding in good agreement with the 1D/2D model; however, it is found that features such as topography, density of the urbanised areas and rainfall distribution may affect the agreement between both models. The work presented herein is a step forward in understanding the modelling capabilities of the analysed coupled-models, and to some extent may be extrapolated to other models. Research is growing in urban flooding and this work may well prove to be a strong foundation basis for future research.

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Kharat, Deepak Bhimrao. "Practical aspects of integrated 1D2D flood modelling of urban floodplains using LiDAR topography data." Thesis, Heriot-Watt University, 2009. http://hdl.handle.net/10399/2272.

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Flood risk, a major risk facing mankind today, is projected to aggravate in view of the future predictions pertaining to the assessment of climate change scenarios. Traditionally, flood risk assessment exercises of urban floodplains have been carried out using 1D model as well as 1D model with storage cells. In view of the recent availability of high quality Light Detection and Ranging (LiDAR) topography data, availability of higher computing capacities, developments in the numerical computing techniques and the merits of an integrated 1D2D computing modelling method, integrated 1D2D modelling has gained a momentum for strategic flood risk management (SFRM) and detailed urban flood risk analysis. The research discussed in this thesis evaluates this modelling method using high quality LiDAR data in light of the results from the traditionally used 1D model with storage cells modelling method. The research study was carried out using laboratory experimental observation data, hypothetical urban floodplain data and data for a section of the River Clyde and adjoining urban floodplain in Glasgow, a major city in Scotland, UK. It concludes that, while integrated 1D2D models are of much benefit for a detailed flood risk analysis, specific attention needs to be paid towards the lateral extents of 1D model and the source of the river bank elevations while integrating it with a 2D model, particularly so when such a study is carried out for urban floodplains; and that the high quality LiDAR data significantly facilitates Strategic Flood Risk Modelling (SRFM) of urban floodplains.

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Andersson, Evelina. "Flood modelling in urban areas : A comparative study of MIKE 21 and SCALGO Live." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-300466.

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Pluvial flooding originating from extreme rainfall is problematic and an increasing issue in Sweden. Higher requirements on adapting cities in urban areas to these challenges have been placed on both municipalities and the county administration. Thus, an increased need for water modelling, both in existing and planned areas have emerged. The Danish Hydrological Institute (DHI) has developed several models and tools to simulate floods and heavy rains, of which MIKE 21 is one. MIKE 21 is a dynamic model consisting of hydrological calculations in each cell, requiring modelling skills and long simulation time, but is proven to be a good and credible model. SCALGO Live, on the other hand, is a static tool simulated by raster-based algorithms and capable of giving fast results directly on the platform. However, compared to MIKE 21, SCALGO Live is not as evaluated nor is its use as widespread for simulating floods and heavy rain events. This study aims to investigate how inundation in twenty urban areas caused by cloudbursts is simulated in both programs to examine how well the result coming from SCALGO Live, is equivalent to the result from the MIKE 21-model. The comparison is made in both depth and spread using three comparative indexes, two statistical equations and one map, showing the extension of the inundation in both models. To make the models comparable, the model in MIKE 21 is made as equivalent as possible with SCALGO Live before simulation and the purpose is to investigate whether there is any type of area where the two different models are equivalent. The result shows that the flooded areas from SCALGO Live are in good agreement in most areas with the MIKE 21-model, but that the depth in the depression zones is somewhat overestimated, compared with the highest value in MIKE 21. The MIKE 21-model has a greater spread upstream, showing flowpaths if compared directly with the flooded areas from SCALGO Live, but if activating the flow accumulation tool in SCALGO Live, the differences are reduced but cannot be quantified in this study. The differences between the models increase with a higher resolution, longer flowpaths and a larger catchment, at least for the confined catchments. To conclude, SCALGO Live is best suited for smaller confined catchments where there are no long or complex flowpaths. SCALGO Live also works well at an early stage in the planning process and as a platform for combining detailed data and results. However, for the more complex areas, MIKE 21 is better suited, since various parameters can be considered.

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Mousavi, Moghaddam Seyedali. "Inundation mapping of urban areas in case of severe rainfall events using HEC-RAS." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.

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The current study investigates the potential of HEC-RAS (2D) in simulating urban inundation patterns in case of sever rainfall scenarios expected in the Ferrara and Rimini cities in Italy. HEC-RAS is one to most known and used hydraulic model for river application, however, its rainfall module is relatively new and sparsely investigated. Comparison of different mesh sizes (10, 25 and 50m) indicated no significant difference in model performance. However, a significant difference was observed in simulation time. Inundation maps were obtained for 5, 20 and 100-year rainfall events. HEC-RAS model outputs are compared against ground evidence and detailed outputs obtained with other modelling scheme: filling-and-spilling algorithm and a two-dimensional (2D) hydraulic numerical model (jn Rimini). For both Ferrara and Rimini case studies, overall index of agreement between HEC-RAS and filling-and-spilling models is up to 88%, while the similarity (i.e., flood area index) between HEC-RAS and 2D hydraulic model simulation at Rimini is equal to 0.64. In general, this study provides addition insights concerning HEC-RAS potential and limitations for identifying pluvial flood-hazard spots across large urban environments.

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Mugume, Seith Ncwanga. "Modelling and resilience-based evaluation of urban drainage and flood management systems for future cities." Thesis, University of Exeter, 2015. http://hdl.handle.net/10871/18870.

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In future cities, urban drainage and flood management systems should be designed not only to reliable during normal operating conditions but also to be resilient to exceptional threats that lead to catastrophic failure impacts and consequences. Resilience can potentially be built into urban drainage systems by implementing a range of strategies, for example by embedding redundancy and flexibility in system design or rehabilitation to increase their ability to efficiently maintain acceptable customer flood protection service levels during and after occurrence of failure or through installation of equipment that enhances customer preparedness for extreme events or service disruptions. However, operationalisation of resilience in urban flood management is still constrained by lack of suitable quantitative evaluation methods. Existing hydraulic reliability-based approaches tend to focus on quantifying functional failure caused by extreme rainfall or increases in dry weather flows that lead to hydraulic overloading of the system. Such approaches take a narrow view of functional resilience and fail to explore the full system failure scenario space due to exclusion of internal system failures such as equipment malfunction, sewer (link) collapse and blockage that also contribute significantly to urban flooding. In this research, a new analytical approach based on Global Resilience Analysis (GRA) is investigated and applied to systematically evaluate the performance of an urban drainage system (UDS) when subjected to a wide range of both functional and structural failure scenarios resulting from extreme rainfall and pseudo random cumulative link failure respectively. Failure envelopes, which represent the resulting loss of system functionality (impacts) are determined by computing the upper and lower limits of the simulation results for total flood volume (failure magnitude) and average flood duration (failure duration) at each considered failure level. A new resilience index is developed and applied to link resulting loss of functionality magnitude and duration to system residual functionality (head room) at each considered failure level. With this approach, resilience has been tested and characterized for a synthetic UDS and for an existing UDS in Kampala city, Uganda. In addition, the approach has been applied to quantify the impact of interventions (adaptation strategies) on enhancement of global UDS resilience to flooding. The developed GRA method provides a systematic and computationally efficient approach that enables evaluation of whole system resilience, where resilience concerns ‘beyond failure’ magnitude and duration, without prior knowledge of threat occurrence probabilities. The study results obtained by applying the developed method to the case studies suggest that by embedding the cost of failure in resilience-based evaluation, adaptation strategies which enhance system flexibility properties such as distributed storage and improved asset management are more cost-effective over the service life of UDSs.

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Leitao, Joao Paulo Correia. "Enhancement of digital elevation models and overland flow path delineation methods for advanced urban flood modelling." Thesis, Imperial College London, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.508782.

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The objective of this thesis is to improve existing and develop new DEM enhancement methods and DEM-based overland flow delineation methods in order to generate reliable overland flow networks. These networks can be used in conjunction with existing urban drainage modelling methodologies in order to improve surface flooding simulation results. The objective has been achieved by: developing new methods to merge DEMs; evaluating nad improving available DEM enhancement methods; improving methods to solve DEM flat area problems, and developing novel methods to improve overland flow path delineation. All improvements and new developments have been adapted to the specific characteristics of high-resolution DEMs and urban catchments. The experimental work undertaken in Lisbon, together with two case-studies in the UK, was used to validate the concepts proposed in this thesis. It is concluded that DEM enhancement methods can be used to improve DEMs for overland flow delineation, thereby enhancing the reliability of urban flood modelling. The advanced flow path delineation methods developed here produce more reliable results than conventional overland flow path delineation methods. The hydraulic simulation results obtained confirm the advantages of applying 1D/1D modelling to simulate urban flood events. However, the findings show that the use of these methods needs to be preceded by a thorough analysis and quantification of Dem surface characteristics, and by a detailed calibration and validation procedure. Independent testing carried out by UKWIR has proved the adequacy and reliability of the developed methodology in full scale flood risk mapping applications.

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Green, Daniel. "Understanding urban rainfall-runoff responses using physical and numerical modelling approaches." Thesis, Loughborough University, 2018. https://dspace.lboro.ac.uk/2134/33530.

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This thesis provides a novel investigation into rainfall-runoff processes occurring within a unique two-tiered depth-driven overland flow physical modelling environment, as well as within a numerical model context where parameterisation and DEM/building resolution influences have been investigated using an innovative de-coupled methodology. Two approaches to simulating urban rainfall-runoff responses were used. Firstly, a novel, 9 m2 physical modelling environment consisting of a: (i) a low-cost rainfall simulator component able to simulate consistent, uniformly distributed rainfall events of varying duration and intensity, and; (ii) a modular plot surface layer was used. Secondly, a numerical hydroinundation model (FloodMap2D-HydroInundation) was used to simulate a short-duration, high intensity surface water flood event (28th June 2012, Loughborough University campus). The physical model showed sensitivities to a number of meteorological and terrestrial factors. Results demonstrated intuitive model sensitivity to increasing the intensity and duration of rainfall, resulting in higher peak discharges and larger outflow volumes at the model outflow unit, as well as increases in the water depth within the physical model plot surface. Increases in percentage permeability were also shown to alter outflow flood hydrograph shape, volume, magnitude and timing due to storages within the physical model plot. Thus, a reduction in the overall volume of water received at the outflow hydrograph and a decrease in the peak of the flood event was observed with an increase in permeability coverage. Increases in the density of buildings resulted in a more rapid receding limb of the hydrograph and a steeper rising limb, suggesting a more rapid hydrological response. This indicates that buildings can have a channelling influence on surface water flows as well as a blockage effect. The layout and distribution of permeable elements was also shown to affect the rainfall-runoff response recorded at the model outflow, with downstream concentrated permeability resulting in statistically different hydrograph outflow data, but the layout of buildings was not seen to result in significant changes to the outflow flood hydrographs; outflow hydrographs appeared to only be influenced by the actual quantity and density of buildings, rather than their spatial distribution and placement within the catchment. Parameterisation of hydraulic (roughness) and hydrological (drainage rate, infiltration and evapotranspiration) model variables, and the influence of mesh resolution of elevation and building elements on surface water inundation outputs, both at the global and local level, were studied. Further, the viability of crowdsourced approaches to provide external model validation data in conjunction with dGPS water depth data was assessed. Parameterisation demonstrated that drainage rate changes within the expected range of parameter values resulted in considerable losses from the numerical model domain at global and local scales. Further, the model was also shown to be moderately sensitive to hydraulic conductivity and roughness parameterisation at both scales of analysis. Conversely, the parameterisation of evapotranspiration demonstrated that the model was largely insensitive to any changes of evapotranspiration rates at the global and local scales. Detailed analyses at the hotspot level were critical to calibrate and validate the numerical model, as well as allowing small-scale variations to be understood using at-a-point hydrograph assessments. A localised analysis was shown to be especially important to identify the effects of resolution changes in the DEM and buildings which were shown to be spatially dependent on the density, presence, size and geometry of buildings within the study site. The resolution of the topographic elements of a DEM were also shown to be crucial in altering the flood characteristics at the global and localised hotspot levels. A novel de-coupled investigation of the elevation and building components of the DEM in a strategic matrix of scenarios was used to understand the independent influence of building and topographic mesh resolution effects on surface water flood outputs. Notably, the inclusion of buildings on a DEM surface was shown to have a considerable influence on the distribution of flood waters through time (regardless of resolution), with the exclusion of buildings from the DEM grid being shown to produce less accurate results than altering the overall resolution of the horizontal DEM grid cells. This suggests that future surface water flood studies should focus on the inclusion and representation of buildings and structural features present on the DEM surface as these have a crucial role in modifying rainfall-runoff responses. Focus on building representation was shown to be more vital than concentrating on advances in the horizontal resolution of the grid cells which make up a DEM, as a DEM resolution of 2 m was shown to be sufficiently detailed to conduct the urban surface water flood modelling undertaken, supporting previous inundation research.

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Bouchenafa, Walid. "Modélisation des inondations en tunnel en cas de crue de la Seine pour le Plan de Protection des Risques Inondations de la RATP (PPRI)." Thesis, Compiègne, 2017. http://www.theses.fr/2017COMP2338/document.

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La crue de 1910 de la Seine a eu une incidence directe sur le fonctionnement des différents réseaux (réseau électrique, assainissement des eaux usées, transport, eau potable). Le réseau RATP a été particulièrement atteint dans son fonctionnement. Les dommages qu’une crue centennale pourrait engendrer aujourd’hui risquent d’être plus importants encore car le réseau actuel est plus vulnérable du fait des nombreux équipements électriques et informatiques qu’il comporte. La majorité des émergences (les entrées d’eau) de la RATP est située en zone inondable. Lors d’une crue majeure de la Seine, les écoulements dus aux inondations se propagent directement dans la partie souterraine et centrale du réseau (Métro et RER) par le biais de ces émergences. Cette thèse s'intéresse à la simulation hydrodynamique des écoulements dans le réseau RATP en utilisant le logiciel MIKE URBAN dédié à la modélisation des réseaux d’assainissement. Cette modélisation nécessite une bonne connaissance de l’origine des écoulements pour mieux les prendre en compte. En effet, le réseau RATP est inondé par les eaux superficielles et les eaux d’infiltration. Afin de mieux quantifier les volumes entrants dans le réseau, un modèle physique d’une bouche de métro type a été réalisé. Les résultats des essais physiques ont permis de valider un modèle numérique qui caractérise les écoulements autour d’une bouche de métro et quantifie les volumes entrants. Cela a permis également de proposer une formule théorique de débit tenant compte de la géométrie d’une bouche de métro. Les écoulements par infiltration sont quant à eux modélisés en fonction de la charge de la nappe et validés avec des mesures in situ. Ce travail de recherche a comme objectif d’améliorer et valider un modèle de simulation. Il s’agit de mettre en œuvre un outil opérationnel d’aide à la décision qui permettra à la cellule inondation de la RATP de bien comprendre le fonctionnement de son réseau afin d’améliorer son plan de protection contre le risque inondation
The 1910 flood of the Seine had a direct impact on the functioning of the different networks (Electricity network, sewerage, transport, water distribution). The RATP network was particularly affected in its functioning. The damage that centennial flood could cause today may be even greater because the current network is more vulnerable because of the numerous electrical and computer equipment that it comprises. The majority of the emergences (The water ingress) of the RATP is located in flood areas. During a major flooding of the Seine, the flows due to the floods propagate directly into the underground and central part of the network (Metro and RER) through these emergences. This thesis is interested in a hydrodynamic simulation by MIKE URBAN, Model used to model the RATP network due to its MOUSE engine developed by DHI for the sewerage networks. This work also presents the results obtained on a physical model of a subway station. The experimental data were used to model water ingress within the RATP network from the subway station. Network protection against infiltration requires a thorough knowledge of underground flow conditions. Infiltrations through the tunnels are estimated numerically. The aim of this research is to improve and validate a simulation model. It is a question of implementing an operational decision support tool which will allow the flood cell of the RATP to understand the functioning of its network in order to improve its flood risk protection plan

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Olsson, Jimmy. "The influence of storm movement and temporal variability of rainfall on urban pluvial flooding : 1D-2D modelling with empirical hyetographs and CDS-rain." Thesis, Uppsala universitet, Luft-, vatten och landskapslära, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-387898.

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Pluvial floods are formed directly from surface runoff after extreme rain events. Urban areas are prone to suffer from these floods due to large portions of hardened surfaces and limited capacity in the stormwater infrastructure. Previous research has shown that catchment response is influenced by the spatio-temporal behaviour of the rainstorm. A rainstorm moving in the same direction as the surface flow can amplify the runoff peak and temporal variability of rainfall intensity generally results in greater peak discharge compared to constant rainfall. This research attempted to relate the effect of storm movement on flood propagation in urban pluvial flooding to the effect from different distributions of rainfall intensity. An additional objective was to investigate the flood response from recent findings on the temporal variability in Swedish rain events and compare it to the flood depths produced by a CDS-rain (Chicago Design Storm), where the latter is the design practice in flood modelling today. A 2D surface model of an urban catchment was coupled with a 1D model of the drainage network and forced by six different hyetographs. Among them were five empirical hyetographs developed by Olsson et al. (2017) and one a CDS-rain. The rainstorms were simulated to move in different directions: along and against the surface flow direction, perpendicular to it and with no movement. Maximum flood depth was evaluated at ten locations and the model results show that storm movement had negligible effect on the flood depths. The impact from the movement was likely limited by the big difference in speed between the rainstorm and the surface flow. All evaluated locations showed a considerable sensitivity to changes in the hyetograph. The maximum flood depth increased at most with a factor of 1.9 depending on the hyetograph that was used as model input. The CDS-rain produced higher flood depths compared to the empirical hyetographs, although one of the empirical hyetographs produced a similar result. Based on the results from this case study, it was concluded that storm movement was not as critical as the temporal variability of rainfall when evaluating maximum flood depth.
Pluviala översvämningar skapas från ytavrinning vid intensiva nederbördstillfällen. De uppstår ofta i urbana miljöer till följd av den höga andelen hårdgjorda ytor och ledningsnätets begränsade kapacitet. Forskning har visat att ett regnmolns rörelseriktning och hastighet påverkar avrinningsförloppet. Om molnet rör sig längs med flödesriktningen i terrängen kan en ökning i vattenlödet nedströms ett avrinningsområde uppstå. Denna effekt har visat sig vara störst om hastigheten hos regnmolnet och vattenflödet är likvärdiga. Ytterliggare en faktor som påverkar avrinningsförloppet är hur regnintensiteten är fördelad över tid. Olsson et al. (2017) har tagit fram fem empiriska regntyper som speglar tidsfördelning inom ett Svenskt regntillfälle. Inom översvämningsmodellering är det vanligt att använda ett så kallat CDS-regn (Chicago Design Storm), vilken har en given tidsfördelning. Med anledning av detta är det intressant att jämföra översvämningar genererade av ett CDS-regn och av de empiriska regntyperna. Syftet med denna studie var att utreda hur regnmolns rörelse påverkar urbana pluviala översvämningar med avseende på vattendjup, samt att jämföra denna påverkan med effekten från olika tidsfördelningar av regnintensiteter. En kombinerad dagvattenmodell (1D) och markavrinningsmodell (2D) av en mindre svensk tätort användes för att simulera olika regnscenarier. De fem empiriska regntyperna och ett CDS-regn simulerades med en rörelseriktning längs med, emot och vinkelrätt i förhållande till flödesriktningen. Även scenarier med stationära regnmoln simulerades. Maximala översvämningsdjup utvärderades i tio punkter spridda över hela modellområdet. Resultatet från simuleringarna visade att regnmolnets rörelse hade försumbar påverkan på översvämningsdjupen. De olika tidsfördelningarna av regnintensitet hade däremot betydande påverkan på de maximala översvämningsdjupen. Som mest var det det maximala översvämningsdjupet 1.9 gånger större beroende vilken regntyp som användes som indata. CDS-regnet genererade i regel de största översvämningsdjupen, även om utfallet från en av de fem empiriska regntyperna var förhållandevis likvärdigt. Regnintensitetens tidsfördelning var därmed en kritisk parameter vid den hydrauliska modelleringen av urbana pluviala översävmningar, till skillnad från molnrörelse som hade försumbar påverkan.

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Felizardo, Lucas Menezes [UNESP]. "Aplicação de Sistema de Informações Geográficas (SIG) para modelagem de eventos críticos de vazão em uma microbacia urbana." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/144450.

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Com o aumento da população mundial e com sua concentração cada vez maior no meio urbano uma gama de problemas vem se apresentando relacionado a esse aumento populacional de maneira direta ou indireta, esse êxodo das pessoas para os grandes centros urbanos vem alterando o espaço geográfico desse ambiente bem rapidamente, principalmente na região do sudeste brasileiro onde os processos de industrialização são mais evidentes. Com essa migração a ocupação e o uso do solo vêm sendo ocupada nem sempre da forma que os planos diretores das cidades recomendam proporcionando na maioria dos casos impactos negativos nos recursos naturais. As alterações antrópicas realizadas nessas áreas, como desmatamento e a urbanização, estão promovendo um desequilíbrio ao meio ambiente afetando áreas drenadas pelas bacias hidrográficas, a complexidade do ambiente urbano e de sua infraestrutura de drenagem tem uma influência inerente no escoamento superficial, este escoamento gera inundações urbanas, que impõe desafios à modelagem, a simulação destes cenarios exigem dados detalhados de elevação. Os problemas acarretados pela ocupação desordenada da bacia vêm sendo abordados em inúmeros estudos de casos que demonstram que o uso e ocupação do solo de forma inadequada e desordenada, muitas vezes, com obras mal dimensionadas, acarretam grandes prejuízos socioeconômicos. O planejamento integrado de uma bacia urbana é o único meio de viabilizar seus usos, sem que isso acarrete em um maior desequilíbrio do meio físico, e nesse cenário que com os dados de obtidos da bacia do Córrego do Mineirinho foi feito a modelagem de cenários de eventos de precipitação e seus possíveis efeitos no meio físico com compilações e um único software. O córrego do mineirinho e outras bacias da região já vem sendo estudadas por inúmeros pesquisadores seus resultados obtidos com múltiplas ferramentas computacionais se mostram compatíveis com os que obtivemos com o uso de apenas um software para realizar todas as fases do processo desde o pré-processamento de imagens de satélite a produção de modelos em 3D de inundação de eventos de precipitação em inúmeros cenários.
With the increasing world population and its increasing concentration in urban areas a range of issues has been presented related to this population increase directly or indirectly, this exodus of people to large urban centers is changing the geographic space that environment very quickly, especially in the Brazilian southeast region where industrialization processes are most evident. With this migration the occupation and land use have been busy not always the way the master plans of cities recommend providing in most cases negative impacts on natural resources. Anthropogenic changes made in these areas, as deforestation and urbanization, are promoting an imbalance to the environment affecting the watershed drained areas, the complexity of the urban environment and its drainage infrastructure has an inherent influence on runoff, this flow generates floods urban, which poses challenges to modeling. The simulation of these scenarios require detailed elevation data. The problems posed by irregular occupation of the basin have been addressed in numerous studies that demonstrate that the use and occupation of inappropriate and disorderly manner, often with poorly scaled works, present major socioeconomic losses. Integrated planning of an urban basin is the only means of enabling their uses, without incurring a greater imbalance in the physical environment, and in this scenario with data obtained from Mineirinho Stream basin was made scenario modeling precipitation events and their potential effects on the physical environment with a unique compilations and software. The stream Mineirinho and other basins in the region has already been studied by numerous researchers their results with multiple computational tools to show compatible with those obtained using only one software to perform all phases of the process from the pre-processing satellite images to produce 3D models of flood precipitation events in many scenarios.

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Felizardo, Lucas Menezes. "Aplicação de Sistema de Informações Geográficas (SIG) para modelagem de eventos críticos de vazão em uma microbacia urbana /." Ilha Solteira, 2016. http://hdl.handle.net/11449/144450.

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Orientador: Jefferson Nascimento de Oliveira
Resumo: Com o aumento da população mundial e com sua concentração cada vez maior no meio urbano uma gama de problemas vem se apresentando relacionado a esse aumento populacional de maneira direta ou indireta, esse êxodo das pessoas para os grandes centros urbanos vem alterando o espaço geográfico desse ambiente bem rapidamente, principalmente na região do sudeste brasileiro onde os processos de industrialização são mais evidentes. Com essa migração a ocupação e o uso do solo vêm sendo ocupada nem sempre da forma que os planos diretores das cidades recomendam proporcionando na maioria dos casos impactos negativos nos recursos naturais. As alterações antrópicas realizadas nessas áreas, como desmatamento e a urbanização, estão promovendo um desequilíbrio ao meio ambiente afetando áreas drenadas pelas bacias hidrográficas, a complexidade do ambiente urbano e de sua infraestrutura de drenagem tem uma influência inerente no escoamento superficial, este escoamento gera inundações urbanas, que impõe desafios à modelagem, a simulação destes cenarios exigem dados detalhados de elevação. Os problemas acarretados pela ocupação desordenada da bacia vêm sendo abordados em inúmeros estudos de casos que demonstram que o uso e ocupação do solo de forma inadequada e desordenada, muitas vezes, com obras mal dimensionadas, acarretam grandes prejuízos socioeconômicos. O planejamento integrado de uma bacia urbana é o único meio de viabilizar seus usos, sem que isso acarrete em um maior desequilíbrio do me... (Resumo completo, clicar acesso eletrônico abaixo)
Mestre

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Friman, Jacob. "Skyfallskartering i Kumla : 2D-hydraulisk modellering och känslighetsanalys." Thesis, Uppsala universitet, Luft-, vatten och landskapslära, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-325123.

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Översvämningar till följd av intensiva nederbördstillfällen har de senaste åren ökat i antal och omfattning. Dessa händelser förväntas bli vanligare i framtiden och skapa fler översvämningar. Med anledning av detta är det intressant att undersöka hur översvämningar i framtiden breder ut sig och vilka vattennivåer som bildas med förväntad nederbörd. Att modellera översvämningar kräver data som i vissa fall kan vara både tidskrävande och omständig att införskaffa. Möjliga avgräsningar och antaganden i modellparametrar kan då vara intressanta att göra som fortfarande ger användbara resultat. En skyfallskartering har genomförts med 2D-hydraulisk modellering i Kumla med programvaran MIKE 21 Flow Model FM. De översvämningskartor som skapades användes för att identifiera områden i Kumla som riskerar att drabbas av höga vattennivåer till följd av skyfall motsvarande 100- och 200-årsregn. En stor osäkerhet vid modellering av översvämningar är att validera resultaten som fås fram. Ofta saknas information om tidigare översvämningar. De nederbördstillfällen som används är ofta så stora att det saknas data om liknande händelser tidigare. Vid översvämningsmodellering anväds data som beskriver olika typer av modellparametrar. Dessa kommer med ytterligare osäkerheter som kan göra valideringen problematisk. För att undersöka hur stor effekt olika modellparametrar har på resultatet genomfördes en känslighetsanalys där differenskartor skapades mellan undersökta scenarion och referenskartor. Skyfallskarteringen visade att stora delar i Kumla drabbas av översvämningar för både ett 100- och 200-årsregn. Området Kumlaby identifierades som känsligt och får höga vattennivåer. Detta beror mest troligt på omgivningens topografi och att Kumlaby underlagras av leror med låg infiltrationskapacitet. I känslighetsanalysen identifierades markens råhet och infiltrationskapacitet vara styrande parametrar för översvämningens utbredning och vattennivåer. Dessa påverkar främst hur höga vattenflöden som uppstår och översvämningens utbredningen och vattennivåer. Kunskap om dessa parametrar är viktigt för att undvika över- eller underskattning av en översvämning. Användningen av avrinningskoefficienter istället för markens råhet, infiltrationskapacitet och evaporation undersöktes. Differensen i översvämningens utbredning och vattennivåer blev stor i och utanför Kumla tätort. På mindre områden kan det vara mer lämpligt att använda en avrinningskoefficient när en mer detaljerad klassning kan göras av de markytor som finns. Ett scenario som undersöktes i känslighetsanalysen var installation av gröna tak på alla byggnader i Kumla. Simuleringarna som genomfördes visade att både utbredningen och vattennivåer minskade. Detta till följd av större lagringskapacitet och motstånd mot vattenflöden som kommer med gröna tak.
Urban floods caused by intense rainfall have occurred more frequently the last couple of years. These rainfall events are expected to become more common in the future and create more floods in urban areas. This makes it important to investigate the extent and water levels from urban floods in the future. In order to simulate floods, different types of data is needed. This data can be both time consuming and difficult to obtain. With this in mind, it is interesting to investigate possible simplifications and assumptions of model parameters. A cloud burst mapping was made with 2D hydraulic modelling in Kumla with the software MIKE 21 Flow Model FM. The flood maps created were used to identify areas in Kumla which have a higher risk of being subject to high water levels. One uncertainty while modelling urban floods is the process of validating the results. There is often a lack of data for the used rainfall events or information from previous floods in the area. In flood modelling data is used which describes different model parameters, these comes with additional uncertainties and can make the validation more difficult. A sensitivity analysis was made to be able to examine effects on the results from variations in model parameters. The cloud burst mapping showed that large parts of Kumla will be affected by water levels which goes up to 1 m. The area Kumlaby was identified as being sensitive for high water levels. This is due to placement of Kumlaby below higher ground which causes water to flow toward Kumlaby. The ground below is mostly made up of clay which has low infiltration capacity. In the sensitivity analysis the bed resistance and infiltration capacity were identified as governing parameters regarding the extent and water levels of urban floods. In order to avoid over- or underestimation of floods it is important to have knowledge about these parameters in the model area. The use of a runoff coefficient instead of bed resistance, infiltration and evaporation were examined. The difference of the resulting flood were large in the whole model area. In smaller areas a runoff coefficient could be used with better results when a more detailed description can be made of the surfaces in the area. A scenario where green roofs were assumed to have been installed on all buildings in Kumla were examined. The simulations showed that both the extent and water levels decreased. This due to the fact that green roofs have a capacity to store water and delay flows of water.

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Alvarez, Montero Gabriela Fiamma, and Cueva Carlos Alvaro Moreno. "Modelamiento hidráulico para el control y prevención de inundaciones mediante el uso de Hec-Ras 2d en la zona urbana del río Piura." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2021. http://hdl.handle.net/10757/656880.

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Los desastres ocasionados por las inundaciones son cada vez más comunes alrededor del mundo, tal como ocurre en la parte Occidental de América del Norte y Sur, debido a la presencia del Fenómeno “El Niño” (FEN), que provoca un aumento de las precipitaciones y caudales de los ríos provocando inundaciones. Por este motivo, en el presente trabajo se ha realizado la simulación numérica de inundación frente a eventos extremos como El Niño, con la finalidad de disminuir el área y nivel de inundación ante probables y distintos eventos en zonas cercanas a los cauces de ríos. Se ha empleado datos hidrológicos de caudales promedios y máximos instantáneos de un periodo de 40 años. Para la caracterización morfológica de la zona se ha empleado información de un modelo de elevación digital del terreno (DEM), obtenido del satélite SPOT-7, de resolución de 6x6m. La información hidrológica fue procesada mediante el método de Gumbel para obtener los caudales de simulación para periodos de retorno de 2, 5, 10, 50, 100 y 500 años. La modelación numérica fue realizada empleando HEC-RAS 5.0.7, con lo que se obtuvo el área de inundación para el FEN 2017 y se utilizó la imagen satelital SENTINEL-2 para validar el modelo. Asimismo, se modeló eventos extremos con periodos de retorno mayores a 10 años, ya que sus resultados son relevantes para la implementación de obras de protección ribereñas, en lugares estratégicos identificados por su mayor vulnerabilidad. Finalmente, dichas obras lograron mitigar el impacto generado al disminuir en un porcentaje el área inundada en la zona de estudio, desde la represa “Los Ejidos” hasta el puente Bolognesi en la provincia de Piura.
Disasters caused by floods are increasingly common around the world, such as the case in the western part of North and South America, due to the presence of the “El Niño” phenomenon, which causes an increase in rainfall and flow rates. The rivers causing floods. For this reason, this present work has carried a numerical simulation of flooding in the face of extreme events such as El Niño, with the purpose of reducing the area and level of flooding before probable and different events in areas close to riverbeds. Hydrological data of average flows and instantaneous maximums over a period of 40 years has been used. For the morphological characterization of the area, information has been used on a digital terrain elevation model (DEM), obtained from the SPOT-7 satellite, with a resolution of 6x6m. The hydrological in-formation was processed using the Gumbel method to obtain simulation flows for return periods of 2, 5, 10, 50, 100 and 500 years. The numerical modeling was carried out using HEC-RAS 5.0.7, the flood area for FEN 2017 was obtained and compared with the SENTINEL-2 satellite image for validation. Likewise, extreme events were modeled with return periods greater than 10 years, since their results are relevant for the implementation of riverine protection structures, in strategic locations identified with greater vulnerability. Finally, these works managed to mitigate impact showing reduction in a percentage of the flooding area in the study area, from “Los Ejidos” dam to Bolognesi Bridge, in the province of Piura.
Tesis

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Bazin, Pierre-Henri. "Écoulements lors d'inondations en milieu urbain : influence de la topographie détaillée et des échanges avec le réseau d'assainissement." Thesis, Lyon 1, 2013. http://www.theses.fr/2013LYO10241/document.

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Le but de cette thèse est d'étudier la modélisation détaillée des écoulements qui ont lieu lors des inondations urbaines. Dans une première partie, des écoulements en bifurcation incluant des petits obstacles génériques ou des profils de canaux avec trottoirs sont étudiés sur une maquette expérimentale, puis simulés numériquement avec le modèle bidimensionnel Rubar20. Les résultats expérimentaux et numériques montrent l'avantage d'inclure des obstacles de petite taille dans un modèle d'inondation urbaine, alors qu'il n'y a qu'un intérêt limité à utiliser une topographie détaillée des rues. Dans une deuxième partie, les interactions entre écoulements de surface et écoulements en conduites souterraines sont étudiées. Un modèle physique de système de drainage urbain permet de valider un modèle analytique prédisant les débits d'échange entre les deux couches d'écoulement. Une modélisation 1D/2D (conduite/rue) est mise en place avec les modèles Rubar3/Rubar20 et validée sur des écoulements expérimentaux observés sur le modèle physique. Dans une troisième partie, les inondations dans la ville d'Oullins (près de Lyon, France) sont étudiées. La modélisation des écoulements de surface est validée avec des données de terrain, et nous discutons l'intérêt de plusieurs représentations du milieu urbain. L'intégration du réseau d'assainissement dans un modèle 1D/2D reste affectée par plusieurs incertitudes, mais cette étape montre l'intérêt de la modélisation couplée pour décrire les interactions complexes des écoulements lors d'inondations urbaines, ainsi que les limites de l'approche développée pour les écoulements à faible profondeur
Aim of this thesis is to study the detailed modelling of flows that occur during urban floods. In a first part, bifurcation flows including small obstacles or channel profiles with sidewalks are studied on an experimental facility, and then numerically simulated with the two dimensional model Rubar20. Experimental and numerical results show the benefits of including small obstacles in an urban flood model, whereas there is only little benefit of using a detailed representation of the streets topography. In a second part, interactions between surface and underground pipe flows are studied. A physical model of an urban drainage system allows the validation of an analytical model predicting exchange discharges between both flow layers. A 1D/2D modelling (pipe/street) is set up with the models Rubar3/Rubar20 and validated on experimental flows observed on the physical model. In a third part, floods in the city of Oullins (near Lyon, France) are studied. Surface flows modelling is validated with field data, and we discuss the interest of several representations of the urban area. Integration of the sewer system in a 1D/2D model remains impacted by several uncertainties, yet this step shows the interest of the coupled modelling to describe complex flows interactions during urban floods, as well as limitations of the developed approach for shallow flows

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Heinzlef, Charlotte. "Modélisation d'indicateurs de résilience urbaine face au risque d'inondation : co-construction d'un système spatial à la décision pour contribuer à l'opérationnalisation du concept de résilience Assessing and mapping urban resilience to floods with respect to cascading effects through critical infrastructure networks » Operationalizing urban resilience to floods in embanked territories – Application in Avignon, Provence Alpes Côte d’azur region A spatial decision support system for enhancing resilience to floods. Bridging resilience modelling and geovisualization techniques Operating urban resilience strategies to face climate change and associated risks: some advances from theory to application in Canada and France." Thesis, Avignon, 2019. http://www.theses.fr/2019AVIG1197.

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Dans un contexte de dérèglement climatique, d’augmentation des inondations en milieu urbain,d’augmentation des incertitudes, les gestionnaires urbains sont obligés d’innover pour concevoir des stratégies de gestion des risques adéquates. Parmi ces stratégies, rendre les villes résilientes est devenu un impératif. Le concept de résilience est un concept pluridisciplinaire qui définit la capacité d’un système à absorber une perturbation et à récupérer ses fonctions par la suite. Cette notion renvoie à une innovation technique, urbaine, sociale, architecturale, économique et politique et enjoint à une remise en question des stratégies traditionnelles de gestion du risque. Cette injonction à l’innovation s’adapte parfaitement à la complexité urbaine, économique, politique, sociale, écologique du monde contemporain. De ce fait, le concept de résilience s’intègre aux enjeux d’étalement urbain et aux risques associés. Pourtant, malgré cette adéquation théorique et conceptuelle, la résilience demeure complexe à intégrer dans les pratiques des urbanistes et acteurs territoriaux. Sa multitude de définitions et d’approches a favorisé son abstraction et son manque d’opérationnalisation. Face à ce constat, cette recherche se propose de répondre à ces lacunes opérationnelles en construisant un système spatial d’aide à la décision afin de clarifier et favoriser l’intégration du concept dans les pratiques urbaines. L’idée défendue est que la résilience urbaine incarne les aptitudes et capacités d’une ville et de sa population à mettre en place avant, pendant et après un événement perturbateur de façon à en limiter les impacts négatifs. Ce positionnement scientifique permet donc d’analyser la résilience urbaine sur un long pas de temps, mettant en avant des capacités proactives que le système urbain doit développer de façon à (ré) agir face à l’inondation. Ce travail s’est appuyé sur un partenariat socio-économique avec la Ville d’Avignon et son Service SIG (Système d’Information Géographique). L’approche a permis de construire trois indicateurs de mesure afin d’aborder la résilience urbaine, technique et social. Ces indicateurs ont permis d’acquérir des informations sur les variables définissant des potentiels de résilience qui favoriseraient l’émergence d’une réponse adéquate face à une inondation urbaine. L’utilisation de techniques de géovisualisation a permis de favoriser la visualisation des traitements et des résultats afin d’expliciter la démarche auprès des gestionnaires urbains. Parallèlement, des ateliers de concertation ont été montés afin de présenter et discuter des résultats obtenus grâce aux indicateurs avec les responsables et gestionnaires des infrastructures critiques.La co-construction de ces indicateurs, afin de construire une analyse et une connaissance autour de la résilience urbaine, suivis de la mise en place d’ateliers avec les acteurs du territoire, afin de favoriser le processus décisionnel territorial, a permis de développer une culture de résilience. Ce système spatial d’aide à la décision a donc permis la mutualisation des connaissances théoriques et pratiques autour des questions de risques urbains et de résilience afin de parvenir à un consensus nécessaire pour la prise de décision et l’opérationnalisation de la résilience
In a context of climate change, increased urban flooding and increased uncertainty, urbanmanagers are forced to innovate to design appropriate risk management strategies. Among thesestrategies, making cities resilient has become an imperative. The concept of resilience is amultidisciplinary concept that defines the ability of a system to absorb a disturbance and then recoverits functions. This concept refers to technical, urban, social, architectural, architectural, economic andpolitical innovation and calls into question traditional risk management systems. This injunction toinnovation is perfectly adapted to the urban, economic, political, social and ecological complexity ofthe contemporary world. As a result, the concept of resilience is integrated with urban sprawl issues andassociated risks. However, despite this theoretical and conceptual adequacy, resilience remains complexto integrate into the practices of urban planners and territorial actors. Its multitude of definitions andapproaches have contributed to its abstraction and lack of operationalization.In response to this observation, this research aims to address these operational gaps by buildinga spatial decision support system to clarify and promote the integration of the concept into urbanpractices. The idea behind this approach is that urban resilience embodies the abilities and capacities ofa city and its population to develop before, during and after a disruptive event in order to limit itsnegative impacts. This scientific positioning therefore makes it possible to analyze urban resilience as acontinuum, highlighting proactive capacities that the urban system must develop in order to (re)act inthe face of flooding. This work was based on a socio-economic partnership with the City of Avignonand its GIS Service (Geographic Information System). The approach made it possible to build threemeasurement indicators to address the urban, technical and social resilience of the Avignon area. Theseindicators have made it possible to acquire information on the variables defining potential resilience thatwould foster the emergence of an adequate response to a natural disaster and more precisely to an urbanflood. The use of geovisualization techniques has made it possible to visualize treatments and results inorder to explain the approach to urban managers. At the same time, consultation workshops were heldto present and discuss the results obtained through the indicators with critical infrastructure managersand managers.The co-construction of these indicators, in order to build an analysis and knowledge aroundurban resilience, followed by the implementation of workshops with stakeholders in the territory, inorder to promote the territorial decision-making process, has made it possible to develop a culture ofresilience. This spatial decision support system has therefore made it possible to pool theoretical andpractical knowledge on urban risk and resilience issues in order to reach the consensus necessary fordecision-making and the operationalization of resilience

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Maillot, Mathias. "Étude des remontées de nappe de Paris et de la Petite Couronne lors des épisodes de crue de la Seine et de la Marne." Electronic Thesis or Diss., Paris Sciences et Lettres (ComUE), 2019. http://www.theses.fr/2019PSLEM057.

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La gestion du risque inondation lors des crues de la Seine et de la Marne constitue un enjeu majeur en agglomérationparisienne du fait de l’importante densité de population et de la vulnérabilité des infrastructures stratégiques qui s’ytrouvent. Le phénomène de remontée de nappe accompagne les épisodes de crue via le transfert des eaux de surfacesvers les eaux souterraines. Le contexte hydrogéologique est fortement affecté par la régulation des niveaux d’eau denappe et de rivière, par le caractère hétérogène du milieu géologique, et par la présence de structures souterraines(caves, parking, métro).Cette étude décrit le fonctionnement de l’aquifère de surface de Paris et de la petite couronne selon deux grands axesde recherche : (1) les observations piézométriques sont analysées à l’aide d’outils géostatistiques afin de produire unesérie de cartes piézométriques intégrant le statut de connexion nappe-rivière. La surface piézométrique est ainsi spatialiséeen fonction du régime hydrologique (crue/hors crue). (2) La modélisation hydrogéologique de Paris et de la petitecouronne. Le modèle hydrogéologique, construit à partir de plusieurs bases de données géologiques (IGC, SGP, BRGM),est exploité pour caractériser le risque inondation par remontées de nappes
The Paris urban area is a densely populated city where strategic infrastructures and population are subject to the floodingrisk during Seine and Marne Rivers flood events. The groundwater rising process is associated with flood event throughthe draining of streamwater toward the aquifer. The hydrogeological environment into an urban context is strongly affectedby the anthropic activities like permanent pumping and underground structures occurrence (basements, subway, etc. . . ).This study is based on two different approaches to describe the superficial aquifer of Paris urban area: (1) the water tablemapping using geostatistical tools helps to determine the streamwater-groundwater connection status, and to describethe hydrogeological functioning of the studied area. (2) The modelling of groundwater during flood events allows for theunderstanding of the risk from groundwater flooding

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(11267826), Neel Arun Salvi. "DELINEATING THE IMPACT OF STORMWATER INFRASTRUCTURE USING INTEGRATED FLOOD MODELING." Thesis, 2021.

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The planet is currently experiencing a massive shift in the migration of people towards highly populous metropolitan regions which offer a better quality of life, which has resulted in rapid development and expansion. Meanwhile, the recent studies on climate change have shed light on precipitation events becoming increasingly wetter and intense. This rapid change in the land use patterns coupled with the climate change has increased the risk of flooding and puts the massive investment in the infrastructure, economy, and human life at a greater risk than ever before. This study aims to analyze the impacts of the stormwater infrastructure on the hydrology and hydraulics of highly urbanized environments. Traditional flood modeling approaches of independent hydrologic and hydraulic models have progressed into more complex models which can integrate the surface and sub-surface along with their interactions as the understanding of these physical processes and the availability of computational power has increased. A fully integrated hydro-systems model based on a distributed modeling approach is developed for a portion of the City of Minneapolis in Minnesota, USA which incorporates the surface hydraulics, stormwater infrastructure, vadose zone and a dynamic water table which realistically represents all the hydrologic and hydraulics processes. The result of this study shows the incorporation of the stormwater infrastructure in the integrated model leads to lower flood inundation areas, reduced vadose zone storage and lowered groundwater table for design flows as well as real events. The model displayed consistent results for the impact of stormwater infrastructure when tested across varied antecedent soil conditions. Ultimately this study proposes the implementation of a fully integrated hydro-systems modeling approach which link the hydrology and the hydraulics of the surface, sub-surface and stormwater infrastructure systems for a better representation of the flood hydrodynamics in urbanized regions.

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"Propagation of Radar Rainfall Uncertainties into Urban Flood Predictions: An Application in Phoenix, AZ." Master's thesis, 2020. http://hdl.handle.net/2286/R.I.57215.

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abstract: The Phoenix Metropolitan region is subject to intense summer monsoon thunderstorms that cause highly localized flooding. Due to the challenges in predicting these meteorological phenomena and modeling rainfall-runoff transformations in urban areas, the ability of the current operational forecasting system to predict the exact occurrence in space and time of floods in the urban region is still very limited. This thesis contributes to addressing this limitation in two ways. First, the existing 4-km, 1-h Stage IV and the new 1-km, 2-min Multi-Radar Multi-Sensor (MRMS) radar products are compared using a network of 365 gages as reference. It is found that MRMS products consistently overestimate rainfall during both monsoonal and tropical storms compared to Stage IV and local rain gauge measurements, although once bias-corrected offer a reasonable estimate for true rainfall at a higher spatial and temporal resolution than rain gauges can offer. Second, a model that quantifies the uncertainty of the radar products is applied and used to assess the propagation of rainfall errors through a hydrologic-hydraulic model of a small urban catchment in Downtown Phoenix using a Monte Carlo simulation. The results of these simulations suggest that for this catchment, the magnitude of variability in the distribution of runoff values is proportional to that of the input rainfall values.
Dissertation/Thesis
Masters Thesis Civil, Environmental and Sustainable Engineering 2020

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Gordon, Ross M. "Next generation hydraulic modeling for inundation mapping and flood warning in complex urban systems." Thesis, 2007. http://hdl.handle.net/1911/20556.

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This thesis presents a novel methodology for predicting flooding in complex urban environments. MIKE-FLOOD was used to dynamically model the interactions between overland flow, storm sewer drainage, and tail water by linking a modeled storm sewer system and outfall with a detailed 2D hydrodynamic overland flow model to generate animations displaying the location, depth, and duration of flooding. This research project focused on the Texas Medical Center (TMC), located in the Harris Gully watershed, which endured over 3 billion dollars in flood damage from Tropical Storm Allison in 2001. The system of integrated models was calibrated versus TS Allison and matched commendably with an absolute average error of less than 3 inches. This new approach to predicting flooding in complex urban systems has shown to be easier to set up and more dynamic and powerful than other more conventional approaches to urban inundation mapping and flood prediction.

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Yang, Bo. "Ecohydrological Planning for The Woodlands: Lessons Learned After 35 Years." 2009. http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-7179.

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The Woodlands, Texas, is a 27,000-acre new town created with Ian McHarg's ecohydrological planning approach. The Woodlands is the best example of ecologically based new town planning in the United States during the 1970s. The Woodlands survived storms in excess of one-hundred-year levels in 1979 and 1994 with little property damage, while Houston, 31 miles away, was severely flooded in both events. For the past three decades, very few studies have been conducted to assess the effectiveness of McHarg's planning approach. The objective of this study is three fold: (1) To document McHarg's ecohydrological planning concepts, implementation and unveil the barriers to continue his approach; (2) To compare flood mitigation effectiveness of different drainage systems used in The Woodlands development; and (3) To simulate "what if" land-use scenarios using different planning approaches. Original development information is collected from published monographs, journal articles, newspapers and designers' collections. Geographic Information System (GIS) parcel data are obtained from Montgomery County Appraisal District. Streamflow data are acquired from the USGS website. Weather data are downloaded from the NOAA website. Land use and land cover data are collected from various national datasets. Two GIS hydrologic models--the Soil and Water Assessment Tool (SWAT) and the Kinematic Runoff and Erosion model (KINEROS)--are used for watershed simulation. The statistic analysis tool SPSS is used for correlation analysis. Results show that McHarg's planning approach was followed in the early phases of development (1974-1996) but was largely abandoned in the later phases when its ownership was changed in 1997. McHarg's approach ceased to be implemented because of the low public acceptance of ecohydrological planning strategies and the conflicts between short-term investment return and long-term environmental stewardship. In addition, comparative study shows that the early phases of development responded to rainfall similarly to its pre-development forest conditions. However, the later phases generated runoff volumes three times greater than the early phases. Therefore, McHarg's ecohydrological planning approach demonstrates flood mitigation effectiveness that is superior to the conventional approach. Finally, using soil permeability to coordinate development density and land use presents a viable solution for mitigating environmental impacts from a stormwater perspective.

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Jensen, Christopher Allen. "A hydrologic assessment of using low impact development to mitigate the impacts of climate change in Victoria, BC, Canada." Thesis, 2012. http://hdl.handle.net/1828/4211.

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The purpose of this study is to determine if Low Impact Development (LID) can effectively mitigate flooding under projected climate scenarios. LID relies on runoff management measures that seek to control rainwater volume at the source by reducing imperviousness and retaining, infiltrating and reusing rainwater. An event-driven hydrologic/hydraulic model was developed to simulate how climate change, land use and LID scenarios may affect runoff response in the Bowker Creek watershed, a 10km2 urbanized catchment located in the area of greater Victoria, British Columbia, Canada. The first part of the study examined flood impacts for the 2050s (2040-2069) following the A2 emissions scenario. For the 24-hour, 25-year local design storm, results show that projected changes in rainfall intensity may increase flood extents by 21% to 50%. When combined with continued urbanization flood extents may increase by 50% to 72%. The second part of the study identified potential locations for three LID treatments (green roofs, rain gardens and top soil amendments) and simulated their effect on peak in-stream flow rates and flood volumes. Results indicate that full implementation of modeled LID treatments can alleviate the additional flooding that is associated with the median climate change projection for the 5-year, 10-year and 25-year rainfall events. For the projected 100-year event, the volume of overland flood flows is expected to increase by 1%. This compares favourably to the estimated 29% increase without LID. In term of individual performance, rain gardens had the greatest hydrologic effect during more frequent rainfall events; green roofs had minimal effect on runoff for all modelled events; and top soil amendments had the greatest effect during the heaviest rainfall events. The cumulative performance of LID practices depends on several variables including design specifications, level of implementation, location and site conditions. Antecedent soil moisture has a considerable influence on LID performance. The dynamic nature of soil moisture means that at times LID could meet the mitigation target and at other times it may only partially satisfy it. Future research should run continuous simulations using an appropriately long rainfall record to establish the probabilities of meeting performance requirements. In general, simulations suggest that if future heavy rainfall events follow the median climate change projection, then LID can be used to maintain or reduce flood hazard for rainfall events up to the 25-year return period. This study demonstrates that in a smaller urban watershed, LID can play an important role in reducing the flood impacts associated with climate change.
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Dissertations / Theses on the topic 'Urban flood modeling'

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