Dissertations / Theses on the topic 'Flooding impacts'

This thesis develops a method to analyze the roll response of a vessel during a damaged (flooded) scenario. This was done by developing a time-domain method in which the damaged compartment was flooding while the ship is simultaneously subjected to a seaway. The KRISO containership was used as a test hull and was subjected to three flooding conditions. These flooding conditions involved flooding Hold 5, Hold 3, and Hold 1 separately. Newmark’s Beta method for linear acceleration was used to solve the roll motion of equation in which the hydrodynamic coefficients A44, B44, and C44 were predetermined from linear strip theory for various drafts and trim angles. The roll response in the transient flooding state and the steady state, after flooding ceased (fully damaged state), while in wave action was simulated and plotted. The amplitudes from the initial and damaged steady states were recorded at the given wave frequency and wave amplitude, to generate the roll response amplitude operators for the vessel from wave frequency ω = 0.1 rad/s to ω = 2.1 rad/s. Analysis of the RAO curves revealed that the KRISO was not made significantly more unstable by the flooding, for the conditions that were considered, for nearly all wave frequencies except the natural frequency of 0.5 rad/s.

CHDS State/Local
Flooding matters. As the nation's most common natural hazard, flooding costs this nation economically, disrupts communities and commerce, and renders communities and extrapolated-the nation-less than fully postured for other homeland security threats. It will not get better. Demographics leading to more people living in flood-hazard areas and forecasted increases in precipitation are converging to create the perfect storm. This thesis examines two national policies that can influence the impact and costs of flooding: The National Flood Insurance Program and the Robert T. Stafford Disaster Act. Examination and research reveals that the NFIP has failed to achieve its goals of reducing flood losses and political, economic, and societal factors serve to make reforming the NFIP effectively less than likely. A policy options analysis examines how changes to the Stafford Act might influence a reduction in the impact and costs of flooding where the political, economic, and societal factors at play may lend to favorable implementation consideration. The policy options include changing enforcement and incentive provisions of the Stafford Act along with a proposal to begin a national dialogue on mitigation through the creation of a National Mitigation Collaborative Consortium

This research is the first of its kind in Bangladesh. It focuses upon flood losses in urban sectors of the country’s economy. The broad research question is whether flood impacts in urban or non-agricultural sectors are important in Bangladesh, given that it is currently an agricultural economy. The research examines the applicability of existing urban flood impact assessment methods, and develops methods suitable to Bangladesh. An important aim is to accumulate a knowledge base of flood impacts in the urban or non-agricultural sectors. With appropriate modifications, flood loss assessment methods generated in developed countries may be applied in a developing country such as Bangladesh. However, the ‘synthetic’ approach of constructing standard potential flood loss data sets is not feasible. Using surveys of actual floods, the construction of reasonably high-quality ‘average’ data sets proves to be feasible, as floods in Bangladesh are not sparse. The construction of data sets through regressions is preferred because it is more realistic and cost-effective. The widely used unit-loss model is found to be applicable to appraisals of urban protection schemes. However, the successful application of the model depends on the accuracy of land use and land level survey data, and detailed hydraulic and hydrological information. In Bangladesh, this form of modelling is found to be suitable for project appraisals ranging from small to intermediate scale. Some methods, however, are suitable for up to full scale appraisals. The major achievement of the research is that flood loss potential for urban Sectors has been thoroughly investigated, providing flood loss data of a significantly higher quality that are available hitherto in Bangladesh. In providing these data the research is a significant advance upon the methods recommended within the existing FPCO Guidelines for project assessment, and those used in recent FAP urban protection studies. The assessments methods developed and the standard damage data sets constructed may now be used to appraise urban protections, which will also facilitate evaluation of agricultural projects more comprehensively through incorporating non-agricultural losses that can be averted in such schemes. The research reveals that the urban sectors of the economy are highly vulnerable to floods. Induced by rapid urbanisation, potential urban flood losses in Bangladesh are expected to be progressively more important in the future. Poverty is found to be fundamental to flood hazard vulnerability: the poorest of the poor have the most to lose in proportional (to value) terms. A high priority can now be given to protect urban and commercial centres in Bangladesh. Given limited resources in Bangladesh, low-cost non-structural measures are also important. Local knowledge and informal flood warning systems have a positive bearing on resilience building. Community cohesion, together with family kinships, are also important in this respect. Different types of floods (e.g. river flood, flash flood and tidal surge) are associated with differential impacts: tidal floods prove the most destructive. Flood impacts at the macro-level are not found to be as severe as those at the micro-level. The findings suggest that floods deepen poverty and help widen the income gap between rich and poor. This problem poses further research questions regarding ‘equity’ and sustainable development. Project appraisal methods using conventional ‘economic efficiency analysis’ need to be re-calibrated in order to confront the problems relating to inequity and sustainable development, especially in the context of existing socio-economic conditions in Bangladesh.

This paper examines the possible contribution of evolutionary economics to macro-economic modelling of flood impacts to provide guidance for future economic risk modelling. Most macro-economic models start from a neoclassical economic perspective and focus on equilibrium outcomes, either in a static or dynamic way, and describe economic processes at a high level of aggregation. As a consequence, they typically fail to account for the complexity of social interactions and other behavioural responses of consumers and producers to disasters, which may affect the macroeconomic impacts of floods. Employing evolutionary principles and methods, such as agent-based modelling, may help to address some of the shortcomings of current macro-economic models. We explore and discuss the implications of applying consumer and producer heterogeneity, bounded rationality, network effects, social and technological learning, co-evolution and adaptive policy-making concepts into existing economic frameworks for the assessment of macro-economic impacts of floods. (authors' abstract)

Environmental change will have significant impacts on microbial ecosystems. Microorganisms dominate most biogeochemical pathways, and environmental perturbations may alter these functions. Such functions include nutrient cycling, pollution abatement and greenhouse gas emission, and it is paramount that the impact of environmental change on ecosystems is understood. High throughput DNA sequencing provides a window into complex microbial communities and their functional potential, thus allowing us to empirically study how such communities respond to predicted future environments. There are, however, caveats and challenges associated with such technologies, particularly with converting billions of sequencing base calls into species and function counts. This thesis firstly quantifies the performances of sequence annotation tools and parameters using a simulated metagenome. It is found that tools differ in performance, and that parameter selection can significantly reduce annotation accuracy e.g. One Codex correctly annotated many sequences at the genus level, whereas MG-RAST RefSeq produced many false positive annotations. The results provide a guideline to quantitatively inform researchers about the impacts of certain choices on annotation performance, and show that some published studies may be drawing incorrect conclusions. This thesis also investigates the impacts of increased flooding frequency and duration on soil microbial ecosystems, in line with predicted climate change. Increased frequency has significant impacts on biodiversity, community composition and potential function. SkyLine, a novel, continuous gas flux measuring system, was used to record CO2 and CH4 fluxes. Increased flooding duration significantly reduced CH4 oxidation and increased CO2 assimilation, with the combined global warming potential of these gasses reduced.

From 2010 The Flood and Water Management Act has given the Environment Agency and local authorities in the United Kingdom a statutory requirement to manage flooding from groundwater. A robust, long-term groundwater flood risk assessment methodology was developed using the Pang/Lambourn catchment in West Berkshire as a case study. A recharge model based on a soil moisture budget was built in GIS and tested against observations. The timing and mechanism of flow in the vadose zone was also assessed using cross-correlation analysis between rainfall and borehole responses for a better understanding of recharge processes. Regional MODFLOW models were developed for saturated groundwater flow using input from the recharge model. This integrated model was then coupled with a Global Climate Model using a stochastic weather generator to downscale output to the catchment. An ensemble of high and low climate change scenarios suggests there will be between a 5.5% and 27% reduction in recharge over the coming century and mean groundwater levels will lower by up to 3.8%. Land use modification characterised by afforestation and urbanisation resulted in nuanced changes in the spatial distribution of recharge as well as a further mean reduction of 6.8% on top of the climate change impacts. Groundwater flood hazard maps were developed and integrated with a social vulnerability index to identify 1.7 km2 of the Pang/Lambourn at high risk. In the Pang catchment this represents around 1400 properties. Climate and land use change scenarios suggest however that the risk of groundwater flooding in the catchment will decrease considerably (25-98%) over the next century. This reduction in risk is likely to make mitigation through targeted land use modification unnecessary.

Historically wildfires have been beneficial to forests, however, human developments have encroached on forests when wildfire was artificially suppressed by federal and state agencies. The area burned by wildfire each year has increased twenty-fold in the past three decades. Large, high severity fires pose increased threats to human and aquatic communities within and downstream of the burned area due to post-wildfire effects on flooding and sedimentation. We need to understand the impacts of wildfires to be able to mitigate their damages and to recognize their potential benefits. This research addresses the questions: 1) Do wildfires impact rural and urban economies differently and what are managers doing to adapt management strategies? 2) Do floods increase after wildfire, and if so, by how much? 3) Do wildfires affect fish habitat, and if so, how? Chapter 2 provides insight into both positive and negative economic impacts on rural and urban economies after a wildfire, and brings to light manager’s inability to change their management strategies due to constraints such as budget limitations. Chapter 3 measures how floods change in nine basins after a wildfire occurred, and reveals that floods may increase up to 880 percent after a fire. Chapter 4 demonstrates that fish habitat is significantly altered after wildfires and why change is harmful to the fish. This work shows that wildfire significantly changes the burned and surrounding area, and that more work is needed for a better understanding of how to predict how a specific area will respond to wildfire.

A warmer climate is expected to increase the risks of natural disasters globally. China is one of the hotspots of climate impacts since its infrastructures and industries are often hard hit. Yet little is known about the nature and the extent to which they are affected. This thesis builds novel system-of-systems risk assessment methodologies and data for China, representing infrastructures (energy, transport, waste, water and digital communications) as interdependent networks that support spatially distributed users of infrastructure services. A unique national-scale geo-spatial network database containing 64,834 existing infrastructure assets is assembled. For the first time, flood and drought exposure maps of China's key infrastructures are created, highlighting the locations of key urban areas to understand how its infrastructures and population could be exposed to climate impacts. To deepen the understanding of how climate change will affect the Chinese infrastructure system and hence its economy, economic impact modelling is applied. The research combines a detailed firm-level econometric analysis of 162,830 companies with a macroeconomic input-output model to estimate flood impacts on China's manufacturing sector over the period 2003 - 2010. It is estimated that flooding on average reduces firm output by 3.18% - 3.87% per year and their propagating effects on the Chinese macroeconomic system to be a 1.38% - 1.68% annual loss in total direct and indirect output, which amounts to 17,323 - 21,082 RMB billion. Several infrastructure sectors - electricity, the heat production and supply industry, gas production and supply, the water production and supply industry - are indirectly affected owing to the effects of supply chain disruptions. Taking the above analysis one step further, this thesis explores how climate disaster risks may change over the period 2016 - 2055, using flooding as a case study. A global river routing (CaMa-Flood) model at a spatial resolution of 0.25° x 0.25° is applied and downscaled for China, using the daily runoff of 11 Atmospheric and Oceanic General Circulation Models (AOGCMs). Combining the flood analysis with the infrastructure database, this research demonstrates the changing locations of exposed infrastructures and their dependent customers. We find that by 2055, the number of infrastructure assets exposed to increasing probability of flooding under RCP 4.5 are 41, 268, 115, 53, 739, 1098, 432 for airports, dams, data centres, ports, power plants, rail stations, reservoirs respectively - almost 8% of all assets for each sector. The lengths of line assets exposed to increasing flood hazards are 14,376 km, 32,740 km, 102,877 km and 25,310 km oil pipelines, rail tracks, roads and transmission lines respectively. Under RCP 8.4, the numbers increase to 51, 301, 137, 71, 812, 1066, 424 for point assets. Linear assets increase to 19,938 km, 39,859 km, 122,155 km and 30,861 km. Further, we demonstrate that indirect exposure of customers reliant on those infrastructure assets outside the floodplain could also be high. The average number of customers affected by increasing flood probabilities are 54 million, 114 million and 131 million for airports, power plants and stations respectively. However, within this aggregate increase there is large spatial variation, which has implications for spatial planning of adaptation to flood risk to infrastructure. This is a first substantial study of flood impacts to infrastructure both in terms of direct exposure and their indirect implications. Lastly, to shed some light on the potential vulnerability of China's infrastructure system to climate impacts, this thesis develops a framework that identifies the drivers of infrastructure development in China using evidence from policy documents and a unique geospatial dataset for the years 1900 - 2010. Understanding these drivers will provide a useful foundation for future research in terms of developing infrastructure models that could project the locations of future infrastructure assets and networks in China, thereby quantifying how China's infrastructure exposure and vulnerability will change over time. Overall this research provides an integrated system-of-systems perspective of understanding network and economic vulnerabilities and risks to Chinese energy, transport, water, waste and digital communication infrastructures due to climate change. This is crucial in informing the long-term planning and adaptation in China.

Transitional land uses produced through urbanisation continue to change the landscape and fragment ecological structures including green spaces across Europe (Nilsson et al., 2013). Green spaces offer significant benefits to humans, contributing to wellbeing and life satisfaction (Taylor, 2002). The understanding of how these unique green spaces spaces function and provide benefits to humans, and how landscape change in peri-urban contexts affects their performance, is important. The scope of this research is to contribute to an understanding of landscape fragmentation within some of Europe's polycentric urban regions, their peri-urban green spaces, and the associated impacts upon human quality of life. Two urban regional case studies, Paisley near Glasgow, Scotland, and Vantaa, near Helsinki, Finland were analysed and compared. The results indicate that humans interacting with more physically or ecologically fragmented peri-urban green spaces have higher self-reported life satisfaction levels. Though no statistically significant characteristics were apparent between life satisfaction and fragmented green space characteristics, this research was able to identify those specific structural attributes and physical characteristics of interstitial peri-urban green spaces within a polycentric region in a fragmented state that contribute to the physical, social, and psychological aspects of human wellbeing. The statistically significant eco-spatial characteristics of polycentric peri-urban interstitial green spaces that are reported to impact human wellbeing are the size, proximity, maintenance and management, and the level of greenness within its vegetation composition and setting. Overall, a spatially diverse, fragmented, peri-urban landscape whose green spaces are extensively sized, naturalistically shaped with horizontal vegetation and normal sized edges, most often parks or woodlands or forests which are integrated and physically connected to another green space which is moderately clean and somewhat safe as well as being located close to or adjacent to a heavy-trafficked road provide the most human wellbeing benefits.

Flooding is a global challenge that has plagued mankind throughout history, affecting over 164 million people worldwide in 2007 alone. As the frequency of flooding increases in England and Wales coupled with an increase in the number of properties at risk of flooding and the attendant huge (insured) economic costs of flooding, the services received by homeowners during flood damage repair works, have not been spared criticism, Both the Welsh Consumer Council report and the Warwickshire Trading Standards report raised serious questions about the level of service in insurance claims for the repair of flood-damaged domestic property. This research project was therefore aimed at investigating the level of service quality and determinants of homeowners’ satisfaction in England and Wales with respect to flood damage repair works during insurance claims. A comprehensive literature review was conducted on customers’ needs, satisfaction and service quality, flooding and related issues, and the repair of flood damaged domestic property, in order to set the framework for the research and shape the development of the research questions/hypotheses. The study employed a two-phased sequential mixed methods approach, commencing with 20 in-depth interviews with homeowners, repairers, insurers and loss adjusters. Findings from the initial exploratory study (and from the literature review) informed the development of a questionnaire instrument, which incorporated elements of SERVQUAL, the generic service quality measurement instrument. Survey data were collected for the quantitative phase of the study from a sample of 126 homeowners, which was then analysed to test the hypotheses put forward in the study. The data did not yield a set of reliable and interpretable factors of service quality from the three service quality scales used to measure homeowners’ perceptions of the performance of insurers, loss adjusters and contractors. However, of the three key service providers, the contractor’s performance was the best predictor of homeowners’ overall satisfaction during flood damage reinstatement claims, accounting for seven times the combined unique contribution of insurance and loss adjusting firms. In addition, satisfaction levels were significantly different for homeowners whose claims for repair works were completed within six months compared to those repairs exceeded twelve months. The thesis concludes with implications of the findings for practice as well as recommendations for further research. It is argued that knowledge of the determinants of homeowners’ satisfaction with services during the repair of flood damaged property, is beneficial not only to insurers, loss adjusters and repairers but to homeowners as well.

Developing countries have been rapidly urbanising over the last decades, resulting in major environmental pressures and increased vulnerability to natural disasters. A complex combination of factors, including climate change, land use change, poorly implemented regulation and a lack of integrated planning has often resulted in environmental degradation and disproportionate impacts of natural disasters affecting millions worldwide, particularly in tropical cities. The main aim of this study is to understand the effects of land-use and climate change on flooding in the Greater Port-Harcourt watershed. The specific research objectives were: to understand the historical and future land use /land cover changes; to understand the magnitude of change in hydrologic and hydraulic conditions due to land-use and climate changes; to assess the influence of different forest mitigation scenarios on peak-discharge; and to make recommendations on how to improve future planning using insights from this study. Methodologically, the post-classification change detection method was applied to examine the extent and nature of historical LULC changes using remotely sensed data. Future LULC changes were estimated by superimposing the 2060 digitised Masterplan map on the year 2003 baseline imagery. Hydrologic changes were assessed using HEC-HMS model, while changes in the hydraulic condition were assessed using HEC-RAS model. Model output was further used to map flood hazards, flood zones and damage potential. Priority areas and infrastructure at risk were identified by means of their location in flood zones and exposure to floods with high damage potential. On the extent of change, this study revealed that urbanisation and loss of agricultural land had been the dominant and intensive land use change in the watershed. Urbanisation is projected to almost double its 2003 extent by 2060 and is likely to remain the dominant force of land use change. On the nature of change, this study found that urban land was the most dynamic in terms of gross gain and net change. It exhibited the grossest gain (about 9% of the watershed) and the grossest loss leading to a high net change of about 8.6%. In fact, the most prominent transition was the conversion of agricultural land (about 422km2) to urban land, and roughly 93.3% of all conversions to urban land resulted from agricultural land. On the process of change, urban land mainly experienced a net-type of change (change in quantity), whereas changes in agricultural land was more of a swap-type of change (change in location). Importantly, the study reveals that the impact on flood flow was historically significant (about 68%) and is projected to amplify in future, however, these changes are largely attributed to increased storm size. Urbanisation is likely to have little or no impact on annual maximum peak flow at the watershed scale; however, urbanisation is projected to have a considerable impact on peak flow in a number of subbasins, which could have severe implications for flash flooding in those subbasins. Similarly, afforestation could have little or no impact on future maximum peak flow when assessed at the watershed scale. Although some subbasins experienced changes in peak flow, the effect of forest is variable. The study concludes that although the impact of urbanisation is projected to be insignificant at the watershed scale, it could also increase flood risk due to increasing developments in floodplains and channel encroachment. Priority infrastructure and areas requiring urgent flood risk management include the Port-Harcourt seaports, Onne seaport, the University of Science and Technology and cement factory. Priority areas in the Masterplan are mainly in the south (Phase 3), comprising of the Air force base and the residential area near Onne seaport. Lastly, approximately 8.1km and 189m of road and rail network are at greater risk of flooding by means of their exposure to floods with the highest damage potential. Based on this study, I have furthered understanding by showing that the transition to urban land category was dominated by net changes (i.e. changes in quantity). I have also furthered understanding by showing that substantial changes in future urban land-use may not have significant effect on flood parameters. My main contribution to knowledge is that despite the high rate of urbanisation in the GPH watershed and its minimal impact on flooding (which could be due the large size of the storm and watershed), urbanisation could still increase flood risk due to greater exposure of elements at risk in the flood plains to damaging floods. Based on the results, the study recommends that the development authorities should integrate both structural measures (mainly for flood defence around existing developments) and non-structural measures (primarily for future developments). For flood risk management research, this study recommends that conclusions about the effects of urbanisation should not be made solely on the basis of changes in hydrology and river hydraulics, however researchers should also consider the exposure of important elements at risk within the floodplains under study to better understand the effects of urbanisation. Moreover, to better understand urbanisation effects on runoff dynamics in other watersheds, this study recommends that research efforts should be concerted in understanding subbasin-scale changes given that the effects of urbanisation are more pronounced in smaller basins.

Flooding of residential property is a real and growing phenomenon in the UK causing short and long-term detriment of various kinds to its victims. The issue of potential decrease in value of those properties which are located on the floodplain, though much discussed in the media, has received scant attention in the UK research literature. An extensive literature survey has revealed a need for methodological innovation in the field of temporal impact of flooding and the inadequacy of the current paradigms for inclusion of insurance into flood modelling. A wide-ranging review of data sources, including discussion with industry experts, has identified the requirement to generate primary data on the availability and cost of flood insurance. A novel framework has been developed for this research. This framework is an extension of the recent research in flood modelling and incorporates ideas from the wider house price analysis literature. Data collected via a questionnaire survey of householders has been combined with secondary data on property prices and flood designation in order to attribute any loss in property value to the correct vector of underlying flood status. The output from this study makes a contribution to the understanding of the impact of flooding on house prices, allowing for better valuation advice. Empirical findings are that the understandable concerns of residential property owners at risk of flooding regarding long term loss of property value are largely unfounded. Price discounts are observed for some recently flooded areas but they are temporary Improved appreciation of the impact of claims and flood risk on the cost of insurance has also emerged. The insurance market was not found to be instrumental in reducing the price of property. The output from the study also makes a methodological contribution in extending concepts relating to the relationship between flooding, insurance and house prices. This development is anticipated to facilitate refinement and updating of the empirical findings with reduced effort in the light of future events.

This thesis presents a methodological approach, the flood footprint framework, to capture the total economic costs of flooding events, as some of the most damaging climatic disasters. Economic costs are constituted by physical destruction, and all cascaded disruptions caused by the direct destruction. The method uses the fundamentals of Input-Output modelling, which is founded on the conceptualisation of the circular flow of the economy, representing the complex transactions between producers and intermediate and final consumers, for each sector, in an algebraic array. The solution of the equations’ system allows quantification of direct and indirect impacts along the value chain from changes in final demand. The flood footprint model further extends to capture changes in production due to the distortions of the economic equilibrium caused by flooding events, and to simulate the economy’s recovery. Sources of flooding disruption within the model arise from capital constraints, disruptions to labour force, and behavioural changes in final consumption. The method was applied to four case studies. The outcomes support the lesson that losses from a disaster are exacerbated and disseminated to other economies throughout economic mechanisms, and those knock-on effects (or indirect damages) constitute a substantial proportion of total economic losses, where non-directly flooded sectors might be also severely affected. The main implications for adaptation strategies are the review of the dynamics of direct and indirect damages and to unveil vulnerable hotspots along the value chain. This would allow an efficient allocation of investment resources and minimisation of socioeconomic damages during post-flood economic recovery. The key contribution of this thesis is a comprehensive methodology for assessing the total economic impacts of flooding events, considering elements that had not been taken into account together before, by incorporating multidisciplinary techniques for evaluation and projection of future scenarios, and bringing the analysis to a multiregional (global) scale.

This thesis aims to address the role of uncertainty in climate change impact studies, with particular focus on the impacts of climate change on UK flooding. Methods are developed to quantify the uncertainty associated with climate variability, hydrological model parameters and flood frequency estimation. Each is evaluated independently, before being combined to assess the relative importance of the different sources of uncertainty in the 'top down' impact study framework over multiple time horizons. The uncertainty from climate variability is addressed through the creation of a resampling methodology to be applied to global climate model outputs. Through resampling model precipitation, the direction of change for both mean monthly flows and flood quantiles are found to be uncertain with large possible ranges. Hydrological model parameter uncertainty is quantified using Monte Carlo methods to sample the model parameter space. Through sensitivity experiments, individual hydrological model parameters are shown to influence the magnitude of simulated flood quantile changes. If a larger number of climate scenarios are used, hydrological model parameter uncertainty is small only contributing up to 5% to the total range of impacts. The uncertainty in estimating design standard flood quantiles is quantified for the Generalised Pareto distribution. Flood frequency uncertainty is found to be most important for nearer time horizons, contributing up to 50% to the total range of climate change impacts. In catchments where flood estimation uncertainty is less important, global climate models are found to contribute the largest uncertainty in the nearer term, between 40% and 80% of the total range, with emissions scenarios becoming increasingly important from the 2050s onwards.

Shire of Murray has concerns regarding the negative impact that a 100 year flood could have on existing structures built before 1997. The increase cost in construction due to landfill has an adverse effect on development in Pinjarra. Feasibility of constructing a diversion channel at upstream of Murray River to attenuate the flood level from 1 in 100 year ARI to 1 in 50 year ARI, was investigated by Kiong (2003). The Murray River Water Surface Profile along three kilometres south of Greenlands Road was modelled. Flood damages on each flood occurrence were assessed and Average Annual Damage (AAD) was calculated. The AAD is used to estimate the monetary benefit against the construction cost of the diversion channel. Groundwater along Greenlands and Fauntleroy Drains was also modelled to determine the viable depth of the designed channel, as well as the analysis of backwater. The proposed channel is designed at different scenarios (invert level at breakout point, culvert or causeway design, and diversion channel variations). The benefit cost ratio of the proposed diversion channel is calculated. Other mitigation options are suggested including detention basins for structural measure, or building a new flood-proof township for non-structural measure.

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico
The river basin of the Peixe, a sub basin of the Alto Piranhas, with a dimension of 3. 443 km2 which gathers 18 municipalities in its lower course, suffers the phenomenon of flooding during the rainy season, causing the flooding of the cities of SÃo JoÃo do Rio do Peixe, Sousa, and Aparecida. This research aims to understanding the phenomenon from the relationships of the physical framework and geomorphological studies of a basin shape and the indices that are related to the laws of fluvial geomorphology, as well as the interrelationships between the physical substrate and precipitation through the interactions between watershed and atmospheric systems at synoptic, regional and local scales. The use of GIS software for the collection, modeling and analysis of the data was essential for the objectives of this work. The modeling of the maps using the gvSIG software, Arc GIS, Hidroflow make it possible to achieve the objectives linked to Hydrology and Climatology. The results shows the indices Kc, Kf and Ic, of 1.77, 0.19 and 0.31 respectively which states that the basin is not prone for flooding showing that other variables that causes flooding are present there. The results of observations shows that the climatological atmospheric systems operating in the analyzed event for the year 2008, the ITCZ ​​in conjunction with other systems on a regional scale, one Vortex Cyclonic Higher Level - VCAN or a Squall lines are responsible for the precipitation above climatology of the area. For the rainy pattern of the year (2008) the ITCZ ​​was the main atmospheric system, followed by VCANS DOLs and that coupled with the negative dipole, an ENSO episode of La NiÃa totaling only from January to May a precipitation above annual climatology. The analysis made by referring to the vegetation NDVI - Normalized Vegetation Index shows that there was considerable reduction in the SÃo JoÃo do Rio do Peixe and other areas of the basin, however it should be considered that there was a recovery in other areas especially in the mountains, which allows one to state that flooding can be related to assaults of removal of vegetation in the area of ​​ SÃo JoÃo do Rio do Peixe especially with the removal of riparian vegetation. The occupation of urban land in the cities of SÃo JoÃo do Rio do Peixe and Sousa shows that floods are related to the occupation of the river channel and as well as interventions in the drainage of small dams, dams on the river bed near the city hinder the flow of a larger volume when the aforementioned events.
A bacia hidrogrÃfica do rio do Peixe, uma sub bacia do rio Alto Piranhas, com uma dimensÃo de 3. 443 Km2 que congrega 18 municÃpios, no seu baixo curso sofre o fenÃmeno das inundaÃÃes quando no perÃodo chuvoso, inundando parte das cidades de SÃo JoÃo do rio do Peixe, Sousa e Aparecida. Essa pesquisa busca o entendimento do fenÃmeno pelas relaÃÃes do arcabouÃo fÃsico com os estudos geomorfolÃgicos da forma da bacia e de Ãndices que estÃo relacionados Ãs leis da geomorfologia fluvial, como tambÃm com as inter-relaÃÃes existentes entre o substrato fÃsico e as precipitaÃÃes, atravÃs das interaÃÃes entre a bacia hidrogrÃfica e os sistemas atmosfÃricos em escalas sinÃtica, regional e local. A utilizaÃÃo de software de geoprocessamento para a coleta, modelizaÃÃo e anÃlises dos dados foi fundamental para os objetivos deste trabalho. A modelagem dos mapas com utilizaÃÃo dos softwares Gvsig, Arc Giz, Hidroflow possibilitou alcanÃar os objetivos vinculados a Hidrologia e Climatologia. Os resultados encontrados mostram Ãndices Kc, Kf e Ic, respectivamente 1,77; 0,19 e 0,31 que afirma ser a bacia nÃo propensa a inundaÃÃes, o que demonstra que outras variÃveis causadoras das inundaÃÃes estÃo aà presentes. Os resultados das observaÃÃes climatolÃgicas mostram que os sistemas atmosfÃricos atuantes no evento analisado para o ano de 2008, que a ZCIT conjugado com outros sistemas em escala regional, um VÃrtice CiclÃnico de NÃvel Superior - VCAN ou com uma Linha de Instabilidade sÃo responsÃveis pelas precipitaÃÃes acima da climatologia da Ãrea. Para o ano padrÃo chuvoso (2008) a ZCIT foi o principal sistema atmosfÃrico, seguido dos VCANS e DOLs, que acoplado ao Dipolo Negativo, um ENOS de episÃdio de La NiÃa totalizando apenas de janeiro a maio precipitaÃÃes acima da climatologia anual. As anÃlises referentes a vegetaÃÃo feito por NDVI - Ãndice de VegetaÃÃo Normalizada mostra que houve reduÃÃo considerÃvel no SÃo JoÃo do rio do Peixe e em outras Ãreas da bacia, entretanto hà de se considerar que houve recuperaÃÃo em outras Ãreas principalmente nas serras, o que permite afirmar que as inundaÃÃes podem se relacionar com agressÃes da retirada da vegetaÃÃo na Ãrea de SÃo JoÃo do rio do Peixe, notadamente com a retirada da mata ciliar. A ocupaÃÃo do solo urbano das cidades de SÃo JoÃo do rio do Peixe e Sousa demonstra que as inundaÃÃes estÃo relacionadas com a ocupaÃÃo da calha do rio e bem como com as intervenÃÃes na drenagem, por pequenas barragens, barramentos no leito do rio prÃximo a cidade, dificultam o escoamento de um volume maior quando dos eventos supracitados.

Flooding has the potential to have significant impact on the value of properties depending on the level of inherent vulnerability. Experts argue that it is not the actual risk but the perception of risk among property holders that influences vulnerability of value. The hypothesis that changing perception of flood risk could make property value vulnerable in the market is the main focus of the research. This dimension of research has received very low attention in commercial property literature. The existing knowledge base of flooding and property value reveals that focus has been largely associated with residential properties. Conceptual understanding of the extent and scale of the effect of flooding on the vulnerability of property value of commercial properties would be worthwhile for relevant stakeholders. The research methodology follows a quantitative approach with sequential application: of literature review, conceptual model generation, data collection from primary and secondary sources with remote questionnaire survey of selected study areas in the UK. The conceptual model was operationalised using analysis and interpretation of the collected data and finally cross validated with secondary data gained from commercial real estate experts . The strength of this research lies in the conceptualisation of the subject matter of property value in the context of flood vulnerability. This work provides innovative conceptual insight towards business vulnerability and vulnerability of value. The variables contributing towards vulnerability were hierarchically ranked using both collected data and deductive methods. The patterns of impact and recovery analysis emphasized that within the commercial sector indirect effects of flooding should be given equal importance with direct damages. The implication of perception on the vulnerability of property value showed a slightly different picture from business vulnerability in the chosen study areas when differentiated based on flood experience. In a nutshell the study reflected that the commercial property sector does not take flooding as one of their priorities. This is in part due to differential attitude towards risk of the population within the flood plain based on their knowledge and experience of flooding. The perception of stakeholders towards vulnerability of value can change with increasing magnitude and severity of floods and it is possible that the implications on market value of commercial properties will be visible in the future. Practitioners and researchers will find this study useful in developing an understanding of the vulnerability of commercial property value in the context of changing flood risk.

Shire of Murray has concerns regarding the negative impact that a 100 year flood could have on existing structures built before 1997. The increase cost in construction due to landfill has an adverse effect on development in Pinjarra. Feasibility of constructing a diversion channel at upstream of Murray River to attenuate the flood level from 1 in 100 year ARI to 1 in 50 year ARI, was investigated by Kiong (2003). The Murray River Water Surface Profile along three kilometres south of Greenlands Road was modelled. Flood damages on each flood occurrence were assessed and Average Annual Damage (AAD) was calculated. The AAD is used to estimate the monetary benefit against the construction cost of the diversion channel. Groundwater along Greenlands and Fauntleroy Drains was also modelled to determine the viable depth of the designed channel, as well as the analysis of backwater. The proposed channel is designed at different scenarios (invert level at breakout point, culvert or causeway design, and diversion channel variations). The benefit cost ratio of the proposed diversion channel is calculated. Other mitigation options are suggested including detention basins for structural measure, or building a new flood-proof township for non-structural measure.

The study of urban climate has a great importance in regard to the understanding of the human-nature relationship and the interaction between the local climate and the city. This expectation motivated this study on the Urban Climate in the city of Bragança, Pará State, a city that has undergone urban impacts from the rains that cause floods and flooding that hit several areas of the city, especially along the course from the Cereja stream, that is cutting the urban mesh. The Floods are one of the most serious problems which affects the cities when there is an occurrence of extreme precipitation events, generating impacts that affect the daily routine of the people. In this way, the choice for the study of meteoric impact of the channel, the third channel among the subsystems of the Urban Climate System (SCU), it is justified by the study of floods and flooding that happened in the city and the need to understanding the environmental conditions that originate. In this context, this study aimed to analyze the urban climate and extreme expectation events associated with the occurrence of floods and flooding in the urban area of Bragança. Therewith, we analyzed the occurrence of floods in Cereja stream and flooding in Bragança in 2004-2013 period; It was analyzed the variability of precipitation in urban areas from January to May, in 2014; we identified the atmospheric systems linked to extreme expectation events in the urban area of the city; however, the balance of participation of climate systems during the Amazon winter 2014 and it was made a map of climate risk in areas of extreme rainfall situations with sight to urban land use planning in the city. Therefore, the research was based on the SCU theory developed by Monteiro (1976). In the historic flood (2004-2013) were found 32 extreme events, that only 07 were classified as episodes of relevance for this study due to the impact of records in the urban area. The weather data analyzed was collected of the Weather Station Conventional of Tracuateua city (EMT) and Automatic Weather Station of Bragança (EMB) that belongs to INMET and a network of 07 rain gauges installed in the urban area of the city in 2014 which allowed a development of variability maps precipitation during the Amazon winter. Were also it was developed participation swing charts of atmospheric systems with satellite images from GOES 13 aid provided by INPE and Letters daily Synoptic of 00h and 12h provided by the Navy of Brazil. With the results, it was observed that the ZCIT has increased the participation in the occurrence of extreme events and urban impacts, and it was noted that there is a great variability of expectation in the study of the area, up to 161 mm between the northnortheast sector (Rainier) and the South-southwest sector (less rain). Finally we prepared a risk map as a tool for urban land in use planning, considering the local climate variable.
O estudo do clima urbano é de grande importância no que se refere à compreensão da relação homem-natureza e da interação entre o clima local e a cidade. Essa perspectiva motivou este estudo sobre o Clima Urbano de Bragança/PA, cidade que tem sofrido impactos urbanos oriundos das chuvas que provocam inundações e alagamentos que atingem diversas áreas da cidade, principalmente, ao longo do curso do Igarapé Cereja, que corta a malha urbana. As inundações são um dos graves problemas que afetam as cidades quando há ocorrência de eventos de precipitação extrema, gerando impactos que influenciam no cotidiano das populações. Nesse sentido, a escolha pelo estudo do canal do Impacto Meteórico, terceiro canal dentre os subsistemas do Sistema Clima Urbano (SCU), justifica-se pelo estudo das inundações e alagamentos que tem ocorrido em Bragança e pela necessidade de entendimento das condições climáticas que as originam. Nesse contexto, este trabalho teve como objetivo geral analisar o clima urbano e os eventos de precipitação extrema associados à ocorrência de inundações e alagamentos na área urbana de Bragança-PA. Com isso, analisou-se a ocorrência de inundações no Igarapé Cereja e alagamentos em Bragança no período de 2004-2013; analisou-se a variabilidade da precipitação na área urbana no período de janeiro à maio do ano de 2014; identificou-se os sistemas atmosféricos ligados aos eventos de precipitação extrema na área urbana de Bragança-PA; realizou-se o balanço de participação dos sistemas atmosféricos durante o inverno amazônico de 2014 e elaborou-se um mapa de áreas de risco climático em situações de extrema precipitação com vistas ao ordenamento territorial urbano do município. Para tanto, a pesquisa baseou-se na teoria do SCU elaborada por Monteiro (1976). No histórico de inundações (2004-2013) foram encontrados 32 eventos extremos, dos quais apenas 07 foram classificados como episódios de relevância para este estudo, devido aos registros de repercussão na área urbana. Os dados meteorológicos analisados foram coletados da Estação Meteorológica Convencional de Tracuateua (EMT) e Estação Meteorológica Automática de Bragança (EMB), pertencente ao INMET e por uma rede de 07 pluviômetros instalados na área urbana de Bragança/PA em 2014, que possibilitou elaboração de mapas da variabilidade da precipitação durante o inverno amazônico. Foram também elaborados gráficos de balanço de participação mensal dos sistemas atmosféricos, com auxílio de imagens do satélite GOES 13 disponibilizadas pelo INPE e Cartas Sinóticas diárias das 00h e 12h disponibilizadas pela Marinha do Brasil. Com os resultados, observou-se que a ZCIT tem maior participação na ocorrência de eventos extremos e impactos urbanos, além de observar-se que há uma grande variabilidade da precipitação na área de estudo, de até 161 mm entre o setor norte-nordeste (mais chuvoso) e o setor Sul-sudoeste (menos chuvoso). Por fim foi elaborado um mapa de riscos como instrumento para o ordenamento territorial urbano, considerando a variável climática local.

O aumento da inundação em áreas do baixo curso do rio Taquari, no Pantanal do estado do Mato Grosso do Sul, tem transformado a pecuária desta região numa atividade com baixa rentabilidade, à medida que extensas áreas de campo passaram a ser inundadas vários meses durante o ano a partir da década de 70. A pecuária realizada em campos naturais de regiões úmidas do Pantanal indica que há necessidade de se investigar metodologias apropriadas para avaliação de impacto ambiental, que abordem impactos diretos, indiretos, cumulativos e processos do meio físico que alteram, de maneira prejudicial, o meio ambiente. Supõe-se que a inundação na planície do rio Taquari esteja relacionada com a ocupação antrópica nas áreas de planalto da bacia do rio Taquari. O presente trabalho tem por objetivo avaliar os impactos ambientais na planície de inundação do baixo curso do Taquari, decorrentes da ocupação antrópica da bacia hidrográfica do rio Taquari em sua totalidade, considerando os impactos ambientais causados pela pecuária à medida que se configura como principal atividade econômica da bacia bem como os processos erosivos e de assoreamento no quadro atual do regime de inundações. As etapas de caracterização da área, de análise dos impactos e as propostas de ações mitigadoras, previstas num Estudo de Impacto Ambiental, foram aqui analisadas. Foram utilizadas informações sobre as características do meio físico, biótico e socioeconômico, selecionadas a partir do levantamento dos dados existentes com recorte efetuado para a bacia hidrográfica do rio Taquari. Na maior parte dos temas, este foi um processo de levantamento, ordenamento e recuperação de informações, na escala original de 1:250.000, do Plano de Conservação da Bacia do Alto Paraguai-PCBAP, gerenciado no SPRING. Foram também realizadas viagens de campo para a complementação dos dados e para o levantamento de atividades antrópicas com verificações \"in loco\" da ocorrência de impacto ambiental. A maioria dos dados socioeconômicos compilados para o presente trabalho teve por base os censos agropecuários e demográficos realizados pelo IBGE. Os resultados obtidos demonstram que os impactos ambientais decorrentes da pecuária no planalto interferem no regime de inundação na planície da bacia, o que só foi possível de ser identificado a partir de análises integradas em toda a bacia hidrográfica do rio Taquari. Verificou-se que os métodos de EIA são adequados para identificar os impactos diretos decorrentes da pecuária, mas não são adequados para identificar os processos e seus efeitos cumulativos na extensão da bacia hidrográfica do rio Taquari. Além disto, a abordagem da avaliação ambiental estratégica, como procedimento para análise ambiental em políticas, planos e programas, mostra-se adequada para as análises na BHRT à medida que está centralizada nos efeitos do ambiente sobre as necessidades e oportunidades de desenvolvimento. Contudo, somente a recuperação de danos ambientais, o controle das origens dos impactos no ambiente e um sistema de gestão consciente de seus compromissos podem levar, juntamente com a melhora dos procedimentos técnicos e administrativos para análises ambientais, à uma maior proximidade da sustentabilidade ambiental na BHRT.
The increase of flooding in the low course areas of Taquari river in the Pantanal - Mato Grosso do Sul state, has been transforming the cattle raising activity to a low profit activity in the region, when that extensive areas of pasture started to be flooded throughout several months a year from the 1970s. Since these areas are located in the Pantanal region where cattle raising activity is carried on in natural pasture it is necessary to investigate suitable methodologies for evaluation of the ambiental impact, approaching direct, indirect and cummulative impact as well as the processes that change, in a harmful way the environment. The flooding in the floodplain in Taquari river is supposed to be related to the anthropic ocupation in the upland areas of the Taquari river watershed. This work aims to evaluate the environmental impact caused by the anthropic ocupation, the cattle raising activity in the basin and the erosion and silting process in the flood plain of the Taquari river low course. The steps for the area characterization, the analysis of the impact and proposals viewing to diminish the problem, projected in an EIA (Environmental Impact Study), were also considered here. Information on the physical, biologic and socio-economic environment, selected from pre existent data survey, carried on for the Taquari river watershed (BHRT) were used here. For most of the themes, this was a process of surveying and recovering information in the original scale of 1:250.000 from the PCBAP managed in the SPRING GIS model. Field work to complement the existent data to survey the environmental impact of anthropic activities were also carried on. Most of socio-economic data used here were based on the cattle raising activity and demographic census data from IBGE. The results show that the environmental impact caused by cattle raising in the upland interferes in the flooding system in the watershed flood plain, and this fact could only be identified from the integrated analysis of the whole Taquari river watershed. It was observed that the EIA methods are suitable to identify the direct impact caused by the cattle raising activity, but they are not suitable to identify the process and its cummulative effects along the Taquari river watershed. Moreover, it was observed that the approach of the Strategic Environmental Assessment (SEA) as a procedure for environmental analysis in the policies, plans and programs is suitable for the analysis in the BHRT when it is centralized in the effects of environment on the necessities and opportunities of development. However, only the recovering of ambiental damage, the control of the effects caused by impacts on the environment and a system of conscient management can lead to an improvement in the technic and administrative procedures for a really possible ambiental sustentability in the BHRT.

Tree cores of Fraxinus pennsylvanica were used in a dendrochronological analysis investigating the species' responses to climate and flooding. The objective was to develop a model that incorporates the effects of precipitation, temperature, and flooding on radial growth in this species in north-central Texas. The trees exhibited strong climatic signals. The study clearly shows that all three factors have significant impacts on tree ring growth both prior to and during growth; however, the nature and extent of these impacts are highly dependent on what time of year they occur. The large temporal variations in growth responses emphasize the importance of considering the timing of environmental events when studying tree growth responses.

In 2008 flooding occurred over a majority of Iowa, damaging homes, displacing residents, and taking lives. In the wake of this event, the Iowa Flood Center (IFC) was charged with the investigation of distributed flood mitigation strategies to reduce the frequency and magnitude of peak flows in Iowa. This dissertation is part of the several studies developed by the IFC and focused on the application of a coupled physics based modeling platform, to quantify the coupled benefits of distributed flood mitigation strategies on the reduction of peak flows in an agricultural watershed. Additional investigation into tile drainage and terraces, illustrated the hydrologic impact of each commonly applied agricultural practice. The effect of each practice was represented in numerical simulations through a parameter adjustment. Systems were analyzed at the field scale, to estimate representative parameters, and applied at the watershed scale. The impact of distributed flood mitigation wetlands reduced peak flows by 4 % to 17 % at the outlet of a 45 km2 watershed. Variability in reduction was a product of antecedent soil moisture, 24-hour design storm total depth, and initial structural storage capacity. The highest peak flow reductions occurred in scenarios with dry soil, empty project storage, and low rainfall depths. Peak flow reductions were estimated to dissipate beyond a total drainage area of 200 km2, approximately 2 km downstream of the small watershed outlet. A numerical tracer analysis identified the contribution of tile drainage to stream flow (QT/Q) which varied between 6 % and 71 % through an annual cycle. QT/Q responded directly to meteorological forcing. Precipitation driven events produced a strong positive logarithmic correlation between QT/Q and drainage area. The addition of precipitation into the system saturated near surface soils, increased lateral soil water movement, and reduced the contribution of instream tile flow. A negative logarithmic trend in QT/Q to drainage area persisted in non-event durations. Simulated gradient terraces reduced and delayed peak flows in subcatchments of less than 3 km2 of drainage area. The hydrographs were shifted responding to rainfall later than non-terraced scenarios, while retaining the total volumetric outflow over longer time periods. The effects of dense terrace systems quickly dissipated, and found to be inconsequential at a drainage area of 45 km2. Beyond the analysis of individual agricultural features, this work assembled a framework to analyze the feature at the field scale for implementation at the watershed scale. It showed large scale simulations reproduce field scale results well. The product of this work was, a systematic hydrologic characterization of distributed flood mitigation structures, pattern tile drainage, and terrace systems facilitating the simulation of each practices in a physically-based coupled surface-subsurface model.

Two-phase flow, ubiquitous to waterflood oil recovery, geological CO2 storage, and groundwater remediation, is strongly influenced by wettability, and made more complex under mixed-wet conditions. Optimum wettability for such operations is not well established due to limited experimental data and difficulties in their interpretation. This thesis investigates the impact of mixed-wettability, characterised by advancing contact angle θa on capillary pressure, relative permeability, and waterflood displacement. Using a Darcy scale simulator, relative permeability kr, capillary pressure Pc, and residual oil saturation Sor were extracted by history matching production and pressure drop data from centrifuge brine invasion and waterflood displacements completed for a range of θa. As θa increased, a larger |Pc| was required to displace oil from mixed-wet cores at high initial oil saturation. End point oil and brine permeability decreased with increasing θa. A permeability enhancement, such that kr > 1, was measured both when the flowing phase was wetting and non-wetting and was attributed to a slippage at the oil/brine interface directly correlated to θa. Residual oil saturation decreased monotonically with increasing θa while core-averaged remaining oil saturation at the end of the waterflood exhibited a non-monotonic dependence on θa. Simulations of the waterfloods revealed that both significant capillary end effects and premature termination of the waterflood in the laboratory contribute to the deviation between remaining and residual saturations. This work demonstrates that the former is not representative of the latter, as it has been assumed in a number of studies in the literature. Both corefloods and microfluidic waterfloods show the importance of combining experimental studies with simulation for correct interpretation of the measurements especially under capillary dominated flow.

O estudo apresentado fundamenta-se no evento extremo ocorrido em março de 1967, na Bacia do Rio Santo Antônio, no Município de Caraguatatuba, Brasil, tendo por objetivo esclarecer os reais impactos do fenômeno de debris flows, ou corridas de detritos, produzido por precipitações intensas. Os riscos intangíveis de vítimas humanas e tangíveis de danos materiais associados a tal evento na região são muito maiores nos dias de hoje, devido ao crescimento demográfico e à implantação de grandes empreendimentos industriais, como os do setor petrolífero, com reduzidos e, muitas vezes inexistentes, sistemas de defesa. Considerando tais fatores, a região necessita de estudos detalhados que possibilitem a elaboração de planos diretores mais eficazes, com objetivas diretrizes para a tomada de decisões, planos de contingência, regulação da distribuição da população, medidas estruturais mitigadoras e remediadoras. Para chegar aos resultados do estudo, foi definido o modelo digital do terreno a partir de análises topográficas, geográficas, hidrográficas e de uso e ocupação do território. A simulação de um evento similar ao ocorrido em 1967 resultou em valiosas informações para a definição de planos de evacuação, diretrizes de zoneamento, critérios de desmobilização, planos diretores para o município e implantação de obras de defesa.
The study here proposed aims to define the real impacts of the debris flows phenomenona, caused by a very intense rainfall, based on the disaster occurred in March of 1967, in Caraguatatuba, Brazil. The risk regarding mainly human casualties and material losses associated to such events in the region is higher nowadays, due to the increasing population rates and the settling of large companies such as oil industry, with reduced defense measures and works. Considering these factors, the region needs more detailed studies that will enable more effective master plans, decision making guidelines, contingency plans, population distribution regulation and structures of mitigation and remediation. In order to achieve these results, it was defined a digital terrain model through analysis of topographic, geographic, hydrographic and soil occupation data. The simulation of a similar extreme event as of 1967\'s on this model will result in valuable information to define evacuation plans, zoning guidelines, demobilization criteria, master plans and structural defenses.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
The intense population growth of the last decades has shown the lack of urban planning of brazilian cities. The disordered urbanization process involves directly in increased impervious areas, changing natural conditions and interfering in hydrological cycle. The metropolitan area of the João Pessoa city, Paraíba, has suffered from urban expansion without urban planning and has seen various impacts, such as floods. In the region of the river Cuiá basin, located in southern coastline of Paraíba, in the municipality of João Pessoa, between the UTM coordinates 9.210.000N/302.000E e 9200.00N/292.000E, such events have been repeated in periods of heavier rainfall. In this sense, the application of hydrological models has been recommended for prediction of impacts on water resources and assists in the decision making of managers. Thus, this study aims to estimate the impacts of urbanization on flooding in the river Cuiá basin. For this, we used the hydrological models IPH II and HEC-RAS and considered three urbanization scenarios (current, trend and critic), defined based on certain percentages of soil sealing and urban occupation. The rainfall-runoff simulations were performed considering rainfall with return period of 10, 50 and 100 years allowed us to estimate the impacts on the flows generated, on peak times and on floodplains of the basin. With the simulation results, it was found that the lower frequency rainfall results in peak flow up to 80% higher than the highest frequency. Under the same conditions, peak times were reduced on average by 10% when compared to the critical and current scenarios. The flood simulations generated information that allowed create the flood maps. Considering the potencial of flood scenarios more critical and less frequent events, floodplains can be as much as 13% higher than in the current scenario.
O intenso crescimento populacional das ultimas décadas tem evidenciado a falta de planejamento urbano das cidades brasileiras. O processo de urbanização desordenado implica diretamente no aumento de áreas impermeáveis, modificando condições naturais do meio e interferindo no ciclo hidrológico. A região metropolitana da cidade de João Pessoa, Paraíba, tem sofrido com a expansão urbana sem planejamento e, por consequência, visualizado vários impactos, como as inundações e os alagamentos. Na bacia hidrográfica do rio Cuiá, localizada no sul do litoral paraibano, no município de João Pessoa, entre as coordenadas UTM 9.210.000N/302.000E e 9200.00N/292.000E, eventos desse tipo são constantemente verificados nos períodos de chuvas mais intensas. Nesses casos, a aplicação de modelos hidrológicos tem sido recomendada para previsão dos impactos sobre os recursos hídricos e auxiliar no processo de tomada de decisão por parte dos gestores. Nesse sentido, este estudo tem como objetivo estimar os impactos da urbanização sobre as inundações urbanas na bacia hidrográfica do rio Cuiá. Para isso, utilizou-se os modelos hidrológicos IPH II e HEC-RAS, considerando três cenários de urbanização (atual, tendencial e crítico), definidos com base em percentuais de impermeabilização do solo e de áreas de ocupação urbana. As simulações chuva-vazão foram realizadas considerando chuvas com tempos de retorno de 10, 50 e 100 anos e permitiram estimar os impactos sobre as vazões geradas, sobre os tempos de pico e sobre áreas inundáveis da bacia. Com os resultados das simulações, verificou-se que as vazões máximas foram até 80% maiores quando resultantes de chuvas de menor frequência, do que de maior frequência. Nessas mesmas condições, o tempo do pico foi reduzido, em média, em 10% quando comparados os cenários crítico e atual. As simulações das inundações geraram informações que permitiram confeccionar os mapas de inundações. Ao se considerar o potencial das inundações nos cenários mais críticos e para eventos menos frequentes, as áreas inundáveis podem chegar a ser até 13% maiores do que no cenário atual.

O grande crescimento urbano, industrial e agrícola das cidades em toda a região de Taubaté, influi na qualidade da água do rio Paraíba do Sul. Considerando sua importância na qualidade de vida da população, no desenvolvimento econômico e na sustentabilidade ambiental, se faz necessário manter controle mais rígido da qualidade da água do rio. Neste estudo, foram analisados atributos físico-químicos da água utilizada pela cultura do arroz e da água do rio Paraíba do Sul na região. As analises foram feitas durante o cultivo do arroz. Os resultados mostraram que a prática do cultivo do arroz favoreceu o aumento do nível de poluição do rio Paraíba do Sul. O cultivo de arroz carreou fertilizante e matéria orgânica para dentro do rio evidenciando a necessidade da adequação da adubação para produção sob inundação.
The great urban, industrial and agricultural growth of the cities across Taubaté region influences water quality of Paraíba do Sul river. It is necessary to keep more rigid river water quality control, considering its importance in healthy quality life of the population, economic development and environmental sustainability. In this study, we analyzed physical and chemical attributes of rice cultivation water and Paraiba do Sul river water from Taubaté region. The analysis was made during the rice cultivation. The results showed that the practice of rice cultivation favored the increase pollution level of Paraíba do Sul river. The rice cultivation adduced fertilizer and organic matter into the river showing that the fertilization needs to be adjusted to production under flooding.

Non-point pollution from stormwater runoff is one of the greatest threats to water quality in the United States today, particularly in urban karst settings. In these settings, the use of karst features and injection wells for stormwater management results in virtually untreated water being directed into the karst aquifer. Currently, no policies exist specifically to provide water quality protections to karst environments. This study utilized a combination of karst stormwater quality data, along with survey data collected from MS4 Phase II communities, and an analysis of current federal, local, and state water quality regulations, to assess the need for karst-specific water quality regulations. Water quality data indicate that significant levels of contamination are mobilized during storm events, and often are directed into the karst system via Class V injection wells. Survey data collected from MS4 stakeholders in the karst regions of Kentucky indicate stakeholders are generally unable to explain local karst regulations or the steps taken to develop them. This confusion comes in part from insufficient progress on evaluation criteria available for the MS4 Minimum Control Measures (MCMs). Karst waters are often placed into the legal “gray zone” due in part to differences in definitions of key terms in state and federal regulations. This study recommends the development of regulations specific to karst waters at the state and federal levels through either the adaptation of existing or creation of new policies, which place an emphasis on the integration of water quality monitoring and karst education.

This thesis investigates the effectiveness of Low Impact Development Infrastructure (LIDI) and Green Infrastructure (GI) in reducing flooding resulting from heavy rainfall events and sea-level rise, and in improving stormwater quality in the City of Miami Beach (CMB). InfoSWMM was used to simulate the 5, 10, and 100-year, 24-hour storm events, total suspended solids (TSS), biochemical oxygen demand (BOD), and chemical oxygen demand (COD) loadings, and in evaluating the potential of selected LIDI and GI solutions in North Shore neighborhood. Post-development results revealed a decrease of 48%, 46%, and 39% in runoff, a decrease of 57%, 60%, and 62% in TSS, a decrease of 82%, 82%, and 84% in BOD, and a decrease of 69%, 69%, and 70% in COD loadings. SWMM 5.1 was also used to simulate the king tide effect in a cross section in Indian Creek Drive. The proposed design simulations successfully demonstrated the potential to control flooding, showing that innovative technologies offer the city opportunities to cope with climate impacts. This study should be most helpful to the CMB to support its management of flooding under any adaptation scenarios that may possibly result from climate changes. Flooding could be again caused as a result of changes in inland flooding from precipitation patterns or from sea-level rise or both.

A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfillment of the requirements for the degree of Master of Science. School of Geography, Archaeology and Environmental Studies (GAES). Johannesburg, October 2017.
Climate and weather-related impacts have become widespread particularly affecting the tourism industry. Changes in the climate and weather lead to changes in tourist seasons, products and travel opportunities. Flooding has gained research attention over the past decade, since the destruction creates many challenges for tourism businesses. Floods are a growing global problem, increasing in terms of frequency of occurrence, property damages, business economic losses, and fatalities. South Africa has begun to experience many annual flood events both coastal and in-land, but the Limpopo Province has been declared as flood disaster area, since the increase in temperatures and precipitation. Interest now lies on how particular tourist destinations in the Limpopo Province can adapt to reduce flooding risks whilst increasing opportunities mainly for the economy. Debates around flooding costs, recovery processes, and adaptive capacities affirm to be more challenging for the tourism accommodation sector. The study aimed to explore the perceived flooding impacts on different types of tourist accommodation. Thus, to determine if floods hindered any tourist bookings, offerings, and tourist length of stay. The exploration verified the possible flood risks to vulnerable accommodation and no adequate adaptation plans. A purposeful sample of 145 tourist accommodation businesses located across three flood-prone regions of the Limpopo Province were selected to answer a semi-structured questionnaire to put across their flooding experiences from a management perspective. The semi-structured questionnaire was combined with telephone interviews and email responses. Coherent theme development within the theoretical framework was achieved through content analysis. Content analysis allowed for the critical discussion of deductive and inductive themes found in the results. Floods during peak-seasons threaten and affect tourist accommodation, leaving them behind in business. Those not affected benefit with increased tourist demand and new opportunities in the hospitality industry. Tourist accommodation businesses are exposed to flood risks and experience challenges to assess, recover and adapt from the direct and indirect impacts. Alongside the destruction of tourism in these regions, were concerns of the provision of flood mapping and flood management plans for tourism businesses. Wider flooding impacts on the environment and the surrounding local communities demonstrates a growing problem for the future. Key words: floods; tourist accommodation; flooding impacts; risks; opportunities; tourist demand; adaptation; flood recovery, flood mapping, flood management plans.
LG2018

A research report submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Science (Geography and Environmental Studies) at the School of Geography, Archaeology & Environmental Studies. Johannesburg, 24 February 2018.
The extensive and frequent flood events in the Shashe-Limpopo confluence area provide an opportunity to investigate the impacts of such an extreme event in terms of vegetation cover. Extreme flooding events are expected to occur more frequently as a consequence of climate change. Understanding the impacts of flood events on vegetation dynamic would be very useful to develop a dynamic simulation model that can predict the woody species composition of water retention areas or restored floodplains on the basis of flooding characteristics and therefore proposed riverine forest and landscape planning and management. This study used Landsat 7 data to quantify the response of vegetation to flood events in the Shashe-Limpopo confluence area. Two flood events that occurred in 2000 and 2013 respectively were analysed to evaluate the patterns of vegetation response in the area of study. Different indices such as NDVI, NDWI and Modified NDWI (MNDWI) were tested in mapping vegetation patterns and the flood extent. The MNDWI was shown to be more effective in extracting water information than the NDWI. NDVI results and change detection statistical change showed efficiency in indicating vegetation response to floods. The results show that using MNDWI and a 0.2 threshold value, water delineation is possible. Vegetation shows that it flourishes after the floods however; there is some degree of change. The results derived from this can be able to help with landscape planning and management.
LG2018

Increasing global mean temperature or global warming has the potential to affect the hydrologic cycle. In the 21st century, according to the UN Intergovernmental Panel on Climate Change (IPCC), alterations in the frequency and magnitude of high intensity rainfall events are very likely. Increasing trend of urbanization across the globe is also noticeable, simultaneously. These changes will have a great impact on water infrastructure as well as environment in urban areas. One of the impacts may be the increase in frequency and extent of flooding. India, in the recent years, has witnessed a number of urban floods that have resulted in huge economic losses, an instance being the flooding of Mumbai in July, 2005. To prevent catastrophic damages due to floods, it has become increasingly important to understand the likely changes in extreme rainfall in future, its effect on the urban drainage system, and the measures that can be taken to prevent or reduce the damage due to floods. Reliable estimation of future design rainfall intensity accounting for uncertainties due to climate change is an important research issue. In this context, rainfall intensity-duration-frequency (IDF) relationships are one of the most extensively used hydrologic tools in planning, design and operation of various drainage related infrastructures in urban areas. There is, thus, a need for a study that investigates the potential effects of climate change on IDF relationships. The main aim of the research reported in this thesis is to investigate the effect of climate change on Intensity-Duration-Frequency relationship in an urban area. The rainfall in Bangalore City is used as a case study to demonstrate the applications of the methodologies developed in the research Ahead of studying the future changes, it is essential to investigate the signature of changes in the observed hydrological and climatological data series. Initially, the yearly mean temperature records are studied to find out the signature of global warming. It is observed that the temperature of Bangalore City shows an evidence of warming trend at a statistical confidence level of 99.9 %, and that warming effect is visible in terms of increase of minimum temperature at a rate higher than that of maximum temperature. Interdependence studies between temperature and extreme rainfall reveal that up to a certain range, increase in temperature intensifies short term rainfall intensities at a rate more than the average rainfall. From these two findings, it is clear that short duration rainfall intensities may intensify in the future due to global warming and urban heat island effect. The possible urbanization signatures in the extreme rainfall in terms of intensification in the evening and weekends are also inferred, although inconclusively. The IDF relationships are developed with historical data and changes in the long term daily rainfall extreme characteristics are studied. Multidecedal oscillations in the daily rainfall extreme series are also examined. Further, non-parametric trend analyses of various indices of extreme rainfall are carried out to confirm that there is a trend of increase in extreme rainfall amount and frequency, and therefore it is essential to the study the effects of climate change on the IDF relationships of the Bangalore City. Estimation of future changes in rainfall at hydrological scale generally relies on simulations of future climate provided by Global Climate Models (GCMs). Due to spatial and temporal resolution mismatch, GCM results need to be downscaled to get the information at station scale and at time resolutions necessary in the context of urban flooding. The downscaling of extreme rainfall characteristics in an urban station scale pose the following challenges: (1) downscaling methodology should be efficient enough to simulate rainfall at the tail of rainfall distribution (e.g., annual maximum rainfall), (2) downscaling at hourly or up to a few minutes temporal resolution is required, and (3) various uncertainties such as GCM uncertainties, future scenario uncertainties and uncertainties due to various statistical methodologies need to be addressed. For overcoming the first challenge, a stochastic rainfall generator is developed for spatial downscaling of GCM precipitation flux information to station scale to get the daily annual maximum rainfall series (AMRS). Although Regional Climate Models (RCMs) are meant to simulate precipitation at regional scales, they fail to simulate extreme events accurately. Transfer function based methods and weather typing techniques are also generally inefficient in simulating the extreme events. Due to its stochastic nature, rainfall generator is better suited for extreme event generation. An algorithm for stochastic simulation of rainfall, which simulates both the mean and extreme rainfall satisfactorily, is developed in the thesis and used for future projection of rainfall by perturbing the parameters of the rainfall generator for the future time periods. In this study, instead of using the customary two states (rain/dry) Markov chain, a three state hybrid Markov chain is developed. The three states used in the Markov chain are: dry day, moderate rain day and heavy rain day. The model first decides whether a day is dry or rainy, like the traditional weather generator (WGEN) using two transition probabilities, probabilities of a rain day following a dry day (P01), and a rain day following a rain day (P11). Then, the state of a rain day is further classified as a moderate rain day or a heavy rain day. For this purpose, rainfall above 90th percentile value of the non-zero precipitation distribution is termed as a heavy rain day. The state of a day is assigned based on transition probabilities (probabilities of a rain day following a dry day (P01), and a rain day following a rain day (P11)) and a uniform random number. The rainfall amount is generated by Monte Carlo method for the moderate and heavy rain days separately. Two different gamma distributions are fitted for the moderate and heavy rain days. Segregating the rain days into two different classes improves the process of generation of extreme rainfall. For overcoming the second challenge, i.e. requirement of temporal scales, the daily scale IDF ordinates are disaggregated into hourly and sub-hourly durations. Disaggregating continuous rainfall time series at sub-hourly scale requires continuous rainfall data at a fine scale (15 minute), which is not available for most of the Indian rain gauge stations. Hence, scale invariance properties of extreme rainfall time series over various rainfall durations are investigated through scaling behavior of the non-central moments (NCMs) of generalized extreme value (GEV) distribution. The scale invariance properties of extreme rainfall time series are then used to disaggregate the distributional properties of daily rainfall to hourly and sub-hourly scale. Assuming the scaling relationships as stationary, future sub-hourly and hourly IDF relationships are developed. Uncertainties associated with the climate change impacts arise due to existence of several GCMs developed by different institutes across the globe, climate simulations available for different representative concentration pathway (RCP) scenarios, and the diverse statistical techniques available for downscaling. Downscaled output from a single GCM with a single emission scenario represents only a single trajectory of all possible future climate realizations and cannot be representative of the full extent of climate change. Therefore, a comprehensive assessment of future projections should use the collective information from an ensemble of GCM simulations. In this study, 26 different GCMs and 4 RCP scenarios are taken into account to come up with a range of IDF curves at different future time periods. Reliability ensemble averaging (REA) method is used for obtaining weighted average from the ensemble of projections. Scenario uncertainty is not addressed in this study. Two different downscaling techniques (viz., delta change and stochastic rainfall generator) are used to assess the uncertainty due to downscaling techniques. From the results, it can be concluded that the delta change method under-estimated the extreme rainfall compared to the rainfall generator approach. This study also confirms that the delta change method is not suitable for impact studies related to changes in extreme events, similar to some earlier studies. Thus, mean IDF relationships for three different future extreme events, similar to some earlier studies. Thus, mean IDF relationships for three different future periods and four RCP scenarios are simulated using rainfall generator, scaling GEV method, and REA method. The results suggest that the shorter duration rainfall will invigorate more due to climate change. The change is likely to be in the range of 20% to 80%, in the rainfall intensities across all durations. Finally, future projected rainfall intensities are used to investigate the possible impact of climate change in the existing drainage system of the Challaghatta valley in the Bangalore City by running the Storm Water Management Model (SWMM) for historical period, and the best and the worst case scenario for three future time period of 2021–2050, 2051–2080 and 2071–2100. The results indicate that the existing drainage is inadequate for current condition as well as for future scenarios. The number of nodes flooded will increase as the time period increases, and a huge change in runoff volume is projected. The modifications of the drainage system are suggested by providing storage pond for storing the excess high speed runoff in order to restrict the width of the drain The main research contribution of this thesis thus comes from an analysis of trends of extreme rainfall in an urban area followed by projecting changes in the IDF relationships under climate change scenarios and quantifying uncertainties in the projections.

The seasonal periodicity of hydrology, physical and chemical water quality parameters and phytoplanktonic assemblages was studied at two sites in a large tropical Australian riverine impoundment. This study, the first in the lower Fitzroy River at Rockhampton, occurred between August 1990 and November 1993. It covered extremes in riverine flow conditions including major flooding and drought.

The annual flow regime was characterized by major flows in the "wet" season (summer and autumn) and greatly reduced or no flow in the "dry" season of winter, spring and sometimes early summer. Consequently, the thermal regime at both of the study sites was divided into two phases. The first was a phase of water column heating in the late winter to early summer. Features of this heating phase were long term stratification with progressive epilimnetic deepening, high pH, regular occurrence of epilimnetic oxygen supersaturation and decreased or undetectable levels of oxidized nitrogen in the surface layer. Hypolimnetic anoxia was recorded late in this phase. The second, between substantial wet season inflows and late winter was characterized by nutrient rich inflows and water column cooling and mixing.

Distinct interannual differences occurred in the volume, source and timing of inflows and subsequent water chemistry. In 1991, conductivity, water clarity, filterable reactive phosphorus (FRP) and pH increased markedly following major flooding from northern tributaries, while oxidized nitrogen decreased. This was in marked contrast to the drier years of 1992 and 1993 where turbidity and oxidized nitrogen were higher during the initial post-flood period and conductivity and FRP were lower. Extremes of mostly abiogenic turbidity (range 1.6 to 159 NTU) were a feature of the light climate. Ratios of euphotic depth/mixing depth below 0.3 occurred in early 1992 and 1993.

Steep gradients in the physical and chemical environment were paralleled by variations in the phytoplankton. Algal biomass (as chlorophyll a) at Site 1, midstream opposite the water intake for the city of Rockhampton, ranged from 1.5 to 56.6 ug L-1. The vertical water column distribution of chlorophyll was variable with assemblages normally dominated by phytoflagellates and various species of cyanoprokaryotes. There was also higher relative abundance of chlorophyll a (reflecting increasing dominance of cyanoprokaryotes) in the latter half of the year and at the lower end of light availability. The specific vertical water column positioning with respect to light and temperature is shown for assemblages dominated by the genera Anabaena, Aphanizomenon and Cylindrospermopsis.

The most striking aspect of the phytoplankton was the long term dominance of cyanoprokaryotes and the species richness (particularly that of cyanoprokaryotes) when compared with the dearth of information to date on other tropical rivers. Seasonal successions were varied. Regularly occurring assemblages were cyanoprokaryotes (Oscillatoriales), euglenophytes or non-flagellated chlorophytes during flows followed by flagellated chlorophytes and then cyanoprokaryotes (Nostocales) during the dry season. Genera present indicated highly eutrophic conditions. Hierarchical agglomerative clustering of phytoplankton data and comparison with a principal components analysis of corresponding environmental data were used to demonstrate the linkage between steep environmental gradients and variation in the phytoplankton assemblage. The specific environmental conditions associated with the success of various species were also analysed and presented. Using the above information, a two-part model was proposed which predicts the most likely genera of phytoplankton with respect to multidimensional environmental gradients. This model covers a wide gamut of conditions varying from highly variable lotic to lentic environments.

As Cylindrospermopsis raciborskii was considered a most important species in relation to the quality of the water supply for Rockhampton, the physical, chemical and biotic conditions prior to and during a bloom of this species are described. A number of possible grazers of C. raciborskii were identified with a view to future biomanipulation. One of these, the large ciliate, Paramecium cf. caudatum was found to be an effective grazer of toxic straight C. raciborskii in the laboratory.

This study is unique in that it analyses the impact of episodic events (eg. major flooding) on the subsequent phytoplankton in the lower Fitzroy River. The model relating phytoplankton to multidimensional environmental gradients provides great information for use in management, particularly in relation to the prediction of toxic algal blooms.

The objective of this research was to determine whether the use of polymer compounds with elastic properties can reduce residual oil saturation in porous media below that of brine or inelastic polymerized solutions. One hypothesis is that long-chain polymer molecules experience stress and a resulting strain when they flow through pore throat constrictions. If the fluid residence time in larger pore spaces is insufficient to allow full relaxation, then strain can accumulate. Sufficient strain results in normal forces which can impinge on oil interfaces and potentially mobilize them. A second hypothesis suggests that polymerized solutions can temporarily protect flowing oil filaments from snap off, allowing them to flow longer and de-saturate further than they would otherwise. The approach taken in this thesis was to conduct a series of core floods in several different sandstones using displacement fluids with elasticity ranging from none to those with extremely high relaxation times. Accelerated flow rate was also employed to reduce residence time and maximize the accumulation of elastic strain and normal force potential. Experiments were designed to provide direct comparisons between both non-elastic and elastic floods but also multiple floods with increasing elasticity. The results were inconclusive with some experiments showing additional oil recovery that could be attributed to elastic mechanisms. Most experiments, however, showed no significant difference between elastic and non-elastic floods when experimental parameters were controlled within narrow limits. This research did refine the experimental context in which elastic effects are most likely to be observed. As such, it can serve as a precursor to additional core flooding in oil-wet systems, experiments conducted at reservoir temperature, and those where the pressure gradient of the flood is held constant and the flow rate allowed to vary. Computer aided tomography could also be employed to visualize the mobilization of oil with different displacement fluids, identify where bypassed oil occurs with unstable floods, and determine how oil is subsequently mobilized with better conformance and or elasticity.
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Although the global energy demand is shifting towards a well-balanced energy mix, fossil fuels will continue to have a significant role in this transition and will maintain a big share in the energy mix portfolio. The production of oil and gas has already reached the apex in the time that most of the conventional giant reservoirs are depleting, and discoveries for new reserves have shrunk down. In conventional reservoirs, it is estimated that about two-thirds of the Original Oil in Place (OOIP) will not be produced within the field lifecycle, corresponding to an average Recovery Factor (RF) between 20% and 40%. This low recovery factors from traditional methods trigger more investments in the Enhanced Oil Recovery (EOR) techniques. Waterflooding is one of the most commonly used technique to increase RF by raising or maintaining reservoir pressure. Lack of comprehending the driving forces in Naturally Fractured Reservoirs and reservoir heterogeneity may lead to serious conformance problems in which dealing with excessive undesirable water production becomes very challenging. Chemical EOR through an injection of a polymer solution is amongst the tested options that can be used to improve sweep efficiency. Ultimately, understanding the reservoir characteristics and having the know-how to implement the best recovery option will help to maximize the field’s lifecycle and increase the RF. Therefore, this study investigates some key elements that have a significant influence on the overall fluid flow behavior. The work reveals insights on the impact of capillarity and wettability in heterogeneous porous media. An experimental lab-scale consisting of a 2D sandbox model, which mimics a water-wet fractured system with injection and production ports, was designed, fabricated, and tested in single-phase and two-phase flow scenarios including the injection of water and polymer solutions. In the case of single-phase flow, a waterflood baseline scenario was studied with controlled variables, which helped to distinguish the contrast with the polymer flood case. Implementing water injection in a fractured water-wet reservoir showed that water prefers to channel through high permeable streaks, which consequently leads to poor volumetric sweep leading to significant bypassed zones. Investigating the two-phase flow was the essence of this research. Thus, the same procedures were repeated where water and polymer were used to displace oil. During waterflooding, due to strong capillarity contrast between the matrix and fracture media, flow divergence was found to be faster towards the matrix medium where the matrix gets saturated faster than that the fracture, overriding the high permeability of the fracture. Whereas, polymer flooding exhibited better volumetric sweep in all scenarios. Numerical simulations were used to replicate the experiments. This work can give new visual insights about key recovery mechanisms in heterogeneous reservoirs using polymers.

碩士
國立成功大學
都市計劃學系
104
The frequency and the scale of flooding have been increasing due to climate change and urban expansion. To reduce runoff events, low-impact development (LID) is the green approach for reducing the area of impervious surface and managing storm water at the source with decentralized micro-scale control measures. However, the current LID assessment and practical applications in Taiwan are mainly at the community and household scales. As for urban design, the current applications ignore the diversity and complexity of the urban built environments, such as different densities, positive and negative spaces, volumes of building and so on. The assessment of current practice is more often assess the run-off mitigation of individual site, but seldom use basin as the scope of the assessment. It ignores the physiographic and hydrological factor; hence the application of LID cannot reflect flood mitigation effectiveness of the whole city. Looking toward to enable LID to strength the link with urban design to reduce the runoff in coping urban flooding, the research use physiographic inundation model to evaluate the flood mitigation effectiveness. Then, through correlation analysis, explore whether the improving flooding volume is related to its building environment and its location. Finally, simulate and analyze the influences of runoff route. The research shows that LID strategies will have different effect under different location and implementation objects. It is to say it will have better effect under specific condition. The assessment information can be the foundation to set the target of LID strategies and can helps to enact regulations of LID strategies in flooding resilience urban design more suitable for every different type of built environments, and can achieve the best benefit of flood mitigation effectiveness of the city.

Thesis (MPH.) -- University of Limpopo, 2015
Introduction: A qualitative study was undertaken to assess the impact that flooding of the Okavango river have on the health of the community of Sepopa village. Aim: To assess the impact that flooding of the Okavango River has on the health of the community of Sepopa village. Study: the study was conducted in the village of Sepopa within the community aged between fifteen years and above. The village has an estimated population of 2824. Method: A non experimental descriptive research design using qualitative approach was used. Sampling: Two types of sampling procedure were used, being simple random sampling and purposive sampling. Results: The study revealed that 85% of the respondents reported or suffered from the injuries due to high waters brought about by floods, 92% reported to have fallen sick or having a member of their family who was sick with conditions related to floods. Of all the respondents, 54% explained they heard of deaths occurring in a river either due to drowning or crocodile and hippopotamus attacks. Lastly, 8% of respondents reported they never heard of any injuries, illness or death due to the impacts of floods. Conclusion: It can thus be concluded that the river has an impact to the health of the community either before, during and after a flood event, activities may be undertaken by the population at risk, by policy makers and by emergency responders to reduce health risks. Proper planning aimed to reduce the harmful effects of flooding by limiting the impact of a flood on human health and economic infrastructure should be adopted. Key words: health, sepopa village, impact, Okavango river.

Flooding inundation during hurricanes has been very costly and dangerous. However, the impact of climate change on hurricane flooding is not well understood at present. As sea surface temperatures increase, it is expected that hurricane intensity will increase and sea levels will rise. It is further hypothesized that climate change will increase hurricane flooding inundation, which would increase property damages and adversely affect a greater number of people. This thesis presents a case study of Corpus Christi, Texas, which analyzes the impact of climate change on hurricane flooding. Sea level rise projections and intensification of historical hurricanes were considered in this study. Storm surges were determined with the ADCIRC numerical model, while GIS was used to estimate area flooded, property damages, and population affected. Flooding inundation, property damages, and number of people affected by flooding increases as the intensity of the hurricane increases. As hurricane intensity increases and sea levels rise, the depth of flooding also increases dramatically. Based on two historical hurricanes and one shifted historical hurricane, on average the inundated area increases about 11 km2 per degree Celsius of sea surface temperature rise, the property damages increase by about $110 million per degree Celsius of sea surface temperature rise, and the number of people affected by flooding inundation increases by about 4,900 per degree Celsius of sea surface temperature rise. These results indicate that it may become necessary to consider the effects of climate change when building future coastal communities and adapting the protection of existing communities.

碩士
南臺科技大學
企業管理系
107
Residential flooding will endanger the safety of homes, and will also cause loss of household property. The larger the flooded area near the home, the inconvenience may be caused to the convenience and health of the households. Therefore, the flooding trend of homes is for home buyers. Words are the decision-making factors of evasiveness and have an absolutely negative impact on the value of the house. In the past, research on flooding and housing prices mostly focused on the impact of housing flooding (in flooded areas) on housing prices, and rarely conducted empirical research on how housing flooding areas affect housing prices, and rarely targeted flooding. The possible frequency (flooding caused by the daily rainfall of several millimeters) is to explore the impact of this flooding trend on house prices. In this study, the possible frequency of flooding is divided into high frequency (200 mm daily rainfall) and low frequency (350 mm daily rainfall), according to the depth of flooding 30~50 mm, 50~100. Three types of flooding intensity, such as millimeters and 100 millimeters, are based on Tainan City. The QGIS geographic information system is used to analyze the real-time price of the real estate transaction of the Ministry of the Interior from October 1, 1998 to September 30, 105. Age, construction type, parking space, transfer floor, transfer floor square, number of rooms, number of halls, number of guards, main building materials, management organization and other variables are control variables, to explore whether the residential price and housing are in the flooded area, The relationship between the coverage area of ​​flooded area within 500 meters of residential radius. The results show that the flooding caused by the two kinds of rainfall intensity is located in the 50-100 mm flooded area, which has a significant negative effect on house prices. The home is located in the flooded area of ​​30~50 mm or more. There is no significant relationship; under the flooding intensity of 30~100 mm, the coverage of flooded area within 500 meters of residential radius is significantly negatively correlated, that is, within 500 meters of residential radius under other conditions. The greater the coverage area of ​​flooded water, the lower the residential price.

碩士
國立高雄師範大學
生物科技系
96
This research aims to investigate the species diversity of freshwater snails in Wu-gou village in Pingtung County, and the flooding impacts on its community structures, including the proportional abundance, the abundance of the dominant species. From March 2005 to February 2006, 7120 individuals of freshwater snails ,belonged to 9 , were collected. The duration of this survey is divided into four stages, including pre-disturbance, disturbance, post-disturbance Ⅰ, and post-disturbance Ⅱ. The results indicate that the species richness, abundance, and Shannon-Wiener Diversity Index decreased after the flooding disturbance. Although all these biological measurements recover gradually after flooding, the recovery of abundance is the most evident, which greater than the of pre-disturbance period. In most sites, proportional abundance of freshwater snail were varied from pre-disturbance after flooding. Despite their abundance dropped due to flooding, the collected individuals of dominant species recover to its pre-disturbance period within 1-3 months after flooding. Dynamic variation in abundance rank of most freshwater snails were recorded in most site during disturbance period; concordance species rank in abundance were shown in 6-9 month after flooding. Overall, flooding demonstrate a short-term but significant impact on the community structure of freshwater snails in Wu-gou village. Ranks of Proportional individuals, dominant species, and abundance all could varied during the flooding period and 6 months after disturbance. However, in 6-9months after flood, community structure of freshwater snails in Wu-gou village all similar to the pre-disturbance period.

碩士
國立臺灣大學
歷史學研究所
102
Yilan, located at the northeast of Taiwan, is nestled right between the mountains and the sea. It is isolated, and its terrain goes from high in the west to low in the east. The Yilan Chuoshui River (now Lanyang River) that runs through the middle, along with the alluvial fan and delta that the river flows through forms the principle topography of the Yilan Plain. Yilan is prone to rain, regardless if it is from summer typhoons, or the rains brought by the northeast monsoons of winter. They all bring about large amounts of water to the region. Whenever the rainfall suddenly intensifies the Lanyang River has the potential to flood, leading to diversions of the downstream rivers and causing low-lying areas to nearly turn into a postdiluvian world. The earliest aborigines to inhabit the Yilan Plain were the Kavalans, who had an extremely strong affinity for water. Living scatted over the watery Yilan Plains, the fishing, hunting, sailing and trade that made up their livelihoods all arose from a direct dependency on the water. In the first year of the Emperor Jiaqing of the Ch’ing dynasty’s reign (1796), Han Chinese began to settle and cultivate land in the Yilan Plains. The agricultural lifestyle of Han Chinese settlers was completely different from that of the Kavalans, and with their superior agricultural skills, the Han Chinese gradually became the more powerful ethnic group of the plains. Han Chinese hamlets developed along the areas under cultivation; however, when torrential rain approached, floods broke out bringing a large amount of sand, completely burying entire areas. This caused great loss of life and property in many Han Chinese hamlets. This paper first analyzes and discusses the natural and cultural background behind the ease of Yilan to suffer from flooding, with emphasis placed on the relationship between the people and their geographical surroundings. The effects on Yilan brought by flooding were great, and records of flooding began from the Ch’ing dynasty. However, due to limitations in technological ability, there was quite a lack of Ch’ing era flooding prevention in Yilan. Through the modernization brought by the power of the colonial government during the Japanese colonial period, colonial authorities in Taiwan began to construct levees along the Yilan Chuoshui River. Since then, residents along the banks of the river have been able to reduce the hardship brought by floods. Yet, due to the topography and climate of the Yilan Plains, the levees are unable to completely eradicate flooding. As a result, residents along the banks of the river still harbor a fear of flooding. Among Yilan residents, they refer to the flooding invading their land as “tso-tu&;#257;-tsui” (“invading floods”). Moreover, the historical memory of “tso-tu&;#257;-tsui” exists forever within the hearts and minds of the residents, which we can discover from memoirs, literary works, and oral history. The second focal point of discussion in this paper looks at how the people of Yilan made use of rituals in their popular religion to respond to flooding. This paper takes the Shengou area on the north bank of the Lanyang River as an example, entering the discussion from Han Chinese water beliefs. By going into the Shengou area to conduct field research, and making use of oral interviews and recorded “pai-poh” (ceremonies involving praying on the levees), this paper aims to analyze the significance behind the belief in malicious spirits and flood rituals in local areas that suffer from floods. The people of Yilan live in an unstable environment brought about in no small measure by the hardships of flooding. The development and construction of this area is interdependent with the flooding situation of the area. This paper observes and studies flood related rituals, and we can see that the people of Yilan themselves are a part of nature. Through the earliest popular religion of making sacrificial offering to the gods, they attempted to dispel the menace and fear brought about by flooding to the area, while at the same time sought to reach a balance with nature.

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.

Preliminary reconnaissance undertaken in summer 2013 identified the scale of stormwater management issues in Xiamen, having frequent storm events that overwhelm the stormwater and sewer infrastructure resulting in widespread flooding. This research explored the role that green facilities play in addressing stormwater issues through the inquiry of Low Impact Development strategies and techniques. From a long-term perspective, green infrastructure planning and implementation is inevitably linked with strong education programs, rational stormwater codes and regulations, a variety of financing and incentives, as well as an integrated and competent administration system. This research presents a design proposal for green infrastructure retrofit for a selected study block in the central area of Xiamen to help guide water sensitive urban design and development in the future. Seven recommendations based on the synthesis of the literature review, key-informant interviews, built-project studies and the retrofit design proposal are proposed. This document will be submitted to Xiamen Urban Planning & Design Institute for considerations to be integrated in city master planning policy and zoning codes and standards as needed and to inform a demonstration project to help advance long-term strategies and recommendations.
October 2015

碩士
國立臺灣大學
生物環境系統工程學研究所
107
In recent years, due to climate change and extreme weather events, the rainfall intensity has increased. This phenomenon also has the same trend in summer typhoons, which increases the frequency of flooding disasters. At present, the flooding simulation usually sets up a single rainfall station for model simulation. Although this method is faster and simpler to construct, the single rainfall station may not be able to represent the rainfall situation of a whole area. In addition, the drainage method in the metropolitan area usually collects rainwater from the inlet and the side ditch. If the garbage and the fallen leaves accumulate due to heavy rainfall, the water inlet will not reach the designed water collecting effect, which may cause the metropolitan area the product of flooding. In this study, we investigated the effects of rainfall data from different spatial distributions on flooding simulations in urban areas, using rainfall observation data and radar echo data to simulate flooding. Comparison of single rainfall station, multi-rainfall station Thiessen''s Method rainfall setting, multi-rainfall station Thiessen''s Method Partition rainfall setting, Inverse Distance Weighted rainfall and radar echo rainfall. Through the methods of Accuracy (ACC), Probability of Detection (POD), Threat Score (TS), Precision or Predictive value (PPV), it is estimated that what kind of rainfall setting has better performance for flooding simulation in the urban area. Then set different clogging rates to compare the clogging rate values closer to the real city blockage, and compare the clogging rates with the Taipei city flooding map. In this study, Jieshang drainage and Hougang drainage basin in Shilin Distrinct, Taipei, is selected as the study area. Two short duration and one long duration rainfall events are used for simulation and analysis. Due to the closeness to real rainfall collection phenomena, the simulated results from Inverse Distance Weighted rainfall setting has a better agreement whether the duration of rainfall event is short or long. And set different clogging rate to get the clogging factor 20% as the closest to the real urban area clogging rate. It is also comparable to the flooding simulation map of Taipei City. The result of setting a 20% clogging rate can make the indicators have better performance.

Houston's Fifth Ward neighborhood is one of the last remaining areas of the inner city to have not yet seen large-scale redevelopment. Situated just northeast of downtown, the neighborhood's population is predominantly low- to mid-income African Americans; demographics are similar today as they were during the neighborhood's prime, from the 1920s-60s, when the Fifth Ward was a cultural hub of Houston famous for its musical culture of zydeco and blues. The ward's rich history also has dark spots, however, specifically its longstanding reputation as a center of poverty and violent crime, and its physical vulnerability to damaging floods. Much of the neighborhood's built history is unpreserved and unprotected, at risk of being wiped off the map by both development interests and extreme weather events. By modernizing the city's approach to stormwater management and infrastructure and strengthening its historic preservation and emergency management practices, Houston could help preserve one of its oldest communities, while also decreasing flood volumes, improving air and water quality, saving money, and establishing a pattern of smart growth citywide. In addition, neighborhood level efforts to promote placemaking via preservation and sustainability efforts can help the Fifth Ward leverage the redevelopment process to change its reputation, ensuring a future for the community that respects its past.
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