The leading cause of bridge failure has often been identified as bridge scour, which is generally defined as the erosion or removal of streambed and/or bank material around bridge foundations due to flowing water. These scour critical bridges are particularly vulnerable during extreme flood events, and pose a major risk to human life, transportation infrastructure, and economic sustainability. Climate change is increasing the intensity and persistence of large flow events throughout the world, further straining bridge infrastructure. Retrofitting the thousands of undersized and scour critical bridges to more rigorous standards is prohibitively expensive, and current countermeasures inadequately address the core problems related to bridge scour. This research tested the efficacy of using approach embankments as intentional sacrificial "fuses" to protect the integrity of bridges with minimal damage during large flow events by allowing the streams to access their natural floodplain and reduce channel velocities. The concept was evaluated using the Hydrologic Engineering Center's River Analysis System (HEC-RAS) models. Steady flow models were developed for three specific bridges on two river reaches. Bayesian streamflow return period estimators were developed for both river reaches using available United States Geological Survey (USGS) stream gauge data to evaluate sacrificial embankments under non-stationary climatic conditions. Fuse placement was determined to be a cost effective scour mitigation strategy for bridges with suboptimal hydraulic capacity and unknown or shallow foundations. Additional benefits of fuses include reductions in upstream flood stage and velocity.

Master of Landscape Architecture / Department of Landscape Architecture/Regional and Community Planning / Tim Keane / Wildcat Creek in Riley County, KS has repeatedly flooded in the past 5 years causing significant damage to the watershed, private property, and community livelihood. Strategically placing wetlands throughout the watershed can help reduce stormwater runoff, increase infiltration, and increase wildlife habitat. A watershed assessment was completed to determine the best location for wetlands in the Wildcat Creek Basin. Two watershed-scale plans for wetlands were derived and evaluated based upon estimation of stormwater runoff and quality of wildlife habitat. Wetlands were then examined and incorporated into existing land cover and land uses at the site-scale for an existing golf course. Three proposals for the nine hole course (for best golf experience, wildlife habitat, and wetland creation) were developed to reflect expansion options from a Par 30 to a Par 34 or 35 course. Each proposal was evaluated based on wetland capacity from estimated stormwater runoff, quality of wildlife habitat, playability of the golf course for all skill levels, and cost of implementation. After this evaluation, the wetland proposal was moved forward and further developed into a proposal that is best suited for the site. Following wetland implementation, stormwater runoff can be collected on-site to prevent runoff and flooding at the golf course and downstream. In order to solve flooding problems in the Wildcat Creek watershed, a series of wetlands can be implemented at the smaller site scale, like the Wildcat Creek Golf Course site, throughout the watershed. Wetlands are one component of a larger stormwater management system that is needed to reduce flooding of the Wildcat Creek and the flood-prone area of Manhattan, KS.

Master of Regional and Community Planning / Department of Landscape Architecture and Regional and Community Planning / Tim Keane / The City of Manhattan, Kansas has been subject to intense flooding in the last couple of years. Areas of the city, within the Wildcat Creek Watershed, have been adversely affected. The City of Manhattan and stakeholders from various walks of life are looking for solutions to alleviate flooding within the area. This Master’s Project looks into rainwater harvesting as one of the solutions to help reduce stormwater runoff and contribute to the alleviation of flooding within the Watershed. Rainwater harvesting is increasingly being recognized as an effective way to reduce stormwater runoff. The project explores the potential benefit of using a network of rainwater harvesting elements, namely rain barrels and cisterns supplemented by rain gardens and other infiltration methods to reduce runoff in the City of Manhattan, Kansas. To assess the benefit of using rainwater harvesting in the City, a neighborhood scale site was chosen and divided into land use types. Three phases were used to assess the impact and implementation of rainwater harvesting. Phase I calculates the volume of runoff generated from each land use type and how much of that runoff can be harvested from the rooftops. The values from the neighborhood scale analysis were then extrapolated to see the impact of rainwater harvesting on a larger scale. Phase II looks at the configuration of a rainwater harvesting system for the structures in each land use type and rainwater reuse options. Finally, Phase III looks at policies, regulations and incentives that can be employed by the City of Manhattan to help encourage rainwater harvesting. This Master’s project seeks to educate the City and its residents about the benefits of rainwater harvesting as a stormwater management tool and provide steps towards potentially using rainwater harvesting as a way to reduce runoff, and help alleviate flooding in the Wildcat Creek Watershed.

Master of Landscape Architecture / Department of Landscape Architecture/Regional and Community Planning / Timothy Keane / The City of Manhattan, Kansas is looking for possible solutions to mitigate flooding along Wildcat Creek within the Wildcat Creek Watershed. Recent flooding has caused substantial property damage. The project presented here brings recreation into the community by designing a golf course in a location along Wildcat Creek that addresses flooding issues, increases infiltration, and improves water quality. The golf industry has a long way to go to become more sustainable. The world is facing many challenges related to water and hydrology. Much of the opposition towards the golf industry is because critics see it as environmentally unfriendly. Golf has the potential to become a catalyst for change in the way we design and develop the landscape around us. The golf industry can become a leader in sustainable design while taking on hydrological concerns within the community. This project demonstrates the application of a golf course to help mitigate flooding along Wildcat Creek with the use of vulnerability and suitability analysis as a guide to site selection. This method of analysis illustrates the process of identifying and protecting areas vulnerable to degradation by designing a golf course in a suitable location to utilize water hazards to store flood water, provide more floodplain access to effectively increase infiltration capacity, reduce runoff rates, and improve water quality. The report explains the relationship between golf course design and environmental practices as they relate to hydrology on a theoretical site in Manhattan, Kansas. By integrating golf course design theory and environmentally sound stormwater management practices, water hazards on the golf course can become the fundamental elements used in strategizing the design of the golf course. A conceptual plan was created to maximize the infiltration capacity of the site as well as allow increased floodplain access, and provide a place to store flood water. A golf course can then be properly sited and designed hydrologically around the use of water hazards to help reduce flooding and improve water quality within the watershed.

St. Bernard Parish (Louisiana) has undergone a transition from rural, agrarian characteristics to that of a suburban, industrial based community. Its fragile environment has been substantially altered by man's use. Planning and development strategies need to be devised to address the stress placed on the environment by these alterations, particularly dealing with coastal erosion, land loss and increased threat of tidal surge and flooding if development in the area is to continue. St. Bernard also faces a changing economy with the declines of its industrial based economy and employment base which requires that new forms of economic development are established to replace jobs those that have been lost. This thesis addresses these issues and proposes actions that could be taken to learn from the errors of the past to attempt to mitigate losses that have occurred by emphasizing planning and arranging priorities to create an agenda for the future which provides economic development and controlled growth within the bounds of Saint Bernard Parish's environmental capacity.

Este trabalho tem por objetivo estudar as regiões dos canais catódicos de uma célula a combustível de membrana polimérica condutora de prótons PEM unitária, em que há acúmulo de água e os padrões de escoamento desta água nos canais, bem como as condições de operação em que isto ocorre. Esta água acumulada nos canais catódicos tem duas origens distintas, a saber: 1. água produzida na reação de redução do oxigênio no sítio catalítico do cátodo, 2. água de condensação formada a partir do vapor de água proveniente do umidificador de oxigênio. O arranjo experimental desenvolvido permitiu a perfeita visualização dos fenômenos; a saber: iniciando-se com gotículas que emergem da camada de difusão gasosa do cátodo, passando estas gotículas a se aglutinarem por um processo de coalescimento aumentando de tamanho até formarem um filme nas paredes dos canais. Em continuidade a este processo há um adensamento do filme com a formação de bolsões (slugs) de água líquida que ocupam a área de passagem do oxigênio nos canais. O bloqueio da passagem do oxigênio pelo bolsão de água líquida no canal impede que o oxigênio alcance os sítios catalíticos da camada catalítica do cátodo onde ocorre a reação de redução do oxigênio, cessando desta forma a reação, constituindo-se num dos mais sérios problemas das células a combustível do tipo membrana polimérica, uma vez que afeta diretamente o desempenho da célula. A formação contínua desses slugs e seu agrupamento é um fenômeno denominado de encharcamento (flooding) da célula. Para se observar estes fenômenos que ocorrem no interior dos canais catódicos utilizou-se de um protótipo de célula a combustível transparente unitária de 5 cm² de área geométrica cuja placa de fechamento foi feita de policarbonato transparente. A célula foi alimentada com o combustível hidrogênio pelo lado do ânodo e com o oxidante oxigênio pelo lado do cátodo. Nos experimentos utilizou-se um espectro de temperaturas variando de 25ºC a 55ºC. A temperatura máxima da célula ficou limitada a 55ºC uma vez que o policarbonato começa a se degradar com água a 60ºC por isso não se utilizando temperaturas na faixa de 70ºC a 90ºC que são as temperaturas de operação das células PEM comerciais. As vazões de oxigênio e de hidrogênio usadas foram de 60 mL min-1 e de 100 mL min-1 respectivamente. A faixa de potencial variou de 0,1 V a 1,0 V. Foram utilizados cargas de platina de 0,4 mg cm-2 no eletrodo anódico e no eletrodo catódico. Os resultados experimentais foram comparados aos resultados numéricos na forma de curvas de polarização que medem o desempenho da célula apresentando uma boa concordância entre si, deste modo validando o modelo numérico usado. Para fazer a modelagem matemática da placa com os canais catódicos usou-se o software comercial COMSOL Multiphysics 4.3a, no qual se implementou uma função chave que indica o equilíbrio líquido/vapor, obtendo-se como resultados numéricos a distribuição de saturação em um espectro de temperaturas de 25ºC a 55ºC e de potenciais de 0,1 V a 1,0 V. / This work aims to study the regions of the cathode channels of a proton exchange membrane fuel cell PEMFC, in which there is accumulation of water, this water flow patterns in the channels, as well as the operating conditions at which this occurs. This accumulated water in the cathode channels has two distinct origins, namely: 1. Water formed in the reaction of the oxygen reduction at the cathode catalytic site. 2. Water from the condensation formed due to the water vapor coming from the oxygen humidifier. The developed experimental setup allowed the perfect visualization of the phenomena, as it follows: starting with droplets that emerge from the cathode gas diffusion layer, then these droplets undergo a process of coalescence, increasing in size to form a film on the walls of the channels. Continuing this process, there is a thickening of the film with the formation of liquid water slugs, occupying the area of the oxygen passage in the channels. Blocking the passage of the oxygen through the slug of liquid water in the channel prevents oxygen from reaching the catalytic sites of the cathode catalyst layer, where the oxygen reduction reaction occurs. Thereby, the reaction is stopped, constituting one of the most serious problems of the proton exchange membrane fuel cell, since the cell performance is directly affected. Continuous formation of these slugs and their grouping is a phenomenon called flooding of the cell. The study of these phenomena inside the cathodic channel of a transparent prototype PEM fuel cell (the end of the cathode plate constructed of polycarbonate, which is a transparent material), with 5 cm ² geometric area, was used. The cell was fed with hydrogen fuel at the anode and with oxidant oxygen at the cathode. In the experiments, a range of temperatures varying from 25ºC to 55ºC was used. The maximum temperature of the cell was limited to 55ºC, once the polycarbonate starts to degrade with water at 60ºC, therefore not using temperatures between 70ºC and 90ºC, which are the operating temperatures of commercial PEM fuel cells . The flow rates of oxygen and hydrogen commonly used were, respectively, 60 mL min-1 and 100 mL min-1. The potential range varied from 0.1 V to 1.0 V. Anodic and cathodic electrodes, with platinum loading of 0.4 mg cm-2, were used. The experimental results were compared with the numerical results in the form of polarization curves that measure cell performance, having good agreement with each other and, thereby, validating the numerical model used. The mathematical modeling of the cathode side, a COMSOL Multiphysics 4.3a commercial software was used, in which a switch function was implemented, which indicates the liquid / vapor equilibrium. Numerical results, as the distribution of saturation and the distribution of the water mole fraction, in a range of temperatures from 25ºC to 55ºC and potential of 0.1 V to 1.0 V, were obtained.

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.

Plantas típicas de regiões alagáveis tendem a apresentar diversas estratégias morfológicas e fisiológicas a fim de otimizar as chances de sobrevivência nestes ambientes. Um dos principais mecanismos, porém menos estudados, é a plasticidade encontrada no metabolismo de carboidratos que está diretamente ligado a alta demanda energética inerente a estes locais. Senna reticulata (Leguminosae) é uma espécie pioneira típica de planícies sujeitas ao regime anual de inundação da Amazônia Central, considerada uma das mais eficientes colonizadoras destes ambientes, além de extremamente tolerante ao alagamento. Neste trabalho, pela primeira vez foram caracterizados os padrões de reserva e de mobilização de açúcares desta espécie no período que corresponde ao seu estabelecimento no início da sua primeira fase terrestre. Adicionalmente o efeito da elevada concentração de gás carbônico foi verificada cultivando-se as plantas em câmaras de topo aberto (OTCs) em concentrações de CO2 ambiente (~380 µmol) e elevado (~760 µmol). Foram realizadas coletas destrutivas para análises de conteúdo de carboidratos não estruturais ao longo de 90 dias e ao longo de 24 horas. Foi verificado que S. reticulata possui altos níveis de amido foliar indicando que essa reserva pode estar diretamente relacionada a estratégia de constante produções de novas folhas que esta espécie apresenta. As razões sacarose:monossacarídeos se apresentaram altas em todos os órgãos analisados especialmente na raiz indicando que esta espécie pode apresentar estratégias metabólicas relacionadas também a estação seca pois além da sacarose poder ser utilizada como principal substrato na formação de raízes adventícias em condições de alagamento, também pode ser útil na regulação osmótica da raiz em locais com solos que apresentam baixa disponibilidade hídrica. A elevada concentração de gás carbônico promoveu um aumento significativo das reservas de amido na folha e no caule além de diminuir a taxa de degradação de amido transitório durante o período noturno. As concentrações de açúcares solúveis (glicose, frutose e sacarose) apresentaram tendência de diminuição sob condições de atmosfera enriquecida provavelmente devido à maior utilização dos mesmos para o crescimento da raiz. Este conjunto de respostas indica que essa espécie responde de forma positiva a elevada concentração de gás carbônico utilizando-se de possíveis mecanismos que diminuem a sinalização mediada por açúcares como, por exemplo, a habilidade de aumentar a capacidade de seus drenos já existentes, promovendo a mobilização do excesso de carboidratos para reservas e crescimento. / Plants of floodplains tend to show many morphological and physiological strategies to get higher survival rates in this places. One of them but with received less attention is the plasticity showed by carbohydrate metabolism that is directly linked to high energy demand at this sites. Senna reticulata (Leguminosae) is a pioneer tree which is common in floodplains sites submitted to an annual pulse of flooding at Central Amazonian and one of the most efficient colonizers at this sites besides extremely flooding tolerant. In this work by the first time was made the characterization about reserves and mobilizations patterns of sugars on the time range that corresponding to the establishment at the initial first terrestrial phase. Additionally, the effect of high CO2 was checked by growing plants in Open-Top-Chambers (OTC´s) with ambient (~380 µmol) and elevated (~760 µmol) CO2 concentrations. It was made systematic harvests along periods of 24 hours and 90 days to determinate the carbohydrate non-structural content. It was founded that S. reticulata had higher levels of starch in leaves showing evidences that this reserve is directly linked with constantly production of new leaves strategy. The ratio sucrose:monosaccharides was high in all organs but specially in roots showing evidences that this specie has metabolic strategies also related with drought periods because besides sucrose could be used as the aim substrate to adventitious root formation at flooding conditions and can be useful too on the osmotic regulation of roots in sites with low moisture content soil. The high levels of carbon dioxide promote significative increase of starch in leaves and stem besides decrease the degradation rate of transitory starch in leaves in the dark period. The levels of soluble sugars (glucose, frutose and sucrose) showed tendency of decrease under high CO2 conditions probably due to higher use in root growth. This set of answers evidence that this tree has positively response to high CO2 useful by possible mechanisms that decrease the signaling through sugars like for example the big abiliity of increase capacity of preexistents sinks to promoting the surplus carbohydrates mobilization to reserves and growth.

Este trabalho apresenta uma nova proposta metodológica de previsão de enchentes: o Modelo de Alerta Hidrológico com Base Participativa (MAHP). O MAHP consiste em um modelo de previsão de enchentes em bacias urbanas que integra Informações Geográficas Voluntárias (VGI) e redes de sensores sem fio (WSN). A principal contribuição deste modelo é o uso de dados de fontes heterogêneas (sensores aliados a dados fornecidos por voluntários) com o objetivo de reduzir a incerteza na previsão de enchentes. O modelo MAHP foi dividido em módulos, cada um deles é responsável por uma atividade no processo de previsão de enchentes. Embora o modelo possua diversos módulos auxiliares, pode-se resumir o modelo MAHP em três módulos principais: aquisição de dados; previsão de precipitações e, por fim, o módulo responsável pela previsão das enchentes. Para o módulo de aquisição de dados foram desenvolvidas metodologias para uso de dados voluntários de nível da água e sensores medidores de nível foram instalados para a composição da rede de sensores sem fio em pontos estratégicos nos canais fluviais da cidade. No módulo de previsão da precipitação do modelo MAHP foram desenvolvidos dois softwares de previsão, sendo um modelo de previsão da precipitação conceitual e um empírico. Para o funcionamento do módulo responsável pela previsão das enchentes foi feita a modelagem da bacia urbana de São Carlos no modelo SWMM (Storm Water Management Model). As simulações chuva-vazão realizadas com a bacia modelada apresentaram ajustes satisfatórios quando comparadas com eventos de enchente reais. Como o uso de informações voluntárias na previsão de enchentes é um conceito bastante novo, outra importante contribuição do trabalho foi propor parâmetros espaço-temporais que influenciam na qualidade da previsão ocasionada pelo uso de dados VGI. Existem vários cenários e combinações de uso de informações voluntárias que podem influenciar na previsão de enchentes. Neste trabalho foi considerada apenas uma destas combinações. Devido à ausência de dados VGI reais em eventos de enchente recentes foram utilizados dados de nível medidos por sensores para simular dados voluntários. Foram levantadas diversas hipóteses para que a inserção de dados voluntários no modelo MAHP tenham maior influência na redução da incerteza na previsão de enchentes. / This work presents a new approach forflood forecasting: Hydrological Alert Model with Participatory Base (HAMPB). The HAMPB consists of a flood forecasting model applied to urban basins integrating Volunteered Geographic Information (VGI) and Wireless Sensor Networks (WSN). The main contribution of this model is the use of heterogeneous data sources (convencional sensors and volunteered data) aiming to reduce the uncertainty in the flood forecasting. The HAMPB model was divided in modules, which are responsible for the forecasting process activities. Although the model has multiple auxiliary modules, we can summarize the HAMPB model in three modules: data acquisition; rainfall forecasting and, finally, the module responsible for flood forecasting. Telemetric water level sensors were installed at strategic points in river channels of the city to create the WSN. In order to use the volunteered information, a methodology was proposed tdevelop the acquisition module. The rainfall forecasting module consists of two forecasting models: an empirical model and a conceptual model. The conceptual prediction model presented closest predictions of observed rainfall compared to the forecast of the empirical model. In order to apply the flood forecasting methodology, we modelled the urban basin of São Carlos using SWMM model. The rainfall-runoff simulations performed with the basin model showed satisfactory adjustments compared with actual flood events. Since the use of voluntary information on flood forecasting is a fairly new concept, another important contribution of this work was the proposition of spatiotemporal parameters that influence on the forecast caused by the use of VGI data. There are many scenarios and combinations which using volunteered information can be helpful in the flood forecasting. In this work we consider only one combination. Due to absence of real volunteered data, we use sensor data to simulate VGI data. Several hypotheses have been raised to the inclusion of volunteers in HAMPB data model to produce more relevant results than using traditional methods of forecasting.

Följande studie syftar till att analysera mindre kommuners hinder och möjligheter i det kommunala klimatanpassningsarbetet. Studien belyser även hur kritiska faktorer tar sig form som betydande i klimatanpassningsarbetet enligt aktörerna. Studiens empiriska material är baserat på sex semistrukturerade intervjuer, genomförda med aktörer med varierande yrkesroll i fyra svenska kommuner. Analysen av det empiriska materialet identifierade ett antal teman som lyfte faktorer som ansågs betydelsefulla att belysa i mindre kommuners kommunala klimatanpassningsarbete. Identifierade teman var följande: ekonomiska barriärer, politik, kompetens, interna och externa samverkansprocesser och stöd och vägledning i klimatanpassningsarbetet. Studien visade att mindre kommuner har ett antal möjligheter som ansågs betydande i det kommunala klimatanpassningsarbetet och dessa bestod av korta beslutsvägar och god intern och extern kommunikation. Studien pekade på att mindre kommuners klimatanpassningsarbete karaktäriseras av fler hinder än möjligheter, något som anses hämma implementeringen i det kommunala klimatanpassningsarbetet. Hindren utgörs av bristande förståelse från allmänheten, bristande intresse på politisk nivå, svårigheter i att rekrytera relevant kompetens samt att definiera och strukturera det egna klimatanpassningsarbetet. Studien visar även att det är komplext för mindre kommuner att endast tala om översvämningar i klimatanpassningsarbetet, därav pekar studien på att mindre kommuner behöver få hjälp att skala ner riktlinjer till den egna kommunens kapacitet. Mindre kommuners långsiktiga och strategiska mål i kommunalt klimatanpassningsarbete anses vara viktiga variabler att belysa i framtida studier. / The following study aims to analyze the barriers and opportunities for less-populous municipalities in the climate adaptation work. The study also highlights critical issues taking shape as important to climate adaptation work according to the actors and how they differ in their work towards higher populated municipalities. The study's empirical material is based on six semi-structured interviews, conducted with actors with varying professional roles in four Swedish municipalities. The analysis of the empirical material identified several themes that were considered important in the municipalities' climate adaptation work. Identified themes were as follows: economic barriers, politics, competence, internal and external collaboration processes and support and guidance in climate adaptation work.The study showed that less-populous municipalities have a number of opportunities that were considered significant in the municipal climate adaptation work and these consisted of short decision paths and good internal and external communication. The study pointed out that less-populous municipalities' climate adaptation work is characterized by more obstacles than opportunities, something that is considered to impede the implementation. The obstacles consist of a lack of understanding from the public, a lack of interest at the political level, difficulties in retaining and recruiting relevant competence, and defining and structuring the local climate adaptation work. The study also shows that it is complex for less-populous municipalities to only talk about flooding in the climate adaptation work, hence the study points out that less-populous municipalities need to acquire tools to be able to scale down guidelines to their own municipality's capacity. The municipalities' long-term and strategic goals in the climate adaptation work are considered to be important variables to highlight in future studies.