This research presents methods of creating digital maps for floodplain delineation and flood probability studies and storing them in a geodatabase. Methods for creating a geodatabase for water resources outside of a GIS are presented. The geodatabase follows the ArcHydro data model. Methods are also shown for creating digital flood maps and storing them in the geodatabase. These flood maps, defining the floodplain boundary and flood probability, are stored in a digital format ready for use in a FEMA flood hazard project, allowing for better archival methods and reproducibility.

The interactions between rivers, surrounding hydrogeological features, and hydraulic structures such as bridges are not well-established or understood at the network scale, especially under transient conditions. The cascading hydraulic effects of local perturbations up- and downstream of the site of perturbation may have significant, unexpected, and far-reaching consequences, and therefore often cause concern among stakeholders. The up- and downstream hydraulic impacts of a single structural modification may extend much farther than anticipated, especially in extreme events. This work presents a framework and methodology to perform an analysis of interdependent bridge-stream interactions along a river corridor. Such analysis may help prioritize limited resources available for bridge and river rehabilitations, allow better-informed cost/benefit analysis, facilitate holistic design of bridges, and address stakeholder concerns raised in response to planned bridge and infrastructure alterations. The stretch of the Otter Creek from Rutland to Middlebury, VT, is used as a test bed for this analysis. A two-dimensional hydraulic model is used to examine the effects individual structures have on the bridge-stream network, particularly during extreme flood events. Results show that, depending on their characteristics, bridges and roadways may either attenuate or amplify peak flood flows up- and downstream, or have little to no impact at all. Likewise, bridges may or may not be sensitive to any changes in discharge that result from perturbation of existing structures elsewhere within the network. Alterations to structures that induce substantial backwaters may result in the most dramatic impacts to the network, which can be either positive or negative. Structures that do not experience relief (e.g., roadway overtopping) may be most sensitive to network perturbations.

I Sverige finns idag en vedertagen metod för att bestämma dimensionerande flöde för dammanläggningar. De teoretiska beräkningarna av dimensionerande flöde för dammanläggningar tillhörande flödesdimensioneringsklass I baseras på HBV-modellen, en begreppsmässig hydrologisk beräkningsmodell som beskriver samspelet mellan de meteorologiska och hydrologiska förhållanden som råder inom ett avrinningsområde. Begreppsmässiga hydrologiska modeller baseras på vattenbalansen och används för att bestämma tillrinning till vattendrag, sjöar eller andra vattenförekomster. Vid hydrologisk modellering med begreppsmässiga modeller tas ingen explicit hänsyn till vattendragets geometri. Trånga sektioner i naturliga vattendrag kan hindra vattnets framfart och orsaka dämning uppströms den trånga sektionen. Till följd av det kan en del av flödestoppen kvarhållas i terrängen och därmed dämpas och fördröjas. Hydrauliska modeller beskriver vattnets flöde genom vattendraget. Högupplöst höjddata utgör grunden i en hydraulisk modell och vid hydraulisk modellering tas således hänsyn till avrinningsområdets topografi såväl som vattendragets batymetri. Syftet med detta examensarbete var att analysera tillförlitligheten i beräknade dimensionerande flöden framtagna enligt Flödeskommitténs Riktlinjer för bestämning av dimensionerande flöden för dammanläggningar. Genom att upprätta hydrauliska modeller över två specifika vattendragssträckor som berörs av trånga sektioner kunde det undersökas huruvida de trånga sektionerna orsakar någon flödesdämpning samt om flödesdämpningen beror av storleken på vattenflödet. De områden som var föremål för denna studie var en delsträcka av Övre Lagan samt en del av Bolmån som är Lagans största tillflöde. Resultaten visade att flödestopparna dämpades och att det var de trånga sektionerna som orsakade den huvudsakliga flödesdämpningen. Vidare visade resultaten att den relativa dämpningen beror av storleken på inflödet i de hydrauliska modellerna. Den relativa dämpningen av det dimensionerandet flödet vid Övre Lagan var marginell, 1,2 % respektive 2,0 %, medan den vid Bolmån uppgick till 6,7 %. Det faktum att de dimensionerande flödena emellertid dämpades i de båda fallen bör vara skäl nog att se över metoden för bestämmandet av dimensionerande flöden för dammanläggningar tillhörande flödesdimensioneringsklass I och undersöka huruvida det är möjligt att innefatta hydraulisk modellering i den idag vedertagna beräkningsmetodiken. / In Sweden there is currently an accepted method for determining the design floods for dams which is described in The Swedish Design Flood Guidelines. The theoretical calculations of the design floods for dams associated with Flood Design Category I are based on the HBV model, a conceptual hydrological model that describes the interaction between the meteorological and hydrological conditions within a basin. Conceptual hydrological models are based on the water balance and are used to determine runoff to streams, lakes or other bodies of water. Conceptual hydrological models do not take explicit account for the geometry of the watercourse. Narrow sections in natural streams may prevent water flow and cause impoundment upstream from the narrow section. Following that, a part of the flow peak can be retained in the terrain and thereby attenuated and delayed. Hydraulic models describe the flow of water through the watercourse. High resolution elevation data is the foundation of a hydraulic model and hydraulic models thus take into account the basin topography as well as the watercourse bathymetry. The objective of this study was to analyze the reliability of design floods that have been determined according to The Swedish Design Flood Guidelines. By establishing hydraulic models of two specific streams affected by narrow sections it could be examined whether the narrow sections cause flow attenuation and whether the flow attenuation depends on the size of the water flow. The areas which were the subject of this study were a subsection of River Lagan and part of River Bolmån, which is River Lagan’s largest tributary. The results of the hydraulic model simulations showed that the flow peaks were attenuated and that it was the narrow sections that caused the main flow attenuation. Furthermore, the results showed that the relative attenuation depends on the size of the inflow in the hydraulic models. The relative attenuation of the design floods was 1.2 % and 2.0 % at River Lagan and 6.7 % at River Bolmån. The relative attenuation of the design flood was thus marginal at River Lagan. The fact that the design floods nevertheless were attenuated at both areas which were the subject of this study should be reason enough to review the method for the determination of design floods for dams associated with Flood Design Category I and examine whether it is possible to include hydraulic modeling in today’s conventional calculation methodology.

Ett allt vanligare uppdrag inom hydraulisk modellering är att undersöka hur nya bostads- och handelsområden påverkar statusen för äldre befintliga ledningsnät. I nya områden anläggs nästan uteslutande separatsystem och eftersom nya områden oftast uppförs utanför den befintliga bebyggelsen måste spillvattnet från dessa områden transporteras genom det befintliga avloppsnätet, vilket kan vara helt eller delvis kombinerat. I stadsdelen Hjorthagen i Stockholm planeras 5000 nya lägenheter att byggas och spillvattenflödet från dessa skall anslutas uppströms det befintliga kombinerade ledningsnätet i området. Examensarbetet har gått ut på att undersöka hur det kombinerade ledningssystemet påverkas av den tillkommande spillvattenbelastningen. Syftet var att undersöka hur den dimensionerande spillvattenavrinningen påverkar de åtgärder och kostnader som behövs för att få det utökade ledningsnätet att fungera, samt att utreda behovet av ytterligare anpassningar av ledningsnätet inför framtida klimatförändringar. Vid beräkning av bräddvolymer simuleras vanligen spillvattenavrinningen från medeldygnsförbrukning av vatten. I studien har det även ingått att undersöka om detta sätt ger lägre bräddvolymer jämfört med att variera vattenförbrukningen med ett veckomönster. Med modelleringsprogrammet MIKE Urban undersöktes tre fall av dimensionerande spillvattenflöde från det tillkommande området i Hjorthagen. Olika stor säkerhetsmarginal användes vid dimensioneringen. I alla tre fallen fick det tillkommande spillvattenflödet kapaciteten i det kombinerade ledningssystemet att överskridas redan vid torrväder, med bräddning som följd. Undersökningen visade att ju högre säkerhetsmarginal dimensioneringen innebar desto mer omfattande blev de åtgärder som krävdes för att få bräddningen att upphöra. Fallet med störst säkerhetsmarginal krävde ett utjämningsmagasin på 142 m3 och att dimensionen på 670 m ledning ökades från 400 mm till 600 mm med en uppskattad åtgärdskostnad på omkring nio miljoner kronor. De åtgärder som krävdes för att undvika bräddning vid torrväder var i alla tre fallen tillräckliga för att både minska bräddningen vid regnväder och för att klimatanpassa ledningsnätet. I de fall som undersöktes kunde ingen trend ses som visade att simulering av dag- och spillvattenavrinning, utan veckovariationer i vattenförbrukningen, skulle ge för låga bräddvolymer. / An increasingly common assignment in hydraulic modeling is to investigate how sewage from new residential and commercial areas affect the status of existing sewer systems. In new areas the sewer systems are constructed to operate separately from storm drains and since new areas often are founded in the outskirt of existing areas the sanitary sewage from these areas must be transported through the older existing sewer system, which can be completely or partly combined. In the district of Hjorthagen in Stockholm 5,000 new apartments are planned to be built and sewage from these must be connected upstream of existing combined sewer system in the area. The purpose of this master thesis was to investigate how combined sewer system is affected by additional sewage load. The aim was to investigate how the choice of design sewage flow affects the measures and costs necessary to get the extended sewer system to function, and to consider the need for further adjustments to future climate change. When calculating volumes of combined sewer overflow the sewage flow usually is simulated as discharge from average water use. One objective with this thesis was to investigate whether this method gave lower volumes of combined sewer overflow as compared to using a weekly pattern. By using the modeling program MIKE Urban three choices of design sewage flow, from the new area in Hjorthagen, were investigated. The margin of safety when designing the sewage flow was increased in each case. The results showed that the capacity of the combined sewer system was exceeded during dry weather, with overflow as a result. The investigation showed that the higher margin of safety used the more extensive measures was needed. The greatest margin of safety required a storage basin of 142 m3 and that the dimension of 670 m of pipes was increased. To stop the overflow at dry weather the measures required in each case were sufficient to both reduce overflow during wet weather and to adjust the sewer system to future climate. Simulating the rainfall runoff and sewage flow, without weekly variations in water consumption did not underestimate the volumes of combined sewer overflow compared to varying the water use.

This dissertation describes three aspects of the comprehensive rotorcraft analysis. First, a physics-based methodology for the modeling of hydraulic devices within multibody-based comprehensive models of rotorcraft systems is developed. This newly proposed approach can predict the fully nonlinear behavior of hydraulic devices, and pressure levels in the hydraulic chambers are coupled with the dynamic response of the system. The proposed model evaluates relevant hydraulic quantities such as chamber pressures, orifice flow rates, and pressure relief valve displacements. This model could be used to design lead-lag dampers with desirable force and damping characteristics. The second part of this research is in the area of computational aeroelasticity, in which an interface between computational fluid dynamics (CFD) and computational structural dynamics (CSD) is established. This interface enables data exchange between CFD and CSD with the goal of achieving accurate airloads predictions. In this work, a loose coupling approach based on the delta-airload method is developed in a finite-element method based multibody dynamics formulation, DYMORE. A loose coupling analysis between a CFD code, OVERFLOW-2, and a CSD program, DYMORE, is performed to validate this aerodynamic interface. The ability to accurately capture the wake structure around a helicopter rotor is crucial for rotorcraft performance analysis. In the third part of this thesis, a new representation of the wake vortex structure based on Non-Uniform Rational B-Spline (NURBS) curves and surfaces is proposed to develop an efficient model for prescribed and free wakes. The proposed formulation has the potential to reduce the computational cost associated with the use of the Helmholtz¡¯s law and the Biot-Savart law when calculating the induced flow field around the rotor. An efficient free wake analysis will considerably decrease the computational cost of comprehensive rotorcraft analysis, making the approach more attractive to routine use in industrial settings.

This study deals with the investigation of characteristics of a flash flood and development of design of flood mitigation facilities occurred in G&uuml / zelyurt in North Cyprus on 18th of January, 2010 and development of design of flood mitigation facilities. Hydrologic and hydraulic modeling of this flood event has been utilized to develop solutions for preventing the region from the flood. Topographical maps and soil properties are used in hydrological modeling. The data are inserted into a geographical information system program (ARC-GIS) where basin properties are obtained. Since there is no any stream flow gauging station along the creeks in the study area, the synthetic unit hydrograph is developed by using Soil Conversation Service Method to obtain design flood hydrographs. In hydraulic modeling, the cross-section data of Fabrika Creek and Bostanci Creek are taken by using global navigation satellite system (GNSS) device and total station. These data are entered into the HEC-RAS program. Flood inundation maps are generated for both creeks. After hydrological and hydraulic modeling, two solutions are proposed. The first one is to build a detention basin for storing water and a lateral channel. for diverting extra flow from Bostanci Creek to Fabrika Creek. The second solution is to build a lateral channel from Bostanci Creek to G&uuml / zelyurt Dam for diverting all water during a flood event. Based on hydrologic, hydraulic, and cost analysis, the first solution is accepted to be the feasible solution. In addition, flow carrying capacities of the creeks are improved.

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Foi desenvolvido um modelo hidrÃulico, implementado na linguagem de programaÃÃo Delphi, para simulaÃÃo de redes de abastecimento de Ãgua, que utiliza o MÃtodo das CaracterÃsticas (MOC), introduzindo novas capacidades ao modelo CALHIDREDMT de Righetto (1994). O modelo se baseia no conceito de pseudo-transiente, utilizando um valor fictÃcio para a celeridade da onda no MOC. Foram realizadas simulaÃÃes em redes equipadas com reservatÃrios de nÃvel fixo e variÃvel (tanques), estaÃÃes elevatÃrias e boosters, considerando situaÃÃes estÃticas e de perÃodo estendido (24 horas), para casos reais e exemplos genÃricos de redes. Os resultados do modelo desenvolvido foram comparados Ãs simulaÃÃes realizadas no modelo EPANET e com dados de pressÃo medidos em manÃmetro instalado para experimento de campo. Foram avaliados aspectos de convergÃncia do MOC nos elementos de fronteira e o desempenho dessa tÃcnica de soluÃÃo para diferentes configuraÃÃes de rede. AlÃm disso, o modelo hidrÃulico foi acoplado a uma rotina de otimizaÃÃo baseada em Algoritmos GenÃticos (AG). A rotina de otimizaÃÃo apresenta uma funÃÃo objetivo formulada para minimizaÃÃo dos custos energÃticos nas estaÃÃes elevatÃrias, considerando a penalizaÃÃo de aspectos indesejados da operaÃÃo, como pressÃes e velocidades elevadas, excesso de manobras nas bombas e violaÃÃo de limites em tanques. Foram realizadas anÃlises quanto Ãs formas de tarifaÃÃo e variaÃÃo dos parÃmetros do AG, avaliando a influÃncia desses aspectos sobre o valor da funÃÃo objetivo e o tempo de processamento. Foi possÃvel concluir que o modelo apresenta desempenho satisfatÃrio e bastante flexibilidade, tendo potencial para aplicaÃÃes em operaÃÃo de redes pressurizadas de distribuiÃÃo em tempo real. / A hydraulic model was developed for simulation of water supply networks using the Method of Characteristics (MOC), introducing new features to the CALHIDREDMT model, proposed by Righetto (1994). The model uses the concept of pseudo-transient, using a fictitious value for the wave celerity. Simulations were performed in networks equipped with reservoirs, tanks, pump stations and boosters, considering both steady-state situations, as well as extended-periods (24 hours), including real cases and generic examples. The obtained results were compared to simulations performed in the model EPANET and to field experiments (pressure data measured with a manometer). Convergence issues and the performance of the solution technique were analyzed in the boundary elements for different network configurations. In addition, the hydraulic model was coupled into a Genetic Algorithms (GA) routine. The Genetic Algorithm routine presents an objective function that considers the minimization of the energetic costs associated with pump stations and it includes ways to penalize undesired issues in the operation, like high values of pressure and velocity, surplus of pump station maneuvers and violation of tank capacity limits. Analyses were performed considering variations in the taxation formulas, penalization criterions and GA parameters to evaluate the influence of these issues in the objective function and the routine processing time. The model presented a satisfactory performance and flexibility. It can be used as an analytical tool for applications involving water distribution networks in real time.

Expansion of cities and major infrastructure projects lead to changes in land use and river flows. The probability of flooding is expected to increase in the future as a result of these changes in combination with climate change. Hydraulic models can be used to obtain simulated water levels to investigate the risk of flooding and identify areas that might potentially be flooded due to climate change. Since a model is a simplification of the reality it is important to be aware of a model’s uncertainties. A part of this study is therefore aimed to perform a sensitivity analysis to determine which parameter has the largest impact on the model result and has to be treated more careful and accurately. In this study the 1-dimensional flow model Hydrologic Engineering Center-River Analysis System (HEC-RAS) were assed to simulate predicted water levels within the studied river. Topographic data was used to draw cross sections in Geographic Information Systems (GIS) with additional tools of HEC-GeoRAS, in order to get information about the streams geometry. The purpose of doing a sensitivity analysis was attained by investigating changes of the model results when changing different input parameters. This work is based on a reach along Mora river, in Södertälje, Sweden, as a case study. The sensitivity analysis indicate that the number of cross sections has a significant effect when simulating water levels of low flows and that the absolute error of simulated water levels increases as the average spacing between cross sections increases. The second part of the study aims to examine the effects of climate change and how it will affect water levels for the studied river. The results of the study showed that simulated water levels with flows of 100, 200 and 500 years return periods stay within the river channel and do not indicate flooded areas. The results also showed that a backwater effect due to sea level rise would affect the water levels in the stream up to a specific critical point along the studied reach. The lower reach indicated results to contain more uncertain region, where floodplain delineation changed easily as the number of cross section was changed. It is therefore important to identify the areas where uncertainties can be more critical for the results. Because of the uncertainties associated to the model used, it is important to notice that the results of this work correspond particularly to the case study in Mora River. / Studien genomförs inom Ostlänken, som är den första delsträckan av en ny höghastighetsjärnväg mellan Järna och Linköping. Bebyggelse och stora infrastrukturprojekt kommer förändra markanvändning och flöden i vattendrag. I följd av dessa förändringar, tillsammans med framtidens förändrade klimat, kommer risken för översvämningar kunna öka. För att undersöka riskerna för översvämningar och kartlägga områden som riskerar att översvämmas är en hydraulisk modell ett verktyg som kan användas. Då en modell endast är en förenkling av verkligheten och påverkas av flera olika parametrar är det viktigt att vara medveten om modellers osäkerheter. För att få modellen att efterlikna verkligheten så bra som möjligt kan det vara bra att veta vilka parametrar som har störst inverkan på modellens resultat och som bör bearbetas mer noggrant. Därmed är en del av studiens syfte att göra en känslighetsanalys för att utreda vilka modellparametrar och indata som påverkar modellresultaten, med fokus på att analysera simulerade vattennivåer. Känslighetsanalysen utförs genom en fallstudie över Moraån, där den endimensionella flödesmodellen HEC-RAS används för att beräkna vattendragets vattennivåer. Den andra delen av studiens syfte är att undersöka om hur framtidens klimatförändringar kommer kunna påverka det studerade området. En effekt av framtidens förändrade klimat är stigande havsnivåer som leder till ökad risk för översvämning vid kustnära områden. Till följd av dämningseffekter kommer de stigande havsnivåerna även ge ökade vattennivåer uppströms vattendragen, och beroende på vattendragens egenskaper och geometri kommer vattendrag längs med kusten att påverkas på olika sätt. För att undersöka riskerna för översvämningar i ett framtida klimat har modeller med olika klimatscenarios byggts upp där stigande havsnivåer kombinerats med flöden av varierande återkomsttider.

The aim of the diploma thesis is to asses the current state of a selected part of the sewer network in Znojmo, design of possible remediation and theoretical design of retention tank. The work is devided into an accompanying report, technical report, hydraulics and drawing documentation. The assesment consist of the determination structural and technical condition of selected parts of the sewer network with a proposal for remediation and economic evaluation. The hydraulic part describes the hydraulic model in program SWMM, there are processed here hydraulic calculation and there are 4 different variants of the design of retention tanks.

No description available.