The optimal use of resources in a floodplain is important especially as marginal returns increase in value. Flood control measures which protect floodplain development need to be conservative to allow for future growth. This thesis presents a methodology whereby the likelihood of flooding of a river is determined from Monte Carlo simulations using a numerical river model. The river model is based on the hydrodynamic equations of motion and continuity while the stochastic parameters of the river are determined from recorded discharge data from the Nicomekl River, Surrey B.C., which is used as the test case of this study. Comparisons are made between simulated and recorded data with predictions of flood probabilities and conclusions as to the use of the methodology. / Applied Science, Faculty of / Civil Engineering, Department of / Graduate

Une inondation est un aléa hydro climatique naturel qui ne devient un risque que lorsqu’elle représente une menace pour les enjeux humains et matériels. Ce phénomène naturel mobilise autant qu’il divise. Datant de l’Antiquité, il s’agit pourtant d’un sujet brûlant d’actualité. Si les pertes humaines sont moins nombreuses, le coût des catastrophes s’alourdit en raison de l’anthropisation des zones littorales. Faute de pouvoir dompter la nature, il s’agit de la réguler,en conciliant des intérêts antagonistes. L’objectif fixé par la directive inondation du 23 octobre 2007, est d’en réduire les conséquences dommageables, sur le plan humain,économique et environnemental. Le risque est un paradigme qui a évolué d’une vision aléa centrée, top down, à une analyse bottom up des vulnérabilités. Quelle est la place du droit dans l’appréhension du risque inondation ? Ce sujet se situe au carrefour de plusieurs branches du droit et de sciences non juridiques. Il s’exprime sous trois dimensions : la connaissance issue des sciences dures ; les représentations cognitives sociétales et les décisions juridico-politiques et économiques. Cette imbrication révèle que le droit positif doit faire preuve d’humilité et de lucidité en admettant qu’il n’est pas omnipotent et qu’il ne peut réguler seul, les problématiques du risque inondation. Les changements climatiques augurent une aggravation de l’intensité et de l’occurrence des phénomènes catastrophiques. Comment les politiques publiques et la recherche académique se préparent-elles à répondre à des phénomènes inédits ? Comment parvenir au courage politique d’une refonte de la solidarité assurantielle, afin de faire face à l’accroissement du quantum des indemnisations ? Quid de la transition énergétique qui constitue une réponse holistique et intégrée, à la gestion du risque inondation ? Comment assurer le recul stratégique des habitations et des activités menacées ou rognées par les submersions permanentes et l’érosion côtière ? Le droit interne est pléthorique et souffre d’un manque de lisibilité des politiques publiques, malgré des réformes de la gouvernance. Inversement, le droit international déplore un no man’s land juridique sur l’absence de statut de migrant environnemental ? Quelles seront les conséquences juridiques et géostratégiques de l’inhumation marine d’Etats insulaires ou de l’atrophie des frontières territoriales ? Le droit souple apporte des éléments de réponse, qui permettraient de sortir de l’impasse souverainiste ou des accords incantatoires. Enfin, quel est le rôle de la jurisprudence dans cette régulation ? L’office des juges est pluraliste. Chacun, dans sa plénitude de juridiction, assure une fonction préventive, réparatrice ou punitive, du risque inondation. / Flood risk is the most important natural risk in France. This phenomenon is not new, but its occurrence and its consequences are likely to worsen due to climate change and the anthropization of littoral and river areas. Given the economic, environmental and political stakes, positive law must understand this natural risk and even anticipate new phenomena that will have a major impact on our societies. This involves critically analyzing the regulation of flood risk by dissociating institutional regulation from judicial regulation. The state of positive law is endowed with an almost indigestible normative framework. The objective is to clarify integrated public policies, to improve the access of citizens to federate towards a genuine risk culture.

Several previous studies have compared design storms with continuous simulation results for the purposes of estimating flood frequency distributions. These previous studies were limited in scope to primarily urban single lumped catchments. This thesis attempted to perform a more detailed comparison of design storm and continuous simulation flood frequency distributions by extending the analysis to different basin types, as well as examining the effect of more complex watershed systems and storage elements (detention ponds). It was found that design storms could reasonably reproduce continuous simulation flood frequency distributions if an appropriate distribution and antecedent conditions were selected. Design storms were found to compare increasingly well to continuous simulation results in more complex watershed systems and through storage elements. / Thesis / Master of Applied Science (MASc)

<p>The old water system in Sala, formerly belonging to thesilver mine, is analysed with regard to dam safety focusing onthe hydrological aspects. The hydrological safety of the riskclass I dams in the area, built in the 16th century, is notconsidered adequate according to the Swedish guidelines fordesign flood determination. A review is made of internationalprinciples for design flood determination. The overview showsthat there is no common principle used internationally whendealing with design flood for dams. In some countries there isan ambition to implement risk assessment for evaluation ofhydrological safety. However, at present Australia is the onlycountry that has fully integrated risk assessment in theirdesign flood guidelines. A risk assessment of the water systemin Sala shows that neither increasing the spillway capacity norimplementing flood mitigation measures in the watershed haveany significant effect on dam safety in the area. Nothingindicates that watersheds with a high presence of mires, likein the Sala case, should be particularly well suited forimplementing flood mitigation in the watershed as a dam safetymeasure. In order to safely handle the design flood in Sala andavoid dam failure due to overtopping the flood needs to bediverted from the water system.</p><p><b>Key words:</b>dam safety; design flood; flood mitigation;hydrological; risk assessment</p>

A linear reservoir cell model is presented which is proposed as a good candidate for real time flood forecasting applications. The model is designed to be computationally efficient since it should be able to run on a P.C and must operate online in real time. The model parameters and forecasts can be easily updated in order to allow for a more accurate forecast based on real time observations of streamflow and rainfall. The final model, once calibrated, should be able to operate effectively without requiring highly skilled and knowledgeable operators. Thus it is hoped to provide a tool which can be incorporated into an early warning system for mitigation of flood damage, giving water resources managers the extra lead-time to implement any contingency plans which may be neccssary to ensure the safety of people and prevent damage to property. The use of linear models for describing hydrological systems is not new, however the model presented in this thesis departs from previous implementations. A particular departure is the novel method used in the conversion of observed to effective rainlfall. The physical processes that result in the rainfall to runoff conversion are non-linear in nature. Most of the significant non-linearity results from rainfall losses, which occur largely due to evaporation and human extraction. The remaining rainfall is converted to runoff. These losses are particularly significant in the South African climate and in some regions may be as much as 70-90 % of the total observed rainfall. Loss parameters are an integral part of the model formulation and allow for losses to be dealt with directly. Thus, input to the model is observed rainfall and not the "effective" rainfall normally associated with conceptual catchment models. The model is formulated in Finite Difference form similar to an Auto Regressive Moving Average (ARMA) model; it is this formulation which provides the required computational efficiency. The ARMA equation is a discretely coincident form of the State-Space equations that govern the response of an arrangement of linear reservoirs. This results in a functional relationship between the reservoir response constants and the ARMA coefficients, which guarantees stationarity of the ARMA model. / Thesis (M.Sc.Eng.)-University of Natal, Durban, 2001.

In recent years, there have been significant researches on holistic approaches to design flood estimation in Australia. The Monte Carlo Simulation technique, an approximate form of Joint Probability Approach, has been developed and tested to small gauged catchments. This thesis presents the extension of the Monte Carlo Simulation Technique to large catchments using runoff routing model URBS. The URBS-Monte Carlo Technique(UMCT),has been applied to the Johnstone River and Upper Mary River catchments in Queensland. The thesis shows that the UMCT can be applied to large catchments and be readily used by hydrologists and floodplain managers. Further the proposed technique provides deeper insight into the hydrologic behaviour of large catchments and allows assessment of the effects of errors in inputs variables on design flood estimates. The research also highlights the problems and potentials of the UMCT for application in practical situations. / Masters of Engineering (Hons.)

Design flood estimation is often required in hydrologic practice. For catchments with sufficient streamflow data, design floods can be obtained using flood frequency analysis. For catchments with no or little streamflow data (ungauged catchments), design flood estimation is a difficult task. The currently recommended method in Australia for design flood estimation in ungauged catchments is known as the Probabilistic Rational Method. There are alternatives to this method such as Quantile Regression Technique or Index Flood Method. All these methods give the flood peak estimate but the full streamflow hydrograph is required for many applications. The currently recommended rainfall based flood estimation method in Australia that can estimate full streamflow hydrograph is known as the Design Event Approach. This considers the probabilistic nature of rainfall depth but ignores the probabilistic behavior of other flood producing variables such as rainfall temporal pattern and initial loss, and thus this is likely to produce probability bias in final flood estimates. Joint Probability Approach is a superior method of design flood estimation which considers the probabilistic nature of the input variables (such as rainfall temporal pattern and initial loss) in the rainfall-runoff modelling. Rahman et al. (2002) developed a simple Monte Carlo Simulation technique based on the principles of joint probability, which is applicable to gauged catchments. This thesis extends the Monte Carlo Simulation technique to ungauged catchments. The Joint Probability Approach/ Monte Carlo Simulation Technique requires identification of the distributions of the input variables to the rainfall-runoff model e.g. rainfall duration, rainfall intensity, rainfall temporal pattern, and initial loss. For gauged catchments, these probability distributions are identified from observed rainfall and/or streamflow data. For application of the Joint Probability Approach to ungauged catchments, the distributions of the input variables need to be regionalised. This thesis, in particular, investigates the regionalisation of the distribution of rainfall duration and intensity. In this thesis, it is hypothesised that the distribution of storm duration can be described by Exponential distribution. The developed new technique of design flood estimation can provide the full hydrograph rather than only peak value as with the Probabilistic Rational Method and Quantile Regression Technique. The developed new technique can further be improved by addition of new and improved regional estimation equations for the initial loss, continuing loss and storage delay parameter (k) as and when these are available. / (M. Eng.) (Hons)

With the depletion of the existing reservoirs and the decline in oil discoveries during the last few decades, enhanced oil recovery (EOR) methods have gained a lot of attention. Among the various improved recovery methods, waterflooding is by far the most widely used. However, the presence of reservoir heterogeneity such as high permeability streaks often leads to premature breakthrough and poor sweep resulting in reduced oil recovery. This underscores the need for a prudent reservoir management, in terms of optimal production and injection rates, to maximize recovery. The increasing deployment of smart well completions and i-field has inspired many researchers to develop algorithms to optimize the production/injection rates along intervals of smart wells. However, the application of rate control for other EOR methods has been relatively few. This research aims to extend previous streamline-based rate optimization workflow to polymer flooding and CO2 flooding. The objective of the approach is to maximize sweep efficiency and minimize recycling of injected fluid (polymer/CO2) by delaying its breakthrough. This is achieved by equalizing the front arrival time at the producers using streamline time-of-flight. Arrival time is rescaled to allow for optimization after breakthrough of injected fluid. Additionally, we propose an accelerated production strategy to increase NPV over sweep efficiency maximization case. The optimization is performed under operational and facility constraints using a sequential quadratic programming approach. The geological uncertainty has been accounted via a stochastic optimization framework based on the combination of the expected value and variance of a performance measure from multiple realizations. Synthetic and field examples are used extensively to demonstrate the practical feasibility and robustness of our approach for application to EOR processes.

Thesis (M. Env. St.)--University of Adelaide, Mawson Graduate Centre for Environmental Studies, 1994? / Includes bibliographical references (leaves 83-86).

Thesis (Ph.D.)--University of Adelaide, Dept. of Civil and Environmental Engineering, 2002. / "May 2002" Includes list of papers published during this study. Errata slip inserted inside back cover of v. 1. Includes bibliographical references (leaves 331-357).