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The thesis address the field of stormwater management. With a changing climate, the field of stormwater management much like many other fields will need to incorporate sustainable development if overall sustainability is to be reached. The aim of the thesis is to evaluate the current method for dealing with stormwater in Sweden, mainly in urban areas, and point to issues at hand and identified ways of addressing them. The concept of Rainwater Harvesting (RWH) is assessed. A comparison of results from several case studies from around the world show that there are several aspects of high importance for the viability of such technology. Among others price for municipal water, ability to lower costs due to smart planning ahead of installing, inclusion of environmental aspects and impacts on society such as reduced load on water, wastewater and stormwater infrastructure, reduced pollution load and greenhouse gas emissions (mainly due to less water treated at wastewater treatment facilities). The main conclusion from comparing and compiling results were that the viability of RWH from an economic standpoint is questionable. Although if including all identified gains for the municipality including stormwater management benefits and indirect gains due to reduced load and taking all aspects of importance into consideration there is potential for such technology even in a country like Sweden with good water supply and infrastructure in place. This thesis is of importance since it brings RWH technology into the light as a potential sustainability measure in Sweden. It evaluates the important parameters for the technology to be viable as indicated by case studies and literature within the field. / Detta examensarbete behandlar hållbar dagvattenhantering och specifikt tekniken Rainwater harvesting. Nuvarande centrala system för att förse Stockholm med färskvatten samt hantera bildat dagvatten utvärderas i en litteraturstudie. Även identifierade metoder för att hantera dagvattnet i linje med hållbarhetsmål beskrivs. Tekniken Rainwater harvesting beskrivs, dess historia samt implementering i moderna sammanhang framställs. Flertalet fallstudier där tekniken beskrivs analyseras och jämförs. Detta examensarbete är av vikt eftersom det tar upp tekniken RWH i relation till Sverige som potentiellt lokalt system för att uppnå hållbarhet. Det utvärderar viktiga parametrar för att tekniken ska anses försvarbar vilka indikeras av flertalet fallstudier samt litteratur. Dagens system för hantering av dagvatten i Stockholm består till allra största grad av det centrala avloppssystemet bestående av kombinerat samt duplikat avloppsnät. Detta har likt många centrala infrastruktursystem nackdelen att det är kostsamt och besvärligt att uppdatera och stärka, men dessutom flertalet nackdelar relaterade till miljöpåverkan och hög belastning på reningsverk. Rainwater harvesting är en teknik med lång historia som i moderna samhällen implementeras i syfte att minska vattenanvändningen samt belastningen på centralt dagvattensystem. Blandade ekonomiska resultat har observerats, sannolikt på grund av varierande analysmetoder och varierande inkludering av viktiga parametrar i bedömningar. Miljönyttan är till viss del tydlig, dock i många fall ej medtagen i beräkningar och utvärderingar. Analys av fallstudier påvisar hög potential för tekniken vid smart implementering men att det även finns goda exempel på system som resulterat i mycket dåliga ekonomiska resultat. Flertalet viktiga aspekter att ta hänsyn till för att uppnå försvarbara resultat har identifierats och beskrivits. Huvudslutsatsen är att Rainwater harvesting i och med sin potential att nå eller jobba mot definierade mål för dagvattenhantering och hållbar utveckling bör has med i åtanke som potentiellt lokalt system i Sverige kommande år.

Public water supplies contain disease-causing microorganisms in the water or distribution ducts. In order to kill off these pathogens, a disinfectant, such as chlorine, is added to the water. Chlorine is the most widely used disinfectant in all U.S. water treatment facilities. Chlorine is known to be one of the most powerful disinfectants to restrict harmful pathogens from reaching the consumer. In the interest of obtaining a better understanding of what variables affect the levels of chlorine in the water, this thesis will analyze a particular set of water samples randomly collected from locations in Orange County, Florida. Thirty water samples will be collected and have their chlorine level, temperature, and pH recorded. A linear regression analysis will be performed on the data collected with several qualitative and quantitative variables. Water storage time, temperature, time of day, location, pH, and dissolved oxygen level will be the independent variables collected from each water sample. All data collected will be analyzed through various Statistical Analysis System (SAS®) procedures. Partial residual plots will be used to determine possible relationships between the chlorine level and the independent variables and stepwise selection to eliminate possible insignificant predictors. From there, several possible models for the data will be selected. F tests will be conducted to determine which of the models appears to be the most useful. All tests will include hypotheses, test statistics, p values, and conclusions. There will also be an analysis of the residual plot, jackknife residuals, leverage values, Cook’s D, press statistic, and normal probability plot of the residuals. Possible outliers will be investigated and the critical values for flagged observations will be stated along with what problems the flagged values indicate.

No / `In this creative study Anand applies environmental economic tools and concepts to analyze water issues in developing countries... The author carefully integrates the poverty, inequality, and development issues of water; and he meticulously discusses the intertwined rivalrous and excludable public good characteristics of water supply... Contents: Preface 1. Introduction 2. Investigating Water 'Scarcity' 3. Access to Water Supply: Achieving the Millennium Development Goal 4. Sharing Water Peacefully: Understanding Transboundary Water-Resource Conflicts 5. An Analysis of a River Dispute: Interaction of Politics and Economics 6. Improving Access to Water: Institutions, Entitlements and Inequality 7. Consumer Preferences and Public Policy 8. Justice, Rights and Sustainability: Access to Water and the Capability Approach 9. Conclusions and a Research Agenda Bibliography Index.

In two-dimensional flow, the point of flow separation from the surface coincides with the point at which the skin friction vanishes. However, in three-dimensional flow, the situation is much more complex and the flow separation is rarely associated with the vanishing of the wall shear stress except in a few special cases. Though the effects of cross-plane separation are substantial and have been recognized for some time, the phenomenon of flow separation over three-dimensional bodies is still far from being completely understood. The flow is so complex that no completely satisfactory analytical tools are available at the moment. In an attempt to logically identify the various effects and parametric dependence while simultaneously minimizing configuration dependent issue, the flow over a 6 to 1 prolate spheroid, which is a generic three-dimensional body, is investigated. For the identification of the general flow pattern and better understanding of the flow field, surface-oil-flow visualization tests and force and moment tests were performed. The angle of attack effect and Reynolds number effect on the separation location are studied with natural transition. Forces and moments tests, surface pressure distribution measurements as well as the surface pressure fluctuations, and mini-tuft flow visualization tests were made to document the flow characteristics on the surface of the body with an artificial boundary layer trip. / Ph. D.

An examination was conducted of alternative responses to the water supply situation in four cities in southeastern Virginia. Cost/benefit analyses were performed for the provision of projected levels of use and for reductions in those levels of use achieved with the use of quotas, price increases, and water saving devices. An important element of these analyses was the consideration of the costs incurred as a result of waste water treatment with different levels of water use. The levels of the principal types of water use were estimated for each city. This provided a basis for the projection of water demand curves necessary for estimating the value of water. Optimal schedules for the development of additional water sources were derived through the examination of water demand, relative to the costs of operating and expanding water supply and waste water. treatment facilities. / Ph. D.

The reliability of future water supplies comes into question with the onset of global climate change and the variations in local weather patterns that it brings. Changes in temperature, precipitation, soil moisture, and sea level can all have an impact on drinking water storage and supply. As these impacts are realized, it is increasingly important to use forward projecting estimates of future supply through the use of general circulation models (GCMs). GCMs can be used to predict changes in local weather over the next century. Using GCM data as input to a hydrologic model of local water supplies, water supply managers can assess and be better prepared for the impact of these possible changes. Land use/demand in particular has an impact on runoff characteristics within a watershed. By incorporating changes in land use/demand into hydrologic model simulations, a more complete picture can be generated of the possible runoff characteristics, and thereby source water supply. The four land use scenarios used in this study are: 1) present day land use/demand; 2) projected land use/demand to 2040; 3) projected land use/demand to 2070; and 4) projected land use/demand to 2100. This study uses established techniques to incorporate both climate and land use/demand change into a hydrologic model of the Occoquan watershed, which encompasses an area of approximately 1,550 square kilometers in Northern Virginia, U.S.A., and is part of the drinking water supply to approximately 1.7 million residents. / Master of Science

This dissertation explores the impact of climate change and extreme weather events on critical infrastructures as defined by US Department of Homeland Security. The focus is on two important critical infrastructure systems – Water and Transportation. Critical infrastructures are always under the risk of threats such as terrorist attacks, natural disasters, faulty management practices, regulatory policies, and defective technologies and system designs. Measuring the performance and risks of critical infrastructures is complex due to its network, geographic and dynamic characteristics and multiplicity of stakeholders associated with them. Critical infrastructure systems in crowded urban and suburban areas like the Washington Metropolitan Area (WMA) are subject to increased risk from geographic proximity. Moreover, climate is challenging the assumption of stationary (the idea that natural systems fluctuate within an unchanging envelope of variability) that is the foundation of water resource engineering and planning. Within this context, this research uses concepts of systems engineering such as 'systems thinking' and 'system dynamics' to understand, analyze, model, simulate, and critically assess a critical infrastructure system's vulnerability to extreme natural events and climate change. In most cases, transportation infrastructure is designed to withstand either the most extreme or close to the most extreme event that will add abnormal stresses on a physical structure. The system may fail to perform as intended if the physical structure faces an event larger than what it is designed for. The results of the transportation study demonstrate that all categories of roadways are vulnerable to climate change and that the magnitude of bridge vulnerability to future climate change is variable depending on which climate model projection is used. Results also show that urbanization and land use patterns affects the susceptibility of the bridge to failures. Similarly, results of the water study indicate that the WMA water supply system may suffer from water shortages accruing due to future droughts but climate change is expected to improve water supply reliability due to an upward trend in precipitation and streamflow. / Ph. D.

The overall process of water treatment is a compilation of various unit processes including: aeration, disinfection, the mixing of chemicals, flocculation, sedimentation, and filtration. The arrangement of these various unit processes into different treatment configurations provided the basis for laboratory-scale experimentation in which the zeta potential, turbidity, alkalinity, and pH were monitored to determine the optimum operating mode for the Carvins Cove water treatment plant in Virginia during June and July, 1979. Results indicated that none of the treatment configurations tested produced significantly different results. Marginal improvement in turbidity removal was accomplished when alum was added after aeration rather than before aeration. The use of aeration did not significantly affect the coagulation process. Rapid mixing of the alum with a jar test apparatus did not significantly affect the turbidity removal achieved. The cationic polymer, CatFloc T, did not reduce the low turbidity of the raw water. / Master of Science

Techniques were developed for the purpose of applying soil and water conservation structure designs utilized in the United States for use in Thailand. Design parameters currently being used in the United States were first studied and evaluated as to their development and application. The range of application of the various soil and water conservation structures were determined. This process included an evaluation of the soil types, land use, topography, and climatic factors in terms of their effect on the types of soil and water conservation structure designs to be utilized. Since the parameters may act separately or in various combinations, design limits are essential for each one. In the second step of the study, all available survey data applicable in characterizing these same parameters in Thailand were assembled and analyzed for each region. From this analysis, design ranges and the limits for each factor were estimated, based on the research and experience in the United States. Particular attention focused on the research of Beasley and the research compiled in the Engineering Field Manual. Finally, these estimated design values for Thailand's conditions were substituted in United States formulae. From these substitutions, other design procedures for model designs of several major engineering soil and water conservation structures were developed. / Master of Science