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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Complex Adaptive Systems Simulation-Optimization Framework for Adaptive Urban Water Resources Management

Giacomoni, Marcio 2012 August 1900 (has links)
Population growth, urbanization and climate change threaten urban water systems. The rise of demands caused by growing urban areas and the potential decrease of water availability caused by the increase of frequency and severity of droughts challenge the continued well-being of society. Due to increasing environmental and financial constraints, water management paradigms have shifted from supply augmentation to demand management, and water conservation initiatives may efficiently decrease water demands to more sustainable levels. To provide reliable assessment of the efficiencies of different demand management strategies, new modeling techniques are needed that can simulate decentralized decisions of consumers and their interactions with the water system. An integrated simulation-optimization framework, based on the paradigm of Complex Adaptive Systems, is developed here to model dynamic interactions and adaptations within social, built, and natural components of urban water systems. The framework goes beyond tradition engineering simulations by incorporating decentralized, heterogeneous and autonomous agents, and by simulating dynamic feedback loops among modeling components. The framework uses modeling techniques including System Dynamics, Cellular Automata, and Agent-based Modeling to simulate housing and population growth, a land use change, residential water consumption, the hydrologic cycle, reservoir operation, and a policy/decision maker. This research demonstrates the applicability of the proposed framework through a series of studies applied to a water supply system of a large metropolitan region that is located in a semi-arid region and suffers recurrently from severe droughts. A set of adaptive demand management strategies, that apply contingency restrictions, land use planning, and water conservation technologies, such as rainwater harvesting systems, are evaluated. A multi-objective Evolutionary Algorithm is coupled with the CAS simulation framework to identify optimal strategies and explore conflicting objectives within a water system. The results demonstrate the benefits of adaptive management by updating management decisions to changing conditions. This research develops a new hydrologic sustainability metric, developed to quantify the stormwater impacts of urbanization. The Hydrologic Footprint Residence captures temporal and spatial hydrologic characteristics of a flood wave passing through a stream segment and is used to assess stormwater management scenarios, including Best Management Practices and Low Impact Development.
52

HYDROLOGIC CHARACTERIZATION OF A RAIN GARDEN MITIGATING STORMWATER RUNOFF FROM A COMMERCIAL AREA

McMaine, John T 01 January 2013 (has links)
Impervious surfaces such as roads, sidewalks, and roofs increase the volume of runoff generated in a watershed. Traditional stormwater management techniques emphasize conveyance of runoff away from impervious surfaces in order to reduce flooding. Rain gardens are becoming popular as a different means to manage stormwater in such a way that runoff is captured and infiltrated onsite rather than conveyed offsite. A stormwater management system consisting of a rainwater harvest system, rain garden, and infiltration chamber was built at the Coca-Cola Refreshments USA, Inc. distribution center in Lexington, Kentucky during the fall of 2011. Precipitation, inflow, and water level were measured from May, 2012 to April, 2013 to evaluate the hydrologic performance of the rain garden. The rain garden had a high infiltrative capability and was able to capture and infiltrate 100% of the runoff generated during the study period. The results of the study were used to formulate recommendations for rain garden design and construction in central Kentucky.
53

Understanding the relationship between urban best management practices and ecosystem services

McDonough, Kelsey R. January 1900 (has links)
Master of Science / Biological & Agricultural Engineering / Stacy L. Hutchinson / Increasing attentiveness to climate change and the dependence of human life on natural resources has spurred awareness about the detrimental impacts of human activity on the environment. Ecosystem services, or the benefits that humans derive from ecosystems, have changed more in the past 50 years than in any other comparable period in human history (Carpenter et al., 2009).The dilemma of managing the trade-off between immediate human needs and maintaining the ability of the Earth to provide ecosystem services is considered to be one of the largest challenges of this century (Foley et al., 2005). The ecosystem service concept aims maximize the provision of services across an entire ecosystem to achieve overall ecosystem health through land management, policy, and economic decisions. The intent of this research was to improve such decisions by increasing the understanding about the relationship between urban best management practices and freshwater provision, erosion regulation, and flood regulation ecosystem services. Fifty-six land management scenarios with varying densities of BMP application were simulated using the Stormwater Management Model (SWMM). The ecosystem services resulting from these land management scenarios were quantified using indices developed by Logsdon and Chaubey (2013). Results demonstrate that the application of bioretention cells improve both freshwater provision and erosion regulation services immediately downstream from the implementation site, and an increase in erosion regulation services was observed at the greater watershed scale. There was no change in the provision of freshwater, erosion regulation, or flood regulation services observed by the application of green roofs or rain barrels at either scale of analysis.
54

Green Infrastructure: The Landscape of Urban EcoHousing

Upchurch, Meredith 11 July 2006 (has links)
Cities are facing environmental crises like never before, with problems of excess water runoff, degraded water quality, air pollution, and energy use reaching critical levels. The development of urban areas and the built environment is the primary cause of these problems and the built environment needs to be a part of the solution. This design thesis project produces a prototype design for the Urban EcoHousing development on a city block in Alexandria, Virginia. Design goals for the project connect the "Ecological Services of the Urban Landscape" to the "Rights of the Urban EcoHousing Resident" to create livable green spaces that can serve ecological functions and give the residents spaces to use. A comparison study with a conventional housing development at the same location illustrates that ecohousing can meet the requirements of the conventional development while providing superior results for the residents and the environment. / Master of Landscape Architecture
55

Porous Concrete: Proposal of UA Study and Best Practices

Foster, Shiloh January 2016 (has links)
Sustainable Built Environments Senior Capstone Project / Porous concrete pavements have been used in the eastern United States to effectively manage storm water when used as an alternative to impervious surfaces. This paper reviewed a wide body of available literature and research to examine their potential to reduce runoff at the University of Arizona. This study found that their unique structural properties enable them to infiltrate and detain large volumes of water in a stone sub-base below the slab, filtering out many street related contaminants without the need to install additional infrastructure. Porous concrete surfaces may support green development in the southwest where water is both a sensitive and valuable resource. However, long-term structural durability, clogging potential due to dust, and maintenance requirements have yet to be fully understood in this region. This paper then summarizes critical factors that affect the performance of porous concrete and proposes a framework for future study to be conducted by the University of Arizona in a way that would reduce runoff to major campus roads, contribute to a better understanding of sustainable storm water management in the southwest, and demonstrate leadership in environmental stewardship.
56

Performance and Operation of Partial Infiltration Permeable Pavement Systems in the Ontario Climate

Drake, Jennifer Anne Pauline 09 July 2013 (has links)
Partial-infiltration permeable pavement (PP) systems provide environmental benefits by increasing infiltration, attenuating storm flows and improving stormwater quality. This thesis focuses on the performance and operation of partial-infiltration PP systems over low permeability soil in Ontario. Three PP, AquaPave®, Eco-Optiloc® and Hydromedia® Pervious Concrete were monitored over two years and their performance was evaluated relative to an impermeable Asphalt control. Field data was collected from the Kortright PP pilot parking lot in Vaughan, Ontario. Through the use of restrictor valves on underdrains the PP systems were shown to provide substantial hydrologic benefits by eliminating stormwater outflow for rain events less than 7mm, reducing peak flows by 91% and reducing total stormwater volume by 43%. Stormwater quality was analyzed for winter and non-winter seasons. The PP were shown to greatly reduce the concentration and total loading of suspended solids, nutrients, hydrocarbons and most heavy metals. Some water quality data, such as pH, K, or Sr levels, indicate that the quality of PP effluent will change as the system ages. Study of PP sample boxes at the University of Guelph highlighted the role that construction materials have on effluent quality and showed that pollutants introduced by the pavement and aggregate are almost entirely in a dissolved form and decline very rapidly after a season of exposure to rainfall. Benefits to water quality were sustained during winter months. The partial-infiltration PP systems were shown to provide buffering of Na and Cl concentrations. Small and large-scale maintenance practices for PP systems were investigated. Small-sized equipment testing found that vacuum cleaning and pressure-washing have good potential to improve infiltration capacity. Testing of full-sized streetsweeping trucks demonstrated that permeability can be partially restored on PICP by suction-based sweeping. Vacuum-sweeping was beneficial on a PC pavement which had experienced large permeability losses. Results of this study indicate that partial-infiltration PP systems can be effective measures for maintaining or restoring infiltration functions on parking lots and other low volume traffic areas, even in areas with low permeability soils.
57

Feasibility and life cycle assessment of decentralized water, wastewater, and stormwater alternatives for residential communities with a variety of population densities

Jeong, Hyunju 12 January 2015 (has links)
Centralized infrastructure (CI) is difficult to sustain with limited water and fossil fuel resources because CI withdraws 100% of water demand from the environment as an open-loop system and electricity is consumed to transport and treat water and wastewater while demand is increasing. Hybrid infrastructure (HI) is proposed to combine CI with decentralized alternatives such as low impact development (LID) technologies (i.e., xeriscaping, rain gardens, and rainwater harvesting) or greywater reclamation systems with membrane bioreactors (MBRs). Water, wastewater, and stormwater systems in the City of Atlanta (COA) were regarded as CI. HI was compared to CI using life cycle environmental impacts measured by water reuse index (WRI) and life cycle assessment (LCA) scores. WRI is a ratio of water withdrawal to sustainable water resources of wastewater (i.e., return flow) and stormwater discharge, which presents water stress level (e.g., 0.2 ~ 0.4: medium-high level). LCA score is determined as % of annual world average environmental damage per capita. As stormwater runoff, water demand, greywater generation, rainwater harvesting, etc. vary depending on land use and population density, feasibility of decentralized alternatives was evaluated in eleven residential communities. Five single-family residential communities were designated as between R-1 of 16 people/10 acres and R-5 of 169 people/10 acres and six multi-family residential communities were designated as between RG-1 of 148 people/10 acres and RG-6 of 5,808 people/10 acres. HI with LID technologies reduced WRI of COA that relies on CI from 0.45 to 0.12. HI reduced the LCA scores of CI with combined sewer system (CSS) by between 1% for RG-6 and 68% for R-1 and the LCA scores of CI with separate sewer system (SSS) by between 0% for RG-6 and 18% for R-1. As population density increases for the multi-family residential communities, harvested rainwater decreases and a small amount of water demand is satisfied. Consequently, it has a negligible impact on the LCA scores in RG-6. HI with greywater reclamation system reduced WRI of COA from 0.45 to 0.35. HI resulted in the LCA scores greater as compared to CI in the five single-family communities and RG-1, RG-2, and RG-3 because of the electricity consumption of small-scale MBR. However, the electricity consumption per kgal decreases with increasing MBR treatment capacity and the LCA scores were reduced by 5% for RG-4, 15% for RG-5, and 21% for RG-6. The MBR treatment capacity of RG-4 is 15.6 kgal/day.
58

Desenvolvimento de baixo impacto aplicado ao processo de planejamento urbano

Tavanti, Débora Riva 15 February 2009 (has links)
Made available in DSpace on 2016-06-02T20:00:37Z (GMT). No. of bitstreams: 1 3523.pdf: 12073466 bytes, checksum: 878f935338c5beb08fa768751f31d082 (MD5) Previous issue date: 2009-02-15 / Urbans areas even biggens are becoming impermeabilized reducing the soil`s infiltration rate and increasing the velocity and volume of runoff, changing meaningly the hydrological cycle and causing floods. A set of techniques able to create hydrologically functional landscape can be found at Low Impact Development (LID) that works just similar to the natural, becoming possible the development of projects adapted to the natural topography, maintaining the yield of the lot and the local hydrological function; aiming at esthetics valorization and stormwater control management with low cost. This study makes use of this methodology since the beginning of the planning process, working at the some time with urban, environmental and hydrological aspects, intending to recuperate or even to keep the pre-development behavior of the area. To support the local hydrology, reduce sealing, keeping time to concentrate, to keep Fingerprinting, enhance infiltration, among others. It compares the predevelopment conditions, the conventional urbanization and that with LID techniques related to aspects mentioned to a specifc area at UFSCar Campus, São Paulo. This search revealed that is possible to have an urban planning using LID, with urban, environmental and hydrological advantages in the opposite to the conventional development systems, such as the increase of permeable areas, vegetation areas and the reduction of peak discharge and stormwater runoff. Low impact development makes these interventions in a simultaneous way just to re-establish the pre-existents conditions, and then to make use of integrated management`s practice. / Áreas urbanas cada vez maiores são impermeabilizadas, reduzindo a capacidade de infiltração do solo e acelerando a velocidade do escoamento superficial, alterando significativamente o ciclo hidrológico, e gerando inundações. Encontra-se no Desenvolvimento de Baixo Impacto (Low Impact Development, LID), um conjunto de técnicas capazes de criar paisagens hidrologicamente funcionais, com comportamento similar ao natural, facilitando o desenvolvimento de planos adaptados a topografia natural, mantendo o rendimento do lote e as funções hidrológicas do local; visando a valorização estética e a gestão de controle de águas pluviais menos custosas. Este trabalho utiliza-se desta metodologia desde o início do processo de planejamento, trabalhando concomitantemente os aspectos urbanísticos, ambientais e hidrológicos, de modo a recuperar e/ou manter o comportamento hidrológico de pré-ocupação da área. Os recursos são, manter hidrologia local, reduzir impermeabilização, manter o tempo de concentração, manter as digitais locais, potencializar infiltração, dentre outros. Comparam-se as condições de pré-ocupação, urbanização convencional e urbanização com técnicas de LID, quanto aos aspectos mencionados para uma área do Campus da UFSCar, em São Carlos/SP. Como resultado essa pesquisa revelou que o planejamento urbano utilizando-se de técnicas de baixo impacto é possível, apresentando vantagens urbanísticas, ambientais e hidrológicas sob os sistemas de desenvolvimento convencionais, tais como aumento das áreas permeáveis, das áreas de cobertura vegetal, redução da vazão de pico e do volume de escoamento superficial. O desenvolvimento de baixo impacto realiza estas intervenções de forma simultânea para restabelecer as condições pré-existentes, e só então, empregar práticas de gerenciamento integrado.
59

Desenvolvimento de baixo impacto aplicado ao Campus Samambaia da Universidade Federal de Goiás / Low impact development applied te the Campus Samambaia of the Universidade Federal de Goiás

Silva, Gerani Félix do Nascimento 27 March 2015 (has links)
Submitted by Cláudia Bueno (claudiamoura18@gmail.com) on 2015-10-29T17:22:34Z No. of bitstreams: 4 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Dissertação - Gerani Félix do Nascimento Silva - 2015 parte 1.pdf: 14003895 bytes, checksum: 1deef8b843839e931401fd2687855c7a (MD5) Dissertação - Gerani Félix do Nascimento Silva - 2015 parte 2.pdf: 11378546 bytes, checksum: d119c2bfab445495905e8a4e315c0fb7 (MD5) Dissertação - Gerani Félix do Nascimento Silva - 2015 parte 3.pdf: 19840456 bytes, checksum: 7cb224299c4954791ef2b6e2ec860633 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-11-03T14:18:54Z (GMT) No. of bitstreams: 4 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Dissertação - Gerani Félix do Nascimento Silva - 2015 parte 1.pdf: 14003895 bytes, checksum: 1deef8b843839e931401fd2687855c7a (MD5) Dissertação - Gerani Félix do Nascimento Silva - 2015 parte 2.pdf: 11378546 bytes, checksum: d119c2bfab445495905e8a4e315c0fb7 (MD5) Dissertação - Gerani Félix do Nascimento Silva - 2015 parte 3.pdf: 19840456 bytes, checksum: 7cb224299c4954791ef2b6e2ec860633 (MD5) / Made available in DSpace on 2015-11-03T14:18:54Z (GMT). No. of bitstreams: 4 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Dissertação - Gerani Félix do Nascimento Silva - 2015 parte 1.pdf: 14003895 bytes, checksum: 1deef8b843839e931401fd2687855c7a (MD5) Dissertação - Gerani Félix do Nascimento Silva - 2015 parte 2.pdf: 11378546 bytes, checksum: d119c2bfab445495905e8a4e315c0fb7 (MD5) Dissertação - Gerani Félix do Nascimento Silva - 2015 parte 3.pdf: 19840456 bytes, checksum: 7cb224299c4954791ef2b6e2ec860633 (MD5) Previous issue date: 2015-03-27 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / Conventional urban drainage, defined as a system based on rapid flow of rainwater, has been proven unsustainable. Due to increase in waterproof surfaces resulting from urban sprawl, repeated floods and flooding have been occurring, especially in more densely populated areas. In order to restore the hydrological functions of the place, the development of low impact in urban water management, in this study called low impact development (LID), aims at achieving efficiency in the protection of natural resources and meet environmental regulations in urban planning. To apply LID to Campus Samambaia, of the Universidade Federal de Goiás (UFG), since the initial urban planning and also in areas previously consolidated, compensatory techniques in urban drainage were studied based on the concept of LID. This campus was chosen as a case study because of the great densification that has been taking place there, due to the large injection of funds from the Programa de Apoio a Planos de Reestruturação e Expansão das Universidades Federais (Reuni) in the country, from 2008 to 2013, with increased impervious surfaces, reaching 45.5% of its area. To perform this study, a broad literature review on the topic, field visits, and a case study were carried out. This research sought to initially understand the relationship between urban planning and stormwater drainage. The documentary research revealed the grounds of the laws and regulations governing urban planning, drainage within the sanitation context, as well as the master plans of federal institutions of higher education (IFES) in an interface with urban stormwater drainage. Furthermore, based on the review of guides, technical manuals, articles, theses, and dissertations on the subject, the operation of compensatory techniques was detailed, subject to the limitations regarding environmental, sanitary, landscape, and technical aspects. Field visits were made to the Campus Samambaia and a field visit to the Campus São Carlos, of the Universidade Federal de São Carlos (UFSCar), in its experimental watershed, where several compensatory techniques are implemented in full scale, as a result of research trials. After confirming the feasibility of using structural and non-structural compensatory techniques at the Campus Samambaia, at the end of this study proposal guidelines were systematized for implementation in two scenarios, with 45.5% and 85.5% of impervious surfaces, the latter representing the limit allowed by the master plan of Goiânia. These recommendations were intended as a reference to the actions of both the physical expansion of UFG and future studies and similar applications. / A drenagem urbana convencional, conceituada como um sistema baseado no rápido escoamento das águas pluviais, tem se mostrado insustentável. Por conta da crescente impermeabilização resultante da expansão urbana, tem havido repetidas ocorrências de inundações e alagamentos, em especial nos espaços mais adensados. Com o intuito de restaurar as funções hidrológicas do lugar, o desenvolvimento de baixo impacto na gestão das águas urbanas, tratado neste trabalho como low impact development (LID), visa atingir a eficiência na proteção dos recursos naturais e atender às regulamentações ambientais no planejamento urbano. Com o objetivo de aplicar o LID ao Campus Samambaia, da Universidade Federal de Goiás (UFG), no município de Goiânia, GO, desde o planejamento urbano inicial e também em espaços já consolidados, foram estudadas técnicas compensatórias em drenagem urbana dentro do conceito LID. Esse campus foi escolhido como estudo de caso por ter ali ocorrido grande adensamento, fruto da ampla injeção de recursos oriundos do Programa de Apoio a Planos de Reestruturação e Expansão das Universidades Federais (Reuni) no país, no período de 2008 a 2013, com incremento de áreas impermeáveis, alcançando 45,5% de sua área de ocupação. Para a consecução deste trabalho, foram realizados ampla revisão de literatura sobre o tema, visitas de campo e estudo de caso. Nesta pesquisa, inicialmente buscou-se compreender a relação existente entre planejamento urbano e drenagem de águas pluviais. Por meio de pesquisa documental, evidenciou-se a fundamentação das leis e normativas que regulamentam o planejamento urbano, a drenagem dentro do saneamento básico, bem como os planos diretores de instituições federais de ensino superior (IFES) em interface com a drenagem urbana de águas pluviais. Para além disso, com base na revisão de guias, manuais técnicos, artigos, teses e dissertações sobre o tema, detalhou-se o funcionamento das técnicas compensatórias, observando-se as limitações em aspectos ambientais, sanitários, paisagísticos e técnicos. Foram realizadas visitas de campo ao Campus Samambaia e uma visita de campo ao Campus São Carlos, da Universidade Federal de São Carlos (UFSCar), em sua bacia hidrográfica experimental, na qual várias técnicas compensatórias estão implantadas em escala real como resultado de pesquisas científicas. Confirmada a viabilidade do uso de técnicas compensatórias estruturais e não estruturais no Campus Samambaia, ao final deste estudo foram sistematizadas proposições de diretrizes, com orientações para a sua implantação em dois cenários, com 45,5% e 85,5% de área impermeável, sendo este último o limite permitido pelo plano diretor de Goiânia. Tais recomendações visaram servir de referência para as ações tanto de expansão física da UFG quanto para estudos futuros e aplicações semelhantes.
60

Homeowner Willingness to Adopt Low-Impact Development Practices in the Ipswich River Watershed: Opportunities and Barriers

Stacy, Johanna R 17 July 2015 (has links)
The Ipswich River watershed has experienced increasing urbanization in recent years. The river, which supplies water to over 300,000 residents (twice the watershed’s population), was considered one of the 10 Most Endangered Rivers in the U.S. in 2003 due to seasonal low-flow and no-flow events. Seasonal outdoor water restrictions have curbed residential demand; however, impervious surfaces and municipal sewer systems direct much of the runoff outside the watershed. Low-impact development (LID) practices, specifically those that infiltrate runoff, have the potential to keep more water in the watershed, and increase baseflows in the river. This study seeks to ascertain the barriers and motivations that exist to LID adoption. A paper survey including Likert-scale questions and a photo preference component was sent to 1,000 homeowners in the watershed. Analysis of responses employed factor analysis and means comparisons to compare responses between concerned homeowners (those who belonged to the local watershed association) and randomly-selected homeowners. Income and educational attainment were significant variables in both aesthetic preferences and willingness to adopt LID practices. Perceived cost of landscape changes and concern about disease-carrying pests also surfaced as barriers to residential adoption. The findings emphasize alternate strategies for land use planners, landscape professionals and environmental organizations to promote behavioral changes in the way residential landscapes are managed, and policies municipalities could adopt to implement more widespread use of LID practices. More widespread understanding and appreciation of the multiple benefits of rain LID landscapes could also serve all three groups.

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