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Trincheiras de infiltração como tecnologia alternativa em drenagem urbana: modelagem experimental e numérica / not availableMelissa Cristina Pereira Graciosa 17 June 2005 (has links)
A infiltração das águas de chuva dentro dos lotes urbanos é uma possível forma de promover o controle descentralizado do escoamento superficial na origem, com vistas ao gerenciamento das águas pluviais urbanas e conseqüente atenuação das cheias. Neste trabalho, foram conduzidos ensaios de campo com trincheiras de infiltração, em dois solos distintos, um arenoso e outro argiloso, com o objetivo de avaliar quantitativamente o comportamento hidráulico das estruturas de infiltração em resposta a volumes de escoamento. As trincheiras foram alimentadas com volumes de água controlados, e o campo de umidade do experimento foi monitorado com sonda de nêutrons, durante o processo de redistribuição da água no solo. Foi realizada a modelagem matemática do fenômeno bidimensional de infiltração em torno de trincheiras de seção retangular, em resposta à entrada de águas pluviais provenientes de áreas impermeabilizadas contíguas. A comparação entre os resultados experimentais e simulados pela equação bidimensional de Richards indica uma pequena defasagem dos valores de volume infiltrado e umidade do solo nos processos de infiltração e drenagem interna simulados em relação aos observados. A capacidade de infiltração da trincheira mostrou-se maior nos dados observados, possivelmente devido à simplificação de distribuição unimodal dos diâmetros dos poros adotada na modelagem numérica, uma vez que, experimentalmente, observou-se multimodalidade nos dois solos estudados. A curva de van Genuchten é, juntamente com a equação de Richards, a base do modelo computacional, e divergências no seu ajuste em relação aos dados observados podem conduzir a pequenas divergências dos volumes infiltrados e perfis de umidade ao longo do processo de infiltração simulado, em relação ao observado. São apresentadas algumas considerações de dimensionamento sobre a implantação de trincheiras de infiltração em lotes residenciais, bem como discussões com respeito aos planos diretores urbanos. É apresentado um estudo simplificado, baseado no método racional, sobre a redução no hidrograma de cheia proporcionada pelo uso de trincheiras em uma micro bacia urbana, o qual revelou reduções da ordem de até 94% do deflúvio superficial direto gerado pelo lote. / Stormwater infiltration process at the scale of housing is a possible way to promote the decentralized runoff control in order to manage the urban water and to attenuate flood peaks. In this work, field essays with infiltration devices at two different soils, either sandy and clay-loam soils, are assessed in order to study the hydraulic behavior of infiltration trenches to attenuate incoming runoff volume inputs. The infiltration trench experiments set a controlled water supply for specific boundary conditions, and the experimental moisture field were monitored with neutron probe during the water redistribution process at soil core. Bi-dimensional (2D) mathematical modeling is depicted at specific boundary conditions with a rectangular-trench layout, thereby mimicking a potential situation of runoff incoming from adjacent impervious areas. The comparison between experimental and numerical results, simulated by two-dimensional Richards\' equation, shows a small lag-time difference of both infiltrated volumes and soil moisture contents during infiltration and drainage periods. The trench infiltration capacity of observed data appears to be greater than simulated results, possibly due to an overall simplification of a uni-modal, homogeneous pore diameter distribution adopted by the modeling scheme. Experimental retention curves outline indirect evidences of multi-modal, heterogeneous behavior of pore structure. Bon van Genutchen-type retention curve and Richards-momentum equations represent the baseline approach to the computational model of non-saturated soils. Some fitting discrepancies between observed and simulated results could lead to negligible different estimations of infiltrated volumes and moisture profiles. Finally, further discussions on project design and best management practices (BMPs) of infiltration trenches at housing scale as well discussions on urban master plan are outlined herewith. A simplified study, based on rational method, is presented on the reduction of incoming hydrograph with the use of infiltration trenches. Preliminary results perform volume reductions of approximately 94% from incoming runoff generated at housing lots.
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Evidence Supporting Treatment Practice Based Delineation of Stormwater Runoff ZonesGorski, Jacob J. 01 October 2013 (has links)
Particles mobilized by stormwater negatively affect receiving surface waters. Stormwater best management practices (BMPs) can reduce solids along with associated pollutants in runoff but engineers and environmental managers have been long vexed by the problem of choosing the optimal BMP for a given situation. A common BMP process for solids removal is sedimentation. This thesis addresses the question of whether the effectiveness (and thus choice) of a sedimentation device can be estimated (and thus optimized) from the particle size properties of runoff, which, in turn, could be associated with specific runoff zones or land uses. Presented here is a series of experiments to determine the solids-removal capabilities of a manufactured oil-water separator that also removes solids via sedimentation. A statistical model developed from the experimental data shows that, under normal operating conditions, influent particle size can be used to accurately estimate effluent total suspended solids (TSS) for BMPs of this type. Relationships between particle size and particle-bound metal concentrations for Cu, Zn and Pb were then obtained from the literature and incorporated into the model to allow estimates of metal removal efficiencies based on TSS and PSD. The model can be used with an arbitrary particle size distribution (PSD); this allows effluent quality predictions to be made considering that particle sizes entering stormwater BMPs could vary due to anthropogenic, hydraulic or hydrologic factors. To place these experimental and modeling results in the context of an urban environment, samples of deposited stormwater solids were collected from residential areas, commercial areas and an industrial zone in Portland, Oregon, and the PSD of each sample was determined using light obstruction particle sizing. PSDs ranging over sizes from 3μm to 200μm vary among these locations. Areas with high anthropogenic impact were found to have PSDs skewed toward the smallest particle sizes. The statistical model developed here was then used to show that the effluent quality of the BMP tested would differ depending on the locations where solids were collected. The evidence presented in this thesis thus indicates that device performance will correlate with geographic locations or land use zone and validates further investigation into delineating the City of Portland's characteristic runoff zones and using the runoff characteristics of each zone to map it to the most desirable treatment practices.
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Design of Low Impact Development and Green Infrastructure at Flood Prone Areas in the City of Miami Beach, FLORIDA, USAAlsarawi, Noura 29 June 2018 (has links)
This thesis investigates the effectiveness of Low Impact Development Infrastructure (LIDI) and Green Infrastructure (GI) in reducing flooding resulting from heavy rainfall events and sea-level rise, and in improving stormwater quality in the City of Miami Beach (CMB). InfoSWMM was used to simulate the 5, 10, and 100-year, 24-hour storm events, total suspended solids (TSS), biochemical oxygen demand (BOD), and chemical oxygen demand (COD) loadings, and in evaluating the potential of selected LIDI and GI solutions in North Shore neighborhood.
Post-development results revealed a decrease of 48%, 46%, and 39% in runoff, a decrease of 57%, 60%, and 62% in TSS, a decrease of 82%, 82%, and 84% in BOD, and a decrease of 69%, 69%, and 70% in COD loadings. SWMM 5.1 was also used to simulate the king tide effect in a cross section in Indian Creek Drive. The proposed design simulations successfully demonstrated the potential to control flooding, showing that innovative technologies offer the city opportunities to cope with climate impacts. This study should be most helpful to the CMB to support its management of flooding under any adaptation scenarios that may possibly result from climate changes. Flooding could be again caused as a result of changes in inland flooding from precipitation patterns or from sea-level rise or both.
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The assessment of copper and zinc removal from highway stormwater runoff using Apatite II™Huang, Hsiao-Wen 31 May 2012 (has links)
Copper and zinc are heavy metals commonly present in highway stormwater runoff. Discharge of these metals to surface waters inhabited by sensitive aquatic species including threatened and endangered salmonids has necessitated the need for improved treatment techniques. Although copper is of the greater toxicological concern, zinc is often present at concentrations several times higher than copper and may compete with copper during adsorptive treatment processes. In the current study, the ability biogenic fish-bone based alternative adsorbent, Apatite II™, for copper and zinc removal from synthetic stormwater runoff was evaluated. Batch experiments were employed to examine equilibrium removal and rapid small scale column tests (RSSCT) were used to simulate dynamic operation in continuous systems. In both batch and continuous systems, the release of phosphate and calcium were observed, and Apatite II™ achieved high removal efficiencies. The removal of copper and zinc was likely due to a combination of processes including adsorption, ion exchange and precipitation. Precipitation played a dominant role in copper removal and the release of phosphate and pH buffering appear to drive this process. While precipitation was also quite important for zinc removal, adsorptive removal also played a role. The findings from the current study provide a general understanding of the performance of copper and zinc removal from stormwater runoff using Apatite II™. / Graduation date: 2012
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Åtgärdande av felkopplingar som kompensationsåtgärd för ökade dagvattenföroreningar : en fallstudie med en kostnads-nyttoanalys / Fixing incorrect connections in sewage pipes as a compensatory measure for increasing levels of stormwater pollutants : a case study with a cost-benefit analysisBozorgi, Rozbe January 2018 (has links)
Weserdomen 2015 resulterade i en strängare tolkning av EU:s ramdirektiv för vatten vilket bland annat innefattade att inga exploateringar får tillåtas om dessa medför att minst en kvalitetsfaktor i vattnet får en sämre statusklass, oavsett hur övriga kvalitetsfaktorer påverkas. Den strängare tolkningen, i kombination med en ökad urbaniseringsgrad, ställer högre krav på samhällets hantering av spill- och dagvatten. Ett vanligt sätt att säkerställa ovanstående krav är att tillämpa olika lösningar för lokalt omhändertagande av dagvatten (LOD). Syftet med dessa lösningar är att hantera dagvattnet så nära uppkomstkällan som möjligt. I vissa fall kan det dock tänkas att det finns mer effektiva åtgärder för att säkerställa god vattenstatus. En åtgärd som syftar till att kompensera för frånvarandet av en annan åtgärd kallas för kompensationsåtgärd. I det här examensarbetet har fallet med att spåra och åtgärda felkopplingar i ledningsnätet (spillvatten kopplat på dagvattennätet) undersökts som kompensationsåtgärd för LOD. Den specifika LOD-lösning som använts i arbetet har varit dagvattendammar. Examensarbetet har utrett rådande lagstiftning vad gäller kompensationsåtgärder samt gjort en fallstudie för Bällstaån med en kostnads-nyttoanalys där åtgärdandet av felkopplingar jämförts med anläggandet av dagvattendammar. Resultatet av undersökningarna visade att kompensationsåtgärder idag är ett begrepp som kan tolkas olika, där det även i domstolen genom åren har tolkats olika. Nuvarande praxis är dock att en kompensationsåtgärd inte kan åberopas för att tillåta en exploatering som annars hade funnit avslag. Att kunna nyttja åtgärdandet av felkopplingar som kompensationsåtgärd för LOD är således, med dagens regelverk, väldigt osannolikt. Fallstudien visade att åtgärdandet av felkopplingar, med avseende på vattenkvalitet är en betydligt mer kostnads-nyttoeffektiv åtgärd i jämförelse med anläggandet av dagvattendammar. Bristen på studier och utredningar på felkopplingar av denna typ är, mot bakgrund av fallstudien, förmodligen en indikator på att mer resurser bör läggas inom detta område. / In 2015 the Weser Case resulted in a more stringent interpretation of the EU Water Framework Directive. For instance, the ruling stated that no projects should be given permission if even as little as one quality factor ends up with a lower status, regardless of how the other quality factors are affected. The stricter interpretation, combined with an increasing grade of urbanization, places higher demands on society’s management of wastewater and stormwater. One common way of ensuring the above requirements is to apply different solutions of best management practices for stormwater (BMP). The purpose of these solutions is to process the water as close to the source of origin as possible. However, in some cases it may be that there are more effective measures to ensure good water quality. A measure taken with the purpose of compensating for the absence of a different action is called a compensatory measure. In this thesis, the case of fixing incorrect connection of sewage pipes (where wastewater pipes have been incorrectly connected to stormwater pipes) was investigated as a compensatory measure for stormwater ponds (a common BMP). The prevailing legislation regarding compensatory measures was analysed and a case study has been conducted for Bällstaån. The case study included a cost-benefit analysis where the fixing of incorrectly-connected sewage pipes was compared with the implementation of stormwater ponds. The investigation regarding the legislative aspect showed that compensatory measures are a concept that can be interpreted somewhat differently. This has also been the case in the court over the years. However, current practice shows that a compensatory measure cannot be invoked to allow a project that otherwise would have been refused. Being able to use the fixing of incorrect connections as a compensation for BMP is thus, with today’s regulation, very unlikely. The case study showed that fixing incorrect connections in sewage pipes is, with regard to water quality, a far more cost-beneficial measure compared to the construction of stormwater ponds. Furthermore, the lack of studies regarding this kind of incorrect connections is, in the light of the results from the case study, probably an indication that this is a problem that fairly few people work with and where more resources could be a good investment for future water quality.
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Serviço público de drenagem e manejo de águas pluviais urbanas : avaliação do contexto brasileiro e da adaptabilidade de práticas norte-americanas para a proposição de melhorias institucionais e financeirasColombelli, Karina January 2018 (has links)
A drenagem urbana é o componente do saneamento básico menos assistido no Brasil em termos de regulação e até mesmo de regulamentação direta pelo Titular. Embora a Lei nº 11.445/2007 tenha estabelecido, expressamente, o manejo de águas pluviais urbanas como um dos quatro pilares do saneamento básico, a estrutura institucional relacionada à prestação e à regulação deste serviço ainda não está consolidada e a normatização existente é parca e dispersa. Na maioria dos casos, não existe órgão regulador para o serviço de drenagem urbana, e sua prestação dá-se diretamente por secretarias de prefeituras municipais, que, não raro, encontram-se defasadas em termos de estrutura, qualificação técnica e recursos financeiros, faltando ainda integração do manejo de águas pluviais urbanas com a gestão de recursos hídricos e dos serviços de abastecimento de água, esgotamento sanitário e resíduos sólidos. Assim, verifica-se que um dos maiores problemas a serem enfrentados no setor de drenagem urbana é a sua estruturação institucional, sendo necessário constituir entidades autônomas de prestação do serviço que o executem de forma planejada, integrada e com sustentabilidade econômico-financeira, bem como prever agências reguladoras para garantir a adequação do mesmo. O presente trabalho teve por objetivo formular propostas para a melhoria do serviço público de manejo de águas pluviais no Brasil com ênfase na questão institucional, a partir da análise dos contextos contemporâneos brasileiro e norte-americano de gestão deste serviço, observada a legislação aplicável e a busca pela autonomia financeira do prestador. Transversalmente, estudou-se o emprego de práticas sustentáveis de drenagem urbana, consideradas na elaboração das propostas Para o desenvolvimento deste trabalho, realizou-se pesquisa bibliográfica complementada por levantamento em campo das agências reguladoras brasileiras atuantes em drenagem urbana e visita técnica à ADASA – Agência Reguladora de Águas, Energia e Saneamento Básico do Distrito Federal. Após o exame detalhado dos contextos de gestão das águas pluviais no Brasil e nos Estados Unidos, concluiu-se que a macroestrutura regulatória deste país pode ser adaptada ao cenário brasileiro, desde que haja redução da escala espacial de atuação das entidades, que em território brasileiro não seriam agências reguladoras, e sim órgãos ambientais do SISNAMA. No que tange à prestação do serviço, constatou-se que o modelo estadunidense de utility (empresa de serviços públicos) tem se revelado eficaz, tanto para institucionalizar a figura do prestador, quanto para proporcionar sustentabilidade econômico-financeira. Outros aspectos da gestão norte-americana com aplicabilidade no Brasil foram identificados, e fizeram-se ainda proposições baseadas em parcas, porém exitosas, experiências nacionais de prestação e regulação sistemáticas. Dentre as propostas realizadas, destaca-se a orientação de que municípios de pequeno porte priorizem a prestação regionalizada do serviço público de drenagem urbana, alternativa esta que não só lhes permitiria elaborar um único Plano de Saneamento Básico, mas também abriria espaço para que o planejamento e a prestação do serviço ocorressem em escala de bacia hidrográfica, que é a ideal para o manejo de águas pluviais urbanas. / Urban drainage is the least assisted component of sanitation in Brazil in terms of regulation and even direct rulemaking by municipalities. Although Law Nº 11445/2007 expressly established the stormwater management as one of the four pillars of basic sanitation, the institutional structure related to the provision and regulation of this service has not yet been consolidated and existing regulations are few and dispersed. In most cases, there is no regulatory body for the urban drainage service, and it is provided directly by secretariats of municipal prefectures, which are often lagged in terms of structure, technical qualification and financial resources; thereto, it lacks integration of stormwater management with the water resources and water supply, sewage and solid waste services management. Thus, it is verified that one of the major problems to be faced in the urban drainage sector is its institutional structuring, and it is necessary to establish autonomous entities to provide this service in a planned, integrated and economically-financially sustainable way, as well as regulatory agencies to ensure its adequacy. The present work had the objective of formulating proposals for the improvement of the public stormwater management service in Brazil with emphasis on the institutional question, based on the analysis of the contemporary Brazilian and North American contexts of stormwater management, observing the applicable legislation and the the financial autonomy of the service’s provider. The use of sustainable urban drainage practices has been studied transversally and then considered in the preparation of the proposals For the development of this work, a bibliographical research was carried out complemented by field survey of the Brazilian regulatory agencies working in urban drainage and technical visit to ADASA - Regulatory Agency of Water, Energy and Basic Sanitation of the Federal District. After a detailed examination of the stormwater management contexts in Brazil and the United States, it was concluded that the regulatory macrostructure of this country can be adapted to the Brazilian scenario, since there is a reduction in the spatial scale of action of the entities, which in Brazilian territory would not be regulatory agencies, but environmental institutions of SISNAMA. Regarding the provision of the service, it was verified that the US utility model has proved to be effective, both to institutionalize the service provider and to afford economic-financial sustainability. Other aspects of US management with applicability in Brazil have been identified, and proposals have been made based on few but successful national experiences of systematic service rendering and regulation. Among the proposals made, it is important to point out that small municipalities should prioritize the regionalised provision of the urban drainage service, which would not only allow them to prepare a single Basic Sanitation Plan, but would also open space so that planning and service provision occur on a river basin scale, which is ideal for stormwater management.
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CONTROLE DA DRENAGEM NA FONTE E SUA COMPATIBILIZAÇÃO AO PLANO MUNICIPAL DE SANEAMENTO AMBIENTAL DE SANTA MARIA / CONTROL OF THE DRAINAGE IN THE SOURCE AND ITS COMPATIBILITY TO THE MUNICIPAL PLAN OF THE ENVIRONMENTAL SANITATION OF SANTA MARIA.Roman, Carlos Augusto 06 July 2015 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The City Hall of Santa Maria hired the Municipal Plan of Environmental Sanitation of Santa Maria
(MPLAENS), in relation to the urban drainage, one of the themes of the Plan. The Ministry of Cities encourages
the use of urban drainage practices that include as much approaches with compensatory techniques, as
approaches with principle of urban development of low impact. Thus, this research aimed to identify if the
(MPLAENS) incorporates proposals focused in the control of drainage in the source and how they are adressed.
The study was performed in three steps: initially, it was carried out the analysis of measures of control of the
storm water runoff proposed in (MPLAENS), in order to understand in which level were received the precepts of
measures of control of the storm water runoff at source (MCS). Afterwards, the feasibility of MCS for the city
has been verified, considering the restrictions of each device and the particularities of the urban occupation and
the hydrologic group of the soil. To provide subsidy for the future sizing of MCS, it was necessary an
intermediate step of determination of hydrologic parameters of sizing, such as, update of the relation intensityduration-
frequency (IDF), determination of value of the specific flow of predevelopment (Qpd) and the volume
of control (v). Based on definitions of control of the drainage at source, it is possible to affirm that, none of the
proposals of MPLAENS for the urban drainage meet the precepts of measures of control at source. From the held
observations in this study and the data available, it is possible to state that large extent of the urban perimeter of
the city has potential for the use of MCS. The suggestions presented in MPLAENS in relation to drainage consist
in the construction of approximately 631 km of drainage networks, besides the construction of approximately
180.000 m³ of anti-DSP deposit, being these distributed within the next twenty years of project of the Plan. For
an estimate of deployment of the micro drainage network, the authors of MPLAENS adopted the flow of 6,9
m³.s-1, calculated by the rational method with the use of the following parameters: Runoff coefficient (R) = 0,6;
Basin area (B) = 1,5 km²; Time of concentration (tc) = rain duration (t) = 1,63 hours; Time of return (Tr) = 10
years; Intensity of the rain (I) = 27,4 mm.h-1. To obtain the referent value of the intensity of the rain (I), the
authors used the Gumbel distribution of the data recorded by Instituto Nacional de Meteorologia (National
Institute of Meteorology). The IDF equation updated in this study and the same values of (t) and (Tr) used in
MPLAENS, results in a value of (I) = 42,72 mm.h-1 for this intensity, and for the same values of (R) and (B) the
result is a flow of 10,69 m³.s-1, value 56 percent higher than the present in MPLAENS. The potential of the
municipality for the deployment of MCS became evident through the results of this study, thus, the use of
drainage practices in small-scale spread over the whole river basin in order to reproduce or maintain the
hydrological conditions of predevelopment presents itself as a positive alternative. / A Prefeitura de Santa Maria contratou o Plano Municipal de Saneamento Ambiental de Santa Maria
(PLAMSAB), em relação à drenagem urbana, uma das temáticas do Plano, o Ministério das Cidades estimula a
utilização de práticas de drenagem urbana que incluem tanto as abordagens com técnicas compensatórias, quanto
as abordagens com princípio do desenvolvimento urbano de baixo impacto. Assim, esta pesquisa teve como
objetivo identificar se o (PLAMSAB) incorpora propostas voltadas para o controle do escoamento na fonte e de
que forma elas são abordadas, o estudo foi conduzido em 3 etapas. Inicialmente foi realizada a análise das
medidas de controle do escoamento pluvial propostas no (PLAMSAB), estudando em que nível são atendidos os
preceitos de medidas de controle do escoamento pluvial junto à fonte (MCF). Posteriormente foi verificada a
viabilidade das MCF para o município, considerando as restrições de cada dispositivo e as particularidades da
ocupação urbana e do grupo hidrológico do solo. Para fornecer subsídio para o dimensionamento futuro das
MCF, foi necessário uma etapa intermediaria de determinação de parâmetros hidrológicos de dimensionamento,
tais como, atualização da relação intensidade-duração-frequência (IDF), determinação do valor da vazão
específica de pré-desenvolvimento (Qpd) e do volume de controle (v). Baseado nas definições de controle da
drenagem na fonte, é possível afirmar que nenhuma das propostas do PLAMSAB para a drenagem urbana,
atende aos preceitos de medidas de controle na fonte, a partir das observações realizadas neste estudo é possível
afirmar, a partir dos dados disponíveis, que grande parte do perímetro urbano do município tem potencial para a
utilização de MCF. As propostas apresentadas no PLAMSAB, em relação a drenagem, consistem na construção
de aproximadamente 631 km de redes de drenagem, além da construção de aproximadamente 180.000 m³ de
depósito anti-DSP, sendo essas distribuídas na cobertura dos 20 anos do horizonte de projeto do Plano. Para a
previsão de implantação da rede de microdrenagem, os autores do PLAMSAB adotaram a vazão de 6,9 m³.s-1,
calculado mediante o método racional, com a utilização dos seguintes parâmetros: Coeficiente de escoamento
(C) = 0,6; Área da bacia (A) = 1,5 km²; Tempo de concentração (tc) = duração da chuva (t) = 1,63 horas; Tempo
de retorno (Tr) = 10 anos; Intensidade de chuva (I) = 27,4 mm.h-1, para a obtenção do valor referente à
intensidade de chuva (I), os autores utilizaram o ajuste de extremo Gumbel dos dados registrados pelo INMET
(Instituto Nacional de Meteorologia). Utilizando a equação IDF atualizada neste estudo, e considerando os
mesmos valores de (t) e (Tr) utilizados no PLAMSAB, resulta um valor de (I) = 42,72 mm.h-1, para esta
intensidade, e para os mesmos valores de (C) e (A), resulta uma vazão de 10,69 m³.s-1, valor 56% maior que a
apresentada no PLAMSAB. A potencialidade do município para implantação de MCF ficou evidenciada a partir
dos resultados deste estudo, o uso de práticas de drenagem em pequena escala, disseminados por toda a bacia
hidrográfica a fim de reproduzir ou manter as condições hidrológicas de pré-desenvolvimento se apresenta como
uma alternativa positiva.
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Monitoramento e modelagem da recarga freática em técnica de drenagem compensatória / Monitoring and modeling of groundwater recharge using a compensatory drainage techniqueSírio, Daniel de Lima Nascimento 23 August 2013 (has links)
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Previous issue date: 2013-08-23 / Financiadora de Estudos e Projetos / Stormwater flooding in urban centers today is the direct result of ground impermeabilization and the ineffective dimensioning of stormwater drainage systems. In order to control these events, innovative low impact stormwater drainage facilities are used in Brazil, which are efficient in controlling sharp peak flows in urban watersheds without, however, affecting the aesthetic appearance of the landscape in these environments. The purpose of this study is to model and estimate the volume of water infiltrated into the soil where a compensatory stormwater drainage system is inserted, which can contribute to groundwater recharge. Modeling was performed by means of a physical storage method and storage variation in soil using a tensiometer, and in digital form using the Hydrus 2D/3D software package. The monitored drainage system and the digitally designed system consist of a water retention basin, a ditch or filter, and an infiltration trench. Groundwater recharge was estimated based on soil analyses, geophysical investigations, flow measurements, and rainfall data, in addition to data collected during 454 days of continuous monitoring of the system by means of tensiometers installed on-site, rain gauges, and the construction of bimodal soil water retention curves using the filter paper method. The moisture content at different depths, the zero water flow plane, and the volumes moving in the soil matrix were calculated based on the identification of the soil water content and matric potential, the hydraulic conductivity in saturated conditions at the monitored depths, and the soil s characteristic curves. The results of the Soil Water Retention Curves (SWRC) and soil moisture content were negligible starting from a depth of 80cm. However, the groundwater recharge rate estimated by the tensiometer method and by the Hydrus digital model was about 45% of the total volume of rainfall. / Atualmente, eventuais problemas de enchentes e inundações, são causas diretas da impermeabilização de áreas nos centros urbanos e do ineficaz dimensionamento da drenagem pluvial nas cidades. No intuito de se controlar estes eventos, equipamentos de drenagem de baixo impacto são inovadoras no Brasil e eficientes no controle de vazões de pico acentuadas em bacias urbanas, sem sobretudo, renunciar à estética e à paisagem nestes ambientes. Neste trabalho objetivou-se modelar e estimar o volume de água infiltrado no solo, onde um sistema de drenagem pluvial compensatória está inserido, que é capaz de contribuir com a recarga freática. A modelagem foi realizada por meio do método de armazenamento e variação da armazenagem no solo com utilização de tensiômetro e de forma digital utilizando-se do software Hydrus 2D/3D. O sistema de drenagem monitorado e o diagramado digitalmente são constituídos de uma bacia de retenção de água, uma vala ou filtro gramado e uma trincheira de infiltração. Na tentativa de estimar a recarga freática realizaram-se, conjuntamente, análises de solo, investigações geofísicas, medidas de vazão, coleta de dados de chuva, além do monitoramento contínuo em 454 dias do sistema através da instalação de tensiômetros no local, pluviógrafos, além da construção de curvas bimodais de retenção de água nos solos por meio do método do papel filtro. A partir da identificação dos potenciais mátricos do solo, da condutividade hidráulica em condições saturadas para as profundidades monitoradas e da obtenção das curvas características do solo, foi possível calcular o teor de umidade em diferentes profundidades, identificar o plano de fluxo zero e calcular os volumes em movimento na matriz do solo. Os resultados obtidos pela verificação das Curvas de Retenção de Água no Solo (CRAs) e umidades de campo foram pouco expressivos a partir de 80cm de profundidade, entretanto, a recarga estimada obtida pelo método dos tensiômetros e pelo modelo digital Hydrus ficou em torno de um valor médio de 45% do volume total precipitado.
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PC-SWMM modeling of policy changes on suburban watersheds in Johnson County, KansasBrady, Grant January 1900 (has links)
Master of Science / Department of Biological & Agricultural Engineering / Stacy Hutchinson / Urban areas have traditionally been managed as separate entities from the natural environment. Recently, urban planners have been interested in reconnecting these areas back to the biosphere to capitalize on ecosystem services restoring damaged hydrologic processes. This study focuses on suburban Johnson County, KS (part of the Greater Kansas City area), which has 62 USEPA 303(d) listed “impaired” or “potentially impaired” waterbodies. Previous studies show that watersheds crisscrossed by multiple politically boundaries see increases in water quantity and decreases in water quality. Using a multi-watershed, multi-city spanning entity like a school district, it is investigated how stormwater best management practices (BMPs) employed over a large entity can help undo the negative effects of watershed political fragmentation.
BMP modeling includes simulating grassroots and planning policy change movements across three target watersheds using PC-SWMM watershed model. The grassroots simulation models rain barrels at single family homes and an extended dry detention basin (EDDB) at schools. Planning policy simulation models 10% and 20% reductions in impervious roads and parking lots in accordance to EPA Smart Growth practices. Resulting, it was seen that all three of these BMPs saw the greatest improvements from current conditions at low precipitation events. Ranking from least to most effective across the outlet’s average flow, maximum flow, and total volume and supporting watershed infiltration, surface runoff, and surface storage are as follows: rain barrels + EDDB, 10% reduced, and 20% reduced impervious simulations. All three stormwater BMPs help demonstrate how grassroots movements and planning polices changes can positively impact regional waterbodies in this maturely suburbanized region.
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Bilan des flux de métaux, carbone organique et nutriments contenus dans une rivière alpine : part des rejets urbains de l'agglomération de Grenoble et apports amont (Isère et Drac) / Balance of Metal, carbon and nutriment flux in a french alpin river : part of urban effluents of Grenoble agglomerationDutordoir, Solène 06 June 2014 (has links)
La prise de conscience grandissante de la contamination des cours d'eau a entraîné l'établissement de réglementations de plus en plus strictes concernant les rejets urbains et la fixation d'objectifs de qualité à atteindre pour les milieux aquatiques. Cependant, l'échantillonnage ponctuel reste une limite importante dans l'estimation des flux de contaminants, et le besoin de suivis en continu est présent dans le milieu naturel et dans les réseaux d'assainissement urbains. Cette étude porte sur la quantification de la part des rejets urbains de l'agglomération grenobloise dans les flux totaux de matières en suspension (MES), nutriments (azote, phosphore), carbone organique et éléments traces métalliques (ETM) du milieu récepteur Isère (une rivière alpine). Ce travail s'est appuyé sur un réseau de mesures en continu de débits (Q) et de MES (par turbidimétrie) à l'amont et à l'aval de l'agglomération et sur une sonde spectrométrique à l'amont, associé à des campagnes de prélèvements réguliers et renforcés pendant les épisodes de crues. Des campagnes de mesures détaillées sur les principaux sous bassins du réseau d'assainissement ont été réalisées durant la période d'étude dans le cadre du schéma directeur d'assainissement de l'agglomération grenobloise. Le croisement de ces deux approches a permis de confronter les variations spatio-temporelles des MES, nutriments, carbone organique et ETM du réseau et du milieu récepteur en 2011 et 2012. Les flux sur ces deux années ont été établis afin de déterminer la contribution des rejets urbains dans les flux du milieu récepteur. La contamination en mercure a fait l'objet d'un suivi particulier du fait de la présence d'une source significative de mercure dans la région. Enfin, une réflexion sur l'amélioration des calculs de flux par l'utilisation de relations entre les ETM/carbone organique particulaire (COP) et un paramètre mesurable en continu (MES, Q) a été menée en parallèle de l'exploitation de ces résultats. Mots-clés : Matières en suspension ; Dynamique des flux ; Nutriments ; Eléments traces métalliques ; Mercure ; Rejets urbains (par temps de pluie et temps sec), sondes de turbidité et spectrométrique. / The growing awareness of the contamination of rivers has led to the establishment of more rigorous regulations related to urban waste, and to the setting of water quality objectives to be achieved for aquatic environment. However, grab sampling remains an important limitation for the estimation of contaminant flux, and the need for constant monitoring is present in both natural environment and urban sanitation. This study focuses on the quantification of the proportion of urban waste in the Grenoble area to the total flux of 1) suspended solids (TSS), 2) nutrients (nitrogen and phosphorus), 3) organic carbon and 4) metals trace element (MTE) of the receiving environment; the Isère (an alpine river). This work was supported by a network of continuous discharge measurements (Q) and TSS (turbidimetry), both upstream and downstream of Grenoble associated with regular sampling campaigns, with a higher measurement frequency during flood events. A spectrometric probe upstream was also placed upstream. Detailed measurement campaigns on major sub-basins of the sewerage network were performed during the study period as part of the sanitation master plan of Grenoble. The combination of these two approaches allowes to relate the spatio-temporal variations of TSS, nutrients, organic carbon and MTE in the urban water network of Grenoble and in the receiving environment (the Isère) for the years 2011 and 2012. Flows of the traced parameters have been established to determine the contribution of urban waste flows in the receiving environment, over these two years. Finally, a study on how to improve the flow calculations by the use of relations between MTE / particulate organic carbon (POC ) and a continuous measurable parameter (MES, Q ) was conducted in parallel with these results. Key words: suspended solids, Nutrients, metals trace element; Mercury; urban waste; turbidimetry and spectrometric probe
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