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Implantação de reservatórios de detenção em conjuntos habitacionais: a experiência da CDHU. / Implementation of stormwater storage facilities for low income dwelling: the CDHU experiences.Nakazone, Lucia Midori 12 January 2006 (has links)
Novas medidas de controle das vazões excedentes surgiram nos últimos anos e buscam contornar as mudanças nos ciclos hidrológicos, imitando e mantendo as condições naturais existentes antes dos processos de urbanização. Uma dessas alternativas, conhecida genericamente pelo nome de reservatório de armazenamento, procura reter parte do escoamento superficial gerado durante as precipitações, para depois fazer sua devolução de forma lenta e gradual aos leitos dos córregos e rios, atenuando o pico dos hidrogramas e redistribuindo as vazões ao longo do tempo. Uma das variáveis desse reservatório de armazenamento, que permanece seco entre eventos chuvosos, é denominado de reservatório de detenção e constitui-se o objeto deste trabalho. Sua implantação e utilização são discutidas por meio das experiências da CDHU, através de estudos de casos reais, onde prova-se que a incorporação desse novo dispositivo de drenagem urbana é ainda um assunto polêmico, para o qual técnicos, governantes e população estão despreparados. É legítimo o anseio da sociedade por medidas sustentáveis e ambientalmente corretas, na qual os reservatórios de detenção se enquadram, porém sua implementação por força de medidas legais, muitas vezes, tem sido realizada de forma pouco conseqüente, sem planejamento e ponderação quanto às dificuldades e implicações dessa atitude. Denota-se também, a necessidade de avaliação da eficiência destes dispositivos e de normatização das formas de aplicação, dimensionamento, operação e manutenção. Além disso, é necessário a sensibilização, a conscientização e a educação em todos os níveis, pois existem paradigmas a serem quebrados e obstáculos a serem vencidos. Ao final do trabalho, sugere-se um pequeno roteiro com diretrizes gerais para incorporação dos reservatórios de detenção em novos empreendimentos, com o intuito de orientar e facilitar a utilização desses dispositivos, melhorando sua aceitação pela sociedade. / New stormwater control techniques have emerged during last years, trying to mimic and keep the natural conditions of hydrologic cycle. One of these measures, known as storage facility, detains part of the rainfall runoff to release it at controlled rates downstream, attenuating the hydrograph peak and redistributing the volume over a certain period of time. The focus of this report is the detention basin, a storage facility designed to empty out between runoff occurrences. Its insertion and use are discussed through CDHU experiences, based on real cases, where the results show that this new urban drainage control system is still a polemic issue, for what technicians, governments and population are unprepared. Societys concerns about sustainable and environmentally correct measures, inside which detention pond is placed, are rightful, however its implementation in the course of legal procedures has been made carelessly, unplanned and without considerations of difficulties and impacts. In addition, evaluation of its performance along with regulation of using forms, dimensioning, operation and maintenance are also required. Moreover, sensitiveness, consciousness and education related to detention basin should be improved, since there are paradigms to be broken and obstacles to win. At the end of this report, it is suggested some guidelines to incorporate detention basins in new land development, not only to facilitate and instruct the use of this structure, but also to improve societys acceptance.
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Implantação de reservatórios de detenção em conjuntos habitacionais: a experiência da CDHU. / Implementation of stormwater storage facilities for low income dwelling: the CDHU experiences.Lucia Midori Nakazone 12 January 2006 (has links)
Novas medidas de controle das vazões excedentes surgiram nos últimos anos e buscam contornar as mudanças nos ciclos hidrológicos, imitando e mantendo as condições naturais existentes antes dos processos de urbanização. Uma dessas alternativas, conhecida genericamente pelo nome de reservatório de armazenamento, procura reter parte do escoamento superficial gerado durante as precipitações, para depois fazer sua devolução de forma lenta e gradual aos leitos dos córregos e rios, atenuando o pico dos hidrogramas e redistribuindo as vazões ao longo do tempo. Uma das variáveis desse reservatório de armazenamento, que permanece seco entre eventos chuvosos, é denominado de reservatório de detenção e constitui-se o objeto deste trabalho. Sua implantação e utilização são discutidas por meio das experiências da CDHU, através de estudos de casos reais, onde prova-se que a incorporação desse novo dispositivo de drenagem urbana é ainda um assunto polêmico, para o qual técnicos, governantes e população estão despreparados. É legítimo o anseio da sociedade por medidas sustentáveis e ambientalmente corretas, na qual os reservatórios de detenção se enquadram, porém sua implementação por força de medidas legais, muitas vezes, tem sido realizada de forma pouco conseqüente, sem planejamento e ponderação quanto às dificuldades e implicações dessa atitude. Denota-se também, a necessidade de avaliação da eficiência destes dispositivos e de normatização das formas de aplicação, dimensionamento, operação e manutenção. Além disso, é necessário a sensibilização, a conscientização e a educação em todos os níveis, pois existem paradigmas a serem quebrados e obstáculos a serem vencidos. Ao final do trabalho, sugere-se um pequeno roteiro com diretrizes gerais para incorporação dos reservatórios de detenção em novos empreendimentos, com o intuito de orientar e facilitar a utilização desses dispositivos, melhorando sua aceitação pela sociedade. / New stormwater control techniques have emerged during last years, trying to mimic and keep the natural conditions of hydrologic cycle. One of these measures, known as storage facility, detains part of the rainfall runoff to release it at controlled rates downstream, attenuating the hydrograph peak and redistributing the volume over a certain period of time. The focus of this report is the detention basin, a storage facility designed to empty out between runoff occurrences. Its insertion and use are discussed through CDHU experiences, based on real cases, where the results show that this new urban drainage control system is still a polemic issue, for what technicians, governments and population are unprepared. Societys concerns about sustainable and environmentally correct measures, inside which detention pond is placed, are rightful, however its implementation in the course of legal procedures has been made carelessly, unplanned and without considerations of difficulties and impacts. In addition, evaluation of its performance along with regulation of using forms, dimensioning, operation and maintenance are also required. Moreover, sensitiveness, consciousness and education related to detention basin should be improved, since there are paradigms to be broken and obstacles to win. At the end of this report, it is suggested some guidelines to incorporate detention basins in new land development, not only to facilitate and instruct the use of this structure, but also to improve societys acceptance.
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Effects of Anthropogenic Nutrient Enrichment on Exotic and Restored Native Aquatic VegetationParnell, Allison 2011 May 1900 (has links)
Understanding how nutrient input into coastal wetlands influences aquatic vegetation and the fate of anthropogenic nutrient inputs can help improve water quality management plans. The goals of this study were to (1) compare nutrient concentrations in various storage compartments downstream from two point nutrient sources (a sewage treatment plant outfall and a residential detention basin) in Armand Bayou, a coastal brackish wetland in the Galveston Bay (Texas, USA) watershed, and (2) determine if nutrient storage in those compartments helped improve water quality downstream.
Water column nutrients can be assimilated by aquatic vegetation, adsorbed to sediment, or diluted within the system as distance from source input increases. To determine the fate of nutrients to Armand Bayou, I measured nutrient concentrations in the sediment, water column, pore water, and tissue of exotic and restored native plants downstream from a sewage treatment plant and a residential detention basin. To assess nutrient removal potential of a common exotic species, I determined relative growth and nutrient uptake rates of Eichhornia crassipes. Water column total nitrogen, NH₄⁺ and NO₃ˉ concentrations decreased by 95, 96 and 99 percent downstream from the sewage outfall (~2200 m distance). Water column NH₄⁺ and NO₂ˉ concentrations decreased by 93 and 75 percent downstream from the detention basin (~2500 m distance). Exotic species Alternanthera philoxeroides, Pistia stratiotes and E. crassipes showed higher aboveground/emergent tissue nutrient content than restored, native Schoenoplectus californicus for both tributaries. Schoenoplectus californicus had the largest biomass although appeared to be limited in its ability to remove nitrogen from the water column. Nutrient uptake rates by E. crassipes were low and did not change with increasing distance from nutrient source, but high relative growth rates in both tributaries suggest the nuisance potential of this exotic species. Low sediment and pore water nutrient concentrations for both tributaries suggest these compartments are not sinks. All plant species did not respond to changes in water column nutrient concentrations with increasing distance from source input suggesting dilution to be the main factor in water column nutrient decline for both tributaries.
This study will provide water quality resource managers guidance on the development of total maximum daily loads (TMDLs) for water bodies impaired by high nutrient loading and the implementation of wetland plants efficient in nutrient removal for water quality improvement.
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A Study On Flood Management Practices For GuzelyurtSahin, Erdal 01 August 2012 (has links) (PDF)
This study deals with the investigation of characteristics of a flash flood and development of design of flood mitigation facilities occurred in Gü / zelyurt in North Cyprus on 18th of January, 2010 and development of design of flood mitigation facilities. Hydrologic and hydraulic modeling of this flood event has been utilized to develop solutions for preventing the region from the flood. Topographical maps and soil properties are used in hydrological modeling. The data are inserted into a geographical information system program (ARC-GIS) where basin properties are obtained. Since there is no any stream flow gauging station along the creeks in the study area, the synthetic unit hydrograph is developed by using Soil Conversation Service Method to obtain design flood hydrographs. In hydraulic modeling, the cross-section data of Fabrika Creek and Bostanci Creek are taken by using global navigation satellite system (GNSS) device and total station. These data are entered into the HEC-RAS program. Flood inundation maps are generated for both creeks. After hydrological and hydraulic modeling, two solutions are proposed. The first one is to build a detention basin for storing water and a lateral channel.
for diverting extra flow from Bostanci Creek to Fabrika Creek. The second solution is to build a lateral channel from Bostanci Creek to Gü / zelyurt Dam for diverting all water during a flood event. Based on hydrologic, hydraulic, and cost analysis, the first solution is accepted to be the feasible solution. In addition, flow carrying capacities of the creeks are improved.
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Bassin de retenue des eaux pluviales en milieu urbain : performance en matière de piégeage des micropolluants / Urban stormwater detention basin : performance in terms of micropollutant trappingSebastian, Christel 27 November 2013 (has links)
Les bassins de retenue des eaux pluviales constituent des éléments importants de gestion des rejets urbains de temps de pluie (RUTP). De nombreuses études montrent que, lorsqu’ils sont bien conçus, ils permettent de lutter contre les inondations et de décanter efficacement la pollution métallique et les hydrocarbures fortement fixés aux matières en suspension (MES). Le travail se propose d’étudier les performances de ce type de système afin d’en mesurer et d’en modéliser leur efficacité en termes d’abattement de micropolluants à une échelle évènementielle. Pour cela, il a été développé un suivi expérimental d’un bassin en service sec et étanche de grande taille localisé à l’exutoire d’un bassin versant drainé par un réseau d’assainissement séparatif pluvial faisant partie de l’Observatoire de Terrain en Hydrologie Urbaine (OTHU). Ainsi un total de 100 micropolluants (MP) a–t-il été suivi : 22 éléments traces métalliques (ETM), 16 hydrocarbures aromatiques polycycliques (HAP), 2 alkylphénols (AP), 5 alkylphénols éthoxylates (APEO), Bisphénol A, 9 polybromodiphényléthers (PBDE) et 45 pesticides. Dans les eaux, ils ont été analysés en phase dissoute et particulaire en entrée et en sortie. 67 % des MP recherchés ont été détectés au moins une fois en entrée ou en sortie. Les concentrations moyennes évènementielles à l’exutoire du bassin versant alimentant l’ouvrage sont comparables aux données de la littérature quand elles existent et montrent une grande variabilité. L’efficacité massique évènementielle (EME) de piégeage des MP a été évaluée selon différentes méthodes, prenant en compte les incertitudes totales. L’efficacité est avérée pour la majorité des ETM et HAP, sur un nombre limité de campagnes pour les PBDE et les APEO, très limité pour le 4-Tert-Octylphénol et le 4-Nonyphénol (1 sur 5). Les performances de l’ouvrage ont été mises en avant pour 7 pesticides (sur 15 détectés) mais des efficacités négatives témoignent d’un relargage possible des polluants. L’étude des sédiments accumulés dans le bassin depuis 6 ans montre qu’ils sont assez chargés tant en métaux, HAPs qu’en 4-Nonylphénol, BDE209 et Diuron. Enfin, nous avons expérimenté 3 niveaux de modèles afin d’identifier des pistes pertinentes pour la suite des travaux dans ce domaine. / Detention basins are at stake in urban stormwater discharges (USWD) management strategies. If well designed, they are not only used to mitigate stormwater flood impacts but also to trap metals and hydrocarbon compounds strongly bounded to total suspended solids (TSS). An experimental monitoring, in the framework the Field Observatory on Urban Hydrology (OTHU), was developed on a large dry detention basin located at the outlet of a catchment drained by a separate stormwater system. This basin presents a rather classical and current configuration.A sum of 100 substances was studied: 22 metals (ETM), 16 polycyclic aromatic hydrocarbons (PAH), 2 alkylphenols (AP), 5 ethoxylate alkylphenols (APEO), Bisphénol A, 9 polybromodiphenylethers (PBDE) and 45 pesticides. They were analyzed in both dissolved and particulate phases in water at the inlet and outlet of the device. 67% of MP studied was detected at least once at the inlet or outlet. Event mean concentrations were in the same range as literature data when available and showed an important variability.Event mass efficiency (EME) in trapping MP was assessed by different methods taking account for global uncertainties. Acceptable efficiency was found for most of ETM and PAH and in a lesser extent for PBDE and APEO on a limited number of campaign. The detention basin had only a positive impact on alkylphenols (4-Tert-Octylphenol and 4-Nonylphenol) for one campaign out 5. Negative values for 7 pesticides (among 15 detected) indicated possible pollutant release. Accumulated sediments study showed high MP concentrations in particular for metals, PAH, 4-Nonylphenol, BDE209 and Diuron. Lastly, different levels of models were tested to try to identify relevant ones for further work.
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Expérimentations et modélisations tridimensionnelles de l’hydrodynamique, du transport particulaire, de la décantation et de la remise en suspension en régime transitoire dans un bassin de retenue d’eaux pluviales urbaines / Experiments and 3D modelling of hydrodynamics, sediment transport, settling and resuspension under unsteady conditions in an urban stormwater detention basinYan, Hexiang 28 May 2013 (has links)
Les bassins de retenue des eaux pluviales sont utilisés pour préserver la qualité des eaux réceptrices par sédimentation pendant le temps de pluie. Cependant, les efficacités du bassins n'étaient pas satisfaisants en raison de la mal compréhension du processus de sédimentation. Afin de mieux comprendre ces processus dans des ouvrages in situ, cette thèse porte à la fois sur des expérimentations in situ et sur les modélisations de l'hydrodynamique et du transport particulaire dans les bassins de retenue pilotes et in situ. Cette recherche s’est appuyée en grande partie sur le bassin Django Reinhardt (BDR) à Chassieu (volume: 32000 m3, surface: 11000 m2) dans le cadre de l’OTHU et sur les données expérimentales obtenues par Dufresne (2008) et Vosswinkel et al. (2012). Les échantillons de sédiments ont été prélevés et leurs caractéristiques physiques ont été analysées en laboratoire dans le but de cerner leur distribution spatiale. Concernant la modélisation numérique, les simulations de l’hydrodynamique en régime permanent ont été réalisées à l'aide du logiciel CFD Fluent et ont été évaluées à partir de l’analyse de corrélation entre le comportement hydrodynamique du bassin et la distribution spatiale des caractéristiques physiques des sédiments. Les conditions limites sur le fond couramment utilisées et largement décrites dans la littérature ont été testées dans le but de représenter la distribution spatiale des sédiments et l’efficacité de décantation du BDR. Les conditions testées sont : i) contrainte de cisaillement critique ou bed shear stress – BSS et ii) énergie cinétique turbulente critique ou bed turbulent kinetic energy - BTKE. L’approche Euler-Lagrange dite « particle tracking » a été mise en œuvre. En raison de l'échec de prédiction des zones de dépôt à l’aide des conditions limites disponibles (BSS et BTKE), une nouvelle relation a été proposée pour estimer le seuil BTKE. La condition à la limite obtenue en utilisant cette nouvelle relation a été testée sur un bassin pilote (Dufresne, 2008) et sur le BDR en régime permanent. Les résultats obtenus n’étaient pas très satisfaisants concernant la prédiction des zones de dépôt et l’efficacité de décantation dans le bassin BDR, même en considérant une distribution granulométrique non uniforme. Afin de mieux prédire les zones de dépôt dans le BDR, une nouvelle méthode a été proposée en considérant le transport des particules, leur décantation et leur érosion en régime transitoire. Sur la base de la méthode proposée pour le transport des particules, la décantation et l'érosion en régime transitoire, plusieurs modélisations avec différentes conditions limites ont été réalisées dans un bassin de retenue pilote rectangulaire (Vosswinkel et al., 2012). Les prédictions des efficacités et des zones de dépôt en régime transitoire avec la méthode proposée sont satisfaisantes / Stormwater detention basins are used to preserve the quality of receiving waters by sedimentation during the wet weather. However, the removal efficiencies of basin were not satisfactory due to the not well understanding of the sedimentation processes. In order to further understand these processes in the real facilities, this thesis therefore focuses both on in situ experiments and modeling of the hydrodynamic and sediment transport in field detention basin and in small scale basin in laboratory. This research was supported by large part on the Django Reinhardt basin (DRB) in Chassieu within the OTHU program and the experimental data deriving from Dufresne (2008) and Vosswinkel et al. (2012). Samples of sediments accumulated in the basin were collected and their physical characteristics were analyzed in order to determine their spatial distribution. Concerning numerical modeling, the hydrodynamic simulations in steady state were performed using CFD software Fluent and were evaluated by the correlation analysis between the hydrodynamic behavior of DRB and the spatial distribution of the physical characteristics of sediments. The bed boundary conditions used in the literatures were tested in order to represent the spatial distribution of sediments and removal efficiency of DRB. The conditions tested were: i) critical bed shear stress - BSS and ii) critical bed turbulent kinetic energy - BTKE. Because of the failure prediction of DRB deposit zones with usual bed boundary conditions, a new relationship based on particle settling velocities has been proposed to estimate the BTKE threshold for the bed boundary condition. The proposed boundary condition was tested in a pilot basin (Dufresne, 2008) and the DRB using the Euler-Lagrange approach under steady flow conditions. The results were not very satisfactory regarding the DRB deposit zones, even considering non-uniform grain size. In order to better predict the deposit zones and settling efficiency in field detention basins, a new method has been proposed accounting for the sediment transport, settling and erosion under unsteady conditions. Based on this proposed method for representing the particle transport, settling and erosion processes under unsteady conditions, various simulations with different bed boundary conditions were carried out in a pilot rectangular basin (Vosswinkel et al., 2012). The predictions of removal efficiencies and deposition zones are satisfactory. Hence, taking into account transient effects on both hydrodynamics and sediment transport leads to drastically improve the spatial and temporal distributions of sediments in settling detention basins.
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Opatření pro zvýšení transformační schopnosti inundačního území Svitavy v úseku Holásky – Chrlice / Measures to increase the transformation capacity of the Svitava inundation area in the Holásky - Chrlice sectionHavran, David Unknown Date (has links)
This diploma thesis deals with the possibilities of using the left inundation area of Svitava river for purposes of transformation of the 100-years flood wave in Svitava. The area of interest is located on the territory of the Holásky and Chrlice city districts. SMS software with a hydraulic two-dimensional simulation model SRH was used to simulate the flow in the current state and variant solutions of the proposed state. Based on the results of the flow in the current state, two variant solutions of the proposed state were designed and simulated. The result of this work is the quantification of the change in the transformation capabilities of the area of interest in both proposed variants and followed by a recommendation.
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Enhancing Urban Flood Resilience: A pilot case study of a GIS Suitability Mapping framework for NBS placement in SwedenBatuigas, Kristin, Petrovic, Aleksandra January 2024 (has links)
The escalating impact of climate change has become a significant global concern, particularly in urban environments through the risk of flooding, due to intensified precipitation patterns. Nature Based Solu-tions (NBS), offer effective strategies for mitigating flood risks by enhancing stormwater management and promoting urban resilience. Multicriteria Analysis (MCA) has shown to be useful for identifying suitable areas for NBS, however, there is limited research on its application specifically for urban flood resilience in Sweden. Therefore, this study aims to develop a GIS-based suitability mapping framework within MCA method for allocating suitable areas for two NBS measures: Retention Pond (RP) and Detention Basin (DB), applying it to a case study in Sweden. The study employs a mixed-method approach and consists of (1) framework develop-ment through a literature review, geospatial data assessment, and key-informant interviews, and (2) application of the framework to a case study area in Sweden. In the case study area, the resulting suitability map indicates that 7.5 % of DBs and 7% of RPs met all criteria. Key-informant interviews with local experts provided valuable insights, particularly the exclusion of hazardous zones as well as emphasizing the importance of considering not only biophysical characteristics, but also socio-cultural factors. In conclusion, this study contributes to the body of knowledge on NBS suitability mapping. The findings offer guidance to climate strategists and urban planners on a municipal level, selecting optimal locations for NBS strategies for urban flood resilience and stormwater management.
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