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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.
91

Desarrollo de un sistema de tratamiento del agua de escorrentía superficial procedente de aparcamientos impermeables usando flujo ascendente y geotextiles

Fernández Barrera, Andrés H. 18 February 2010 (has links)
Esta tesis doctoral presenta la investigación del desarrollo de un prototipo de laboratorio de un sistema de captación, pretratamiento y tratamiento (SCPT) de la escorrentía proveniente de aparcamientos con firmes impermeables. El prototipo de SCPT fue estudiado en condiciones de funcionamiento inicial y a largo plazo. Las respuestas analizadas son las concentraciones de aceites y sólidos en el efluente y las eficiencias de depuración de dichos contaminantes. Finalmente, se analizó la capacidad del sistema de filtrado del SCPT para albergar colonias de microorganismos depuradores de hidrocarburos. Los niveles de depuración alcanzados por el prototipo de SCPT son superiores al 80% para el caso de los sólidos y al 90 % para los aceites, tanto en condiciones de inicio de operación, como a largo plazo tras catorce eventos de lluvia consecutivos. Además, se demostró que el sistema de filtrado es capaz de albergar colonias de microorganismos degradadores de hidrocarburo
92

Naturliga filtermaterial för reduktion av metaller i dagvatten

Skogsfjord, Michael, Blom, Minna January 2006 (has links)
Förorenat dagvatten från Stena Gotthards metallåtervinningsanläggning i Eskilstuna har filtrerats genom kolonner innehållande två olika adsorbenter, torv och furubarksflis. Torv är en organisk jordart som främst används som bränsle och furubarksflis är en biprodukt från skogsindustrin. Båda filtermaterialen är relativt billiga och finns i stora kvantiteter i Sverige. Filtermaterialen har visat sig ha varierande kapacitet att adsorbera metaller i vatten på grund av själva materialet samt vattnets sammansättning. Resultatet från den här studien visar att av de två undersökta filtermaterialen så har furubarksflis störst kapacitet att reducera bly, koppar och zink från det specifika dag vattnet. / Polluted storm water from a metal recycling industry has been filtrated through columns that contained two different adsorbents, peat and pine bark. Peat is an organic soil, mainly used for energy production, and pine bark, a by-product from the forest industry. In Sweden, there are a lot of resources of peat as well as pine bark. Used as filter materials, they are relatively cheep and, like other kinds of filtermaterial used as adsorbents, they have varied capacity to adsorb metals in water. The capacity for the filter materials to adsorb metals depends on the physical structure and chemical contents of the peat and pine bark as well as the water metal composition. Results from this study show that pine bark had the highest adsorption capacity to reduce copper, lead and zinc from the specific storm water.
93

Metodik för beräkning av anslutna hårdgjorda ytor till spillvattennätet / Techniques for calculation of impervious surfaces connected to the sewer system

Larsson, Johan January 2010 (has links)
Sveriges avloppsledningsnät förnyas och utvidgas kontinuerligt. Idag finns ett flertal datorprogram för hydraulisk modellering av flöden och uppdämningsnivåer i spill- och dagvattennät. Modellerna kan även användas som planeringsverktyg för att bedöma effekter av planerade åtgärder samt för uppföljning av utförda åtgärder. Vid uppbyggnaden av en modell krävs beräkningsresultat från en hydrologisk avrinningsmodell som indata. Det största arbetet vid modelluppbyggandet ligger just i beskrivningen av hydrologin. För att kunna simulera avrinningsförlopp i samband med nederbörd på ett verklighetsliknande sätt är kännedom om storleken på och fördelningen av anslutna hårdgjorda ytor till ledningsnätet med snabb nederbördsavrinning väsentligt.    Till kalibreringen och valideringen av avloppsmodellen krävs mätdata. Flödesmätningar är dyra att genomföra vilket har skapat ett intresse att hitta metoder som säkert beräknar de anslutna hårdgjorda ytorna redan från de uppgifter som finns på kartor och i databaser. Svenska riktlinjer för beräkning av hårdgjorda ytor tillhandahålls av branschorganisationen Svenskt Vatten som företräder VA-verken och VA-bolagen i Sverige. Beräkningar med dessa riktlinjer ger dock inte alltid den korrekta storleken på de hårdgjorda ytorna. Syftet med examensarbetet har varit att undersöka olika metoder att beräkna anslutna hårdgjorda ytor till spillvattennätet samt att undersöka huruvida det finns ett samband mellan de avrinningsområden där beräkningarna av de hårdgjorda ytorna inte stämmer. Nio befintliga modeller framtagna i modelleringsverktyget MIKE URBAN användes vid undersökningen. Sex av dessa modeller användes till kalibrering och tre modeller användes till validering.   Undersökningen visade inget samband mellan ytavrinning (reduktionsfaktor) och lutning. Fördelningen av mätpunkter mellan olika jordartskategorier var väldigt ojämn vilket gjorde det svårt att studera huruvida det finns ett samband mellan avrinning och jordart. Resultatet från undersökningen visar att avrinningskoefficienter bör delas upp efter typ av ledningsnät i avrinningsområdet. Metoden med olika avrinningskoefficienter för olika typer av ytor visar på bra resultat för tätbebyggda områden. Metoden med sammanvägda avrinningskoefficienter för olika bebyggelsetyper visar relativt bra resultat med tanke på att det är en överslagsberäkningsmetod.   För tätbebyggda områden bedöms metoden med avrinningskoefficienter för olika typer av ytor fungera bra. Vid mindre tätbebyggda områden ökar osäkerheten. Metoden med sammanvägda avrinningskoefficienter för olika bebyggelsetyper bedöms fungera väl för överslagsberäkningar då den är mindre tidskrävande än den andra metoden. Ingen av de undersökta metoderna bedöms kunna ersätta flödesmätningar. / Sweden’s sewage systems are continuously being maintained and expanded. Several computer programs are today available for hydraulic modeling in sewage and storm water systems. The models can also be used as a planning tool to evaluate effects of planned interventions and to follow up performed interventions. Input data from a runoff model is required at the model build-up. Most of the work in model build-up lies at the description of the hydrology. In order to simulate runoff processes in connection with precipitation, understanding of the size and distribution of impervious surfaces with fast response runoff are essential.   Measurements are required for the calibration and validity check of the model. Unfortunately, flow measurements are expensive to perform. This has created an interest to find methods that safely calculate the connected impervious surfaces already from the information that can be found in maps and in databases. The Swedish guidelines for calculation of impervious surfaces are provided by the Swedish Water and Wastewater Association. Calculations with these guidelines do not always give the true size of the impervious surfaces. The aim of this master thesis was to examine various methods to calculate impervious surfaces connected to the sewage system and whether there is a correlation between drainage areas where the calculations do not agree. Nine existing models developed in the computer program MIKE URBAN were used in this study. Six of these models were used in the calibration and three models were used in the validity check of the methods.   The study did not show any correlation between runoff (reduction factor) and slope. The distribution of datum points between different soil types varied so much that it made it difficult to study whether there was correlation between runoff and soil type. The result from the study showed that the runoff coefficients should be divided after type of sewage system in the drainage area. The method with runoff coefficients for different types of surfaces showed fairly good results for highly urbanized areas. The method with weighted runoff coefficients for different types of habitations showed relatively good results considering that it is a method for rough calculations.   The method with runoff coefficients for different types of surfaces is considered well-functioning for highly urbanized areas. In less urbanized areas, this method showed shorter results. The method with weighted runoff coefficients for different types of habitations is considered well for rough calculations when it is less time consuming than the other method. None of the examined methods are considered able to replace flow measurements.
94

Application of Integrated Watershed Management Modeling on Non-point Source Pollution Evaluation for the Ai-Liao River Basin

Shen, Wei-Lin 23 August 2006 (has links)
In Taiwan, non-point source (NPS) pollution is one of the major causes of the impairment of surface waters. NPS pollutants, which are associated with stormwater runoff from agricultural land uses can be quite diffuse and difficult to treat. The I-Liao Creek Basin, located in southern Taiwan, flows through approximately 90-km and drains towards the Kaoping River. It is one of the major sub-basin in the Kaoping River watershed, which is the largest and the most intensively used watershed in Taiwan. Field investigation results indicate that the main water pollution sources in the I-Liao Creek Basin are domestic wastewater and NPS pollutants from agricultural activities. In this study, an Integrated Watershed Management Model (IWMM) was applied for simulating the water quality in the I-Liao Creek watershed. The model includes a global atmosphere module, a land module, a human impact module, a canopy module, and a global ocean module. Those modules can be linked and managed by a graphic user-interface. The model was calibrated and verified with field data, and was used to investigate potential NPS pollution management plans. Moreover, the Storm Water Management Model (SWMM) was used to verify the accuracy of the simulated results of flow and water qualities. Results from this study show that geographical information system (GIS) is an important mean for land-use identification and waste load estimation in the catchment. Linking the information of land utilization with the NPS pollution simulation model may further provide essential information of pollution potential of NPS pollution for all sub-regions in the river basin. Results and experience obtained from this study will be helpful in designing the watershed management and NPS pollution control strategies for other similar river basins.
95

Pollution transport in the Boden garrison storm water

Udén, Jonathan January 2013 (has links)
In 2012, the Swedish fortification agency started an environmental program for their real estate in northern Sweden. For the Boden garrison this meant an evaluation was needed for their storm water handling. The evaluation fell upon Grontmij AB in Boden. This thesis concerns the pollution from the storm water pipes into its recipient Lule River. Its aim was also to evaluate the areas for the event of a bigger oil spill, since there are many mechanical garages within the garrison. The pollution concerning oil was evaluated by calculating the flow in each outlet into the river, with different rain intensities. For other pollutants, the volumes of storm water each year, for every outlet were calculated. With concern for the snow melting process, it was also calculated for which period of the year would be interesting to keep an extra watch for pollutant concentrations and maximum flows. Results showed that for a 50-year period, none of the years would have had their peak flow because of the snow melt. The results for evaluation of an oil spill showed that none of the outlets were equipped for an accident of such sort, should it coincide with a rainfall of a high intensity. The results also showed that one of the outlets had an oil trap only dimensioned for rainfall of the lowest intensity. The calculating of pollutant volumes raises the concern for reliable data, but measures have already been taken to meet this concern.
96

Uppföljning av reningsfunktionen i Steningedalens våtmark / Follow-Up of the Water Purification Function at Wetland of Steningedalen

Girleviciute, Aiste January 2018 (has links)
Dagvattnet från Märsta är belastat med bland annat tungmetaller och näringsämnen. Vattnet hamnar i Märstaån och transporteras vidare ut till Mälaren. Steningedalens våtmark är ett dammsystem som renar och fördröjer en del av Märstaåns flöde före transport ut mot Mälaren.   Syftet med detta självständiga arbete på kandidatnivå har varit att undersöka anläggningens reningsfunktion med hjälp av sedimentprovtagning. Sedimentprover har tagits vid in- och utloppet och en kemisk analys av dessa har utförts i ett ackrediterat laboratorium. Resultaten från in- och utloppet har jämförts för att se om det sker en minskning av föroreningar genom systemet. Fem sedimentfällor har placerats ut i delar av dammsystemet för att undersöka sedimentfördelningen och muddringsbehovet i anläggningen. Resultatet av studien visade att dammsystemet har en god vattenreningsfunktion med avseende på tungmetallerna bly, nickel, kadmium, krom, koppar och zink samt näringsämnet fosfor. Anläggningen har bedömts att vara i behov av muddring. / In Märsta, the storm water is contaminated with heavy metals and nutrients (nitrogen and phosphorus) among other pollutants. The water emits to the river Märstaån and further to the lake Mälaren. The wetland of Steningedalen is a pond system that delays part of the stream in Märstaån and purifies the water on its way through the system. This independent project is based on investigation of the purification functioning at Steningedalen wetland. The investigation has been done by sediment sampling and analysis. The samples were taken from the inlet and the outlet of the pond system. Chemical analysis has been made on these samples in an accredited laboratory. The results were compared in order to see if there is a trend through the system. Five sediment traps were placed in parts of the system to study the distribution of the sediment and the need of dredging. The results of the study have concluded that the stormwater pond system has a good water purification function with regard to heavy metals lead, nickel, cadmium, chromium, copper and and zinc aswell as the nutrient phosphorous. The study has also shown that the system is in need of dredging.
97

Avaliação de elementos de infiltração de águas pluviais na zona norte da cidade de Goiânia / Evaluation of evidence of infiltration of rainwater in the northern city of Goiania

CARVALHO, Eufrosina Terezinha Leão 29 August 2009 (has links)
Made available in DSpace on 2014-07-29T15:18:25Z (GMT). No. of bitstreams: 1 Iniciais.pdf: 371351 bytes, checksum: 472ce466492930efb99bf7d39356b637 (MD5) Previous issue date: 2009-08-29 / The development of the urban environment results in an expansion of impervious ground surfaces that greatly affects the hydrological cycle in the cities. The objective of this research is to evaluate infiltration structures for the control of excess drainage at the origin of runoff. These structures are constructed with the purpose of minimizing the impact of impervious surfaces to the urban environment. An experimental field was established consisting of several infiltration structures, such as small-diameter pilot wells and real scale wells. The real scale wells used perforated concrete pipe casing and brick lining. Falling-head infiltration tests were carried out during 15 months, encompassing the dry and rainy seasons. The infiltration tests were undertaken with initial conditions that correspond to the natural water content at the time of testing. Additional tests were undertaken with previously flooded conditions, reproducing several consecutive rainy days. The monitoring of pilot wells along with real scale wells allowed the evaluation of project parameters obtained from pilot wells. The values of average infiltration rate of different infiltration wells were compared and the performance of the several structures was compared. Laboratory test were carried out for the determination of the hydraulic parameters of the ground profile, including the saturated hydraulic conductivity the soil-water characteristic curve. A numerical model for the simulation of infiltration wells was implemented using the software FlexPDE. Special boundary conditions were developed that take into account the transient relationship between the varying hydraulic head at the well walls and the total volume infiltrated during a test. The numerical simulations contributed for a better understanding of the infiltration mechanism, the influence of the hydraulic conductivity to the infiltration rate, and the determination of the wetting front and pore-water pressures during infiltration. A design criterion for infiltration wells was proposed using daily compensation, considering the daily water balance during 25 years, and the precipitation historical series of the site. The proposed design criterion makes possible the selection of the group of infiltration structures that meet the project goals. The design criterion also allowed the evaluation of the theoretical performance of wells designed using two conventional criteria / A expansão do ambiente urbano causa o aumento das superfícies impermeabilizadas, alterando o ciclo hidrológico nas cidades. Esta pesquisa buscou avaliar estruturas de infiltração para o controle de fluxos superficiais na fonte, construídas com a finalidade de minimizar os impactos da impermeabilização nas cidades. Foi estabelecido um campo experimental composto por diversas estruturas de infiltração, incluindo poços piloto de pequeno diâmetro e poços em escala real. Os poços em escala real foram revestidos em tubo de concreto perfurado e em tijolo maciço assentado em crivo. Ensaios de infiltração com carga variável foram realizados durante 15 meses, abrangendo as estações seca e chuvosa. Os ensaios de infiltração foram realizados em condição inicial de umidade natural e em condição pré-inundada, procurando reproduzir vários dias consecutivos de chuva. O monitoramento dos poços piloto, juntamente com estruturas de infiltração em escala real, permitiu a avaliação dos parâmetros de projetos obtidos a partir dos poços piloto. Os valores de taxa de infiltração média foram comparados entre os diferentes elementos de infiltração e permitiram comparar o desempenho das estruturas. Foram realizados ensaios de laboratório para obtenção de parâmetros hidráulicos do perfil de solo do campo experimental. Dentre as propriedades avaliadas destacam-se a permeabilidade do solo saturado e a curva característica. Um modelo numérico foi implementado utilizando o programa FlexPDE. Foram desenvolvidas condições de fronteira especiais que consideram a dependência transiente entre a carga hidráulica nas paredes do poço e o volume total infiltrado durante o ensaio. A simulação numérica permitiu o melhor entendimento do mecanismo de infiltração, a influência da permeabilidade na taxa de infiltração e a determinação da frente de saturação e da distribuição de poro-pressão durante a infiltração. Foi proposto um critério de dimensionamento de poços de infiltração através da compensação diária, analisando todos os dias durante 25 anos e utilizando a série histórica de chuvas da região. Esse critério permite selecionar e dimensionar a estrutura ou um grupo de estruturas que melhor atenda ao projeto. O critério proposto permitiu também avaliar o desempenho teórico de sistemas dimensionados utilizando dois critérios convencionais
98

Avaliação de elementos de infiltração de águas pluviais na zona norte da cidade de Goiânia / Evaluation of evidence of infiltration of rainwater in the northern city of Goiania

Carvalho, Eufrosina Terezinha Leão 29 August 2008 (has links)
Submitted by Cássia Santos (cassia.bcufg@gmail.com) on 2016-07-13T10:45:16Z No. of bitstreams: 2 Dissertação - Eufrosina Terezinha Leão Carvalho - 2008.pdf: 13164722 bytes, checksum: 0c1d7d328573ca1eeb1ecda67f236ff6 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Rejected by Luciana Ferreira (lucgeral@gmail.com), reason: on 2016-07-13T10:47:46Z (GMT) / Submitted by Cássia Santos (cassia.bcufg@gmail.com) on 2016-07-13T10:50:39Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação - Eufrosina Terezinha Leão Carvalho - 2008.pdf: 13164722 bytes, checksum: 0c1d7d328573ca1eeb1ecda67f236ff6 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-07-13T12:39:12Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação - Eufrosina Terezinha Leão Carvalho - 2008.pdf: 13164722 bytes, checksum: 0c1d7d328573ca1eeb1ecda67f236ff6 (MD5) / Made available in DSpace on 2016-07-13T12:39:12Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação - Eufrosina Terezinha Leão Carvalho - 2008.pdf: 13164722 bytes, checksum: 0c1d7d328573ca1eeb1ecda67f236ff6 (MD5) Previous issue date: 2008-08-29 / The development of the urban environment results in an expansion of impervious ground surfaces that greatly affects the hydrological cycle in the cities. The objective of this research is to evaluate infiltration structures for the control of excess drainage at the origin of runoff. These structures are constructed with the purpose of minimizing the impact of impervious surfaces to the urban environment. An experimental field was established consisting of several infiltration structures, such as small-diameter pilot wells and real scale wells. The real scale wells used perforated concrete pipe casing and brick lining. Falling-head infiltration tests were carried out during 15 months, encompassing the dry and rainy seasons. The infiltration tests were undertaken with initial conditions that correspond to the natural water content at the time of testing. Additional tests were undertaken with previously flooded conditions, reproducing several consecutive rainy days. The monitoring of pilot wells along with real scale wells allowed the evaluation of project parameters obtained from pilot wells. The values of average infiltration rate of different infiltration wells were compared and the performance of the several structures was compared. Laboratory test were carried out for the determination of the hydraulic parameters of the ground profile, including the saturated hydraulic conductivity the soil-water characteristic curve. A numerical model for the simulation of infiltration wells was implemented using the software FlexPDE. Special boundary conditions were developed that take into account the transient relationship between the varying hydraulic head at the well walls and the total volume infiltrated during a test. The numerical simulations contributed for a better understanding of the infiltration mechanism, the influence of the hydraulic conductivity to the infiltration rate, and the determination of the wetting front and pore-water pressures during infiltration. A design criterion for infiltration wells was proposed using daily compensation, considering the daily water balance during 25 years, and the precipitation historical series of the site. The proposed design criterion makes possible the selection of the group of infiltration structures that meet the project goals. The design criterion also allowed the evaluation of the theoretical performance of wells designed using two conventional criteria / A expansão do ambiente urbano causa o aumento das superfícies impermeabilizadas, alterando o ciclo hidrológico nas cidades. Esta pesquisa buscou avaliar estruturas de infiltração para o controle de fluxos superficiais na fonte, construídas com a finalidade de minimizar os impactos da impermeabilização nas cidades. Foi estabelecido um campo experimental composto por diversas estruturas de infiltração, incluindo poços piloto de pequeno diâmetro e poços em escala real. Os poços em escala real foram revestidos em tubo de concreto perfurado e em tijolo maciço assentado em crivo. Ensaios de infiltração com carga variável foram realizados durante 15 meses, abrangendo as estações seca e chuvosa. Os ensaios de infiltração foram realizados em condição inicial de umidade natural e em condição pré-inundada, procurando reproduzir vários dias consecutivos de chuva. O monitoramento dos poços piloto, juntamente com estruturas de infiltração em escala real, permitiu a avaliação dos parâmetros de projetos obtidos a partir dos poços piloto. Os valores de taxa de infiltração média foram comparados entre os diferentes elementos de infiltração e permitiram comparar o desempenho das estruturas. Foram realizados ensaios de laboratório para obtenção de parâmetros hidráulicos do perfil de solo do campo experimental. Dentre as propriedades avaliadas destacam-se a permeabilidade do solo saturado e a curva característica. Um modelo numérico foi implementado utilizando o programa FlexPDE. Foram desenvolvidas condições de fronteira especiais que consideram a dependência transiente entre a carga hidráulica nas paredes do poço e o volume total infiltrado durante o ensaio. A simulação numérica permitiu o melhor entendimento do mecanismo de infiltração, a influência da permeabilidade na taxa de infiltração e a determinação da frente de saturação e da distribuição de poro-pressão durante a infiltração. Foi proposto um critério de dimensionamento de poços de infiltração através da compensação diária, analisando todos os dias durante 25 anos e utilizando a série histórica de chuvas da região. Esse critério permite selecionar e dimensionar a estrutura ou um grupo de estruturas que melhor atenda ao projeto. O critério proposto permitiu também avaliar o desempenho teórico de sistemas dimensionados utilizando dois critérios convencionais
99

Komplexní hospodaření s vodou v objektu rodinného domu bez možnosti napojení na kanalizační síť / Comprehensive water management in a family house without connection to the wastewater disposal system

Plhák, Jiří January 2016 (has links)
Czech Republic is called roof of the Europe, several rivers rise here and many of them flow away and continue to other countries. That's why I find, that’s extremely important to manage out water sources properly and carefully, because for example the weather has a huge impact on our limited sources and can affect them especially in a dry periods. These issues can be improved by finding a use for used water, good storm water management as well as using greywater. In my diploma thesis, I'll be mainly focused on an overall water management in an ordinary family house. It has two parts as theoretical part and practical part. The theoretical part is then split into another three parts. The first part covers a storm water management, the second is about waste water management. The third explains greywater management. In practical part of my diploma thesis, there's my study of not disposing rain water into a drain with other waste water, but making both waters useful. In this my particular subject in village called Plesnice, is projected a waste water treatment plant. Treated water will be accumulate together with rain water. Accumulated water will be used for irrigation. For a waste water treatment is projected a constructed wetland with vertical flow (down flow reed beds) and facility for sludge management. This is example of extensive technology. Irrigation system consists of storage tank with mechanical pre-treatment and pump valve shaft, sprinklers for lawns, drip irrigation decorative surfaces and everything is controlled by a control unit. Thanks to irrigation and rainwater remains in effect, which is important for local microclimate and save drinking water. This study is an example of that in water management is not necessarily a need for global action, but you can start with individuals and individual houses, which in total could have a significant effect on water retention in the landscape and to slow down and reduce the peak flow in rivers.
100

Fördröjning av dagvatten / Delaying of Storm Water

Hagelin, Robert, Mbanzabugabo, Steve January 2015 (has links)
Den ökade mängden hårdgjorda ytor i städerna skapar en större och snabbare avrinning av dagvatten till ledningsnäten. En del av dagens befintliga ledningar klarar inte av att hantera denna ökade mängd dagvatten. En snabb och kortsiktig lösning på lösa detta problem är att anlägga fördröjningsmagasin som avlastar ledningsnäten. Fram till denna tidpunkt har det inte utförs tillräckligt med undersökningar kring de olika effekter som placeringen av ett fördröjningsmagasin medför. Ett fördröjningsmagasin som anläggs för att fördröja flödet av dagvatten från ett delområde kan, vid felplacering, ha en negativ verkan på flödet längre ner i ledningsnätet. Denna flödesreglering kan vara till nackdel för ledningsnätet eftersom det fördröjda flödet från delområdet kan samverka med flödestoppen från en annan del av området och kan skapa översvämningar. Syftet med denna rapport var att undersöka om olika placeringar av ett fördröjningsmagasin hade någon effekt på flödet i ett dagvattensystem. Målet var att finna placeringar där ett fördröjningsmagasin förhindrade en samverkan av flödestoppar och minskade antalet översvämningarna i ledningsnätet. Arbetet utfördes genom hydraulisk modellering i programmet MIKE URBAN. I programmet undersöktes två olika modeller över dagvattensystem. Resultaten ur de två modellerna visar på att placeringen av magasin i ett dagvattensystem har betydelse för hur översvämningar kan undvikas. Lägst antal översvämningar uppstod när magasinen placerades i viktiga knutpunkter på ledningsnätet. Mer tid och resurser bör läggas ner på att undersöka effekten av fördröjningsmagasinets position och dimension innan de placeras ut i dagvattensystemet. På detta sätt kan både kostnader minskas och framtida problem undvikas. / The increased amount of impermeable surfaces in the cities creates a larger and faster runoff of rainwater into the drainage systems. Some of today's existing pipelines are not able to handle this increased amount of storm water. A quick and short term solution to solve this problem is to construct delaying reservoirs that unburden the drainage system. Up to this point, not enough studies have been conducted on the different effects that a placement of a reservoir brings to a drainage system. If incorrectly positioned, a reservoir built for delaying the flow of storm water from a section of a drainage system can, have a negative effect on the flow further down the system. This flow regulation can be harmful to the system when the delayed flow from the section can interact with the flood peak from another section and can cause flooding. The purpose of this report was to study if different placements of a reservoir had any effect on the flow in a storm water drainage system. The aim was to find places where a reservoir could be positioned to prevent the collaboration of peak flows.  This thesis was mainly conducted with the use of the hydraulic modeling program MIKE URBAN in which studies of two models are the bases of the results presented in this report. The results from the two models show that the placement of a reservoir in a drainage system has a large sway on how to avoid flooding. The least amount of floods was attained when the reservoir was placed in certain key positions in the drainage system. More time and resources should be devoted to further investigate the effect of a reservoir’s position and dimensions before being placed into a drainage system. This way, expenditures could be reduced and simultaneously future flooding avoided.

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