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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.
251

Problematika perfluorovaných sloučenin ve složkách životního prostředí / Issues of perfluorinated compounds in the environmental compartments

Kalášek, Stanislav January 2008 (has links)
Perfluoroalkylated substencies are priority organics polutants. They are evolved to the environment from many sources. We classify them as new xenobiotics which are present in the environment. There will be described their chemical, physical and environmental properties in theoretical part and there will be described the analytical chemistry of these substancies in varios types of environmental samples. There will be developed metod for their identification and quantification. For this assignment will be use especially chromathografic methods. There will be developed standard operation procedure. The procedure will be verify on real environmental samples.
252

Využití plynové chromatografie pro stanovení reziduí léčiv ve vodách / Aplication of gas chromatography for determination of drug residuals in waters

Lacina, Petr January 2009 (has links)
Diploma thesis is focused on the choose of methods and optimalisation analysis procedure of selected pharmaceuticals (salicylic acid, ibuprofene, naproxene, ketoprofene and diclofenac) in surface and waste water by using gas chromatography with mass spectrometer (GC-MS). Solid-phase extraction (SPE) with Oasis HLB cartridges was used as an extraction method in this analysis. Extraction is followed by derivatization and their optimalization of selected pharmaceuticals. Derivatization and its optimalization were performed by two silylation reagens N-methyl-N-(trimethylsilyl)trifluoroacetamide (MSTFA) and N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA). Different volumes of derivatization reagents, different temperatures and different times were used during the procedure. The best combination is then used for analysis of real samples. Real samples of waste water were collected in sewage treatment plants in Brno – Modřice and real samples of surface water were collected from several rivers and one pond in region Moravia. This thesis also presents and tests SPE methods for extraction and concentration selected sulfonamide residues (sulfamethazine, sulfamethoxazole, sulfapyridine and sulfathiazole) from the aquatic environment.
253

Upravitelnost povrchových vod / Treatibility of surface water

Fuks, Josef January 2013 (has links)
The aim of the master´s thesis is the topic of the treatability of surface water with the focus on the process of suspension formation. For this work I took water samples from five different places around the Brno Dam which has contended with water quality deterioration for a long period. With these water samples, the series of jar coagulation tests were done with the application of three different commonly used coagulants. In the theoretical part of the master´s thesis I deal with the composition and attributes of surface water and the technology of its treatment. Each process of treatment is briefly described here with the emphasis on the process of suspension formation. The experimental part of the master´s thesis summarizes and presents the results gained through the coagulation tests in the laboratory. I evaluate the influence of different parameters on final effectiveness of water treatment and I try to find an optimal amount of coagulant, pH and speed of fast or slow mixing. Finally I compare the suitability of each coagulant and the influence of the sampling site on the effectiveness of water treatment.
254

Nekonvenční technologie obrábění vodním paprskem / The unconventional Technology of Cutting Water Jet

Šimíček, Václav January 2010 (has links)
This diploma thesis deals with the unconventional technology of cutting water jet. The aim of this thesis is analysis of technological possibilities of water jet, possible operating modes (techniques) and entering technological data and influence of technical parameters on quality and accuracy of cutting. The thesis contains several experiment at which was examined achieved quality and accuracy of cuts, and simultaneously there is solved technoeconomic evaluation of this technology.
255

Studium degradace léčiv s využitím pokročilých oxidačních procesů / Study of Pharmaceuticals Degradationby Advanced Oxidation Processes

Bílková, Zuzana January 2015 (has links)
At present, the issue of occurrence of female sex hormones, estrogens and progestogens, in aquatic ecosystems is often discussed by experts and the general public. These substances of steroid structure can be difficult to remove completely by conventional wastewater and drinking water treatment technologies. In given context advanced oxidation processes based on in situ generation of highly reactive hydroxyl radicals can be a suitable technique. This thesis deals with the study of kinetics and degradation products of photocatalytic decomposition of seven female sex hormones (estrone, -estradiol, estriol, ethinylestradiol, diethylstilbestrol, progesterone and norethindrone). Experiments were conducted in a laboratory glass reactor, which was equipped with an energy efficient UV-A LED light source (365 nm emission wavelength) and an immobilised photocatalyst in a form of TiO2 five-layer film deposited on glass. Model samples of water with the initial hormone concentration of 1 mg·L-1 were used and the degradation process was monitored by an HPLC-MS method. In the given system all compounds of interest except estriol had very significant tendency to be adsorb. In the case of estriol the formal rate constant of photocatalytic decomposition was determined based on the Langmuir-Hinshelwood model for two different initial concentrations, 0.5527 hour-1 (1 mg·L-1) and 0.1929 hour-1 (5 mg·L-1), and by comparison of these values it was found that the higher degraded compound concentration, the slower decomposition (fivefold increase of the initial concentration resulted in the constant decrease to almost one-third). Moreover nine degradation products of estriol photocatalytic decomposition were recorded and their structure was designed based on mass spectra. In the second thematic part of the thesis attention was paid to development of a SPE-HPLC-MS method for simultaneous determination of female sex hormones in water ecosystems, with emphasis on an extraction part optimization. The final samples treatment process included besides extraction with Supel™ Select HLB 200 mg SPE cartridges also mechanical impurities removal, hormones extraction from solids trapped on filtration material, sample acidification and extract purification with Supelclean™ ENVI-Florisil® cartridges. Optimised method was used for determination of female sex hormones in two Brno rivers, Svitava and Svratka. In the most cases the concentration was below the detection or quantification limit.
256

Determination of anions and cations in natural water

Netshifhefhe, Humbelani Kelly 21 September 2018 (has links)
MSc (Chemistry) / Department of Chemistry / Surface water is used for domestic and agricultural activities in Musina region and other surrounding areas. This is because of the shortage of potable water. As a result, the people living in the region and its surrounding areas are potentially exposed to hazardous contaminants that may be present in the surface water. It is therefore important to ascertain the quality of the surface water in the region. Surface water samples were collected from Mutale, Nwanedi, Tshipise and Nzhelele rivers. The samples were analysed for anions such as fluoride (F-), chloride (Cl-), nitrate (NO3-), phosphate (PO43-), sulphate (SO42-); cations such as aluminium (Al), calcium (Ca), iron (Fe), potassium (K), magnesium (Mg), sodium (Na) and trace metals such as lithium (Li), vanadium (V), chromium (Cr), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), molybdenum (Mo), cadmium (Cd), thallium (Tl) and lead (Pb) by using analytical techniques such as IC, ICP-OES and ICP-MS. The same samples were also investigated for other parameters such as pH, temperature, EC, TH, TDS, Na % and SAR. The WHO (2008), SANS 241 (2006) and Canadian guideline (2017) were used as a water quality guideline for drinking purposes. Higher concentrations of Li, V, Cr, Ni, Cu, Zn, Al, Ca, Mg, K and Na in river water were detected in rainy season, whereas higher concentrations of As, Mo, K and Fe were recorded in dry season. The concentration of F-, Cd, Tl and Pb showed low contamination level in river samples. The results demonstrated that Tshipise river water was contaminated with high concentration of parameters: TDS (1864.0.8-3372.8 mg L-1), EC (2960.3-5270 mS cm-1), F- (6.403-8.419 mg L-1), SO42- (289.657-326.598 mg L-1), Na (836.690-922.810 mg L-1) and As (10.017-11.267 μg L-1) and relative to the (WHO) water guidelines. Nwanedi river also showed higher values of EC (298.0-699.0) mS cm-1 and TDS (190.3-447.5) mg L-1. In this study, the results indicated that water from Tshipise and Nwanedi river is not suitable for human consumption based on the guidelines of drinking water. The results also indicated that the soil sample had abundance of Ca, Al, Mn and Fe with concentration ranging from 0.13-10595, 0.0084-4.16, 0.0455-1116.5, 2.4-287404 mg Kg-1 respectively. / NRF
257

Investigation of a polyether trisiloxane surfactant: Environmental fate and homologue specific trace analysis from surface water

Michel, Amandine 28 July 2015 (has links)
Thanks to their adaptability and high efficiency compared to traditional carbon based surfactants, silicone surfactants are a success in many different applications, from pesticides to cosmetics, polyurethane foam, textile and car care products. In spite of those numerous applications, no analytical method existed for their trace determination in environmental samples and no data have been available regarding their environmental occurrence and fate. An analytical method for the trace analysis of trisiloxane surfactants in the aqueous environment was developed and validated. The method, based on liquid-liquid extraction and HPLC-MS/MS, reaches limits of quantification in the ng L-1 range and allows an individual quantification of every homologue of the targeted trisiloxane surfactant. The newly developed analytical method was applied to analyze 40 river water samples. The targeted trisiloxane surfactant was detected in 14 samples, between 1 ng L-1 and 100 ng L-1. The results showed that the studied trisiloxane surfactant does not ubiquitously occur in the aquatic environment in measurable concentrations, but can reach surface waters on a local scale. In order to assess the persistence of the trisiloxane surfactant in surface waters, its hydrolysis was studied in the lab, under various conditions (temperature, pH, and concentration). The half-lifes at pH 7 and 2 mg L-1 were found to be between 29 days and 55 days at 25°C and between 151 days and 289 days at 12°C. Taking only into account the hydrolysis, these results indicate that the trisiloxane surfactant could persist several weeks in surface waters. A degradation product of the trisiloxane surfactant was tentatively identified by high resolution mass spectrometry. When used as agricultural adjuvants, trisiloxane surfactants may reach the soil compartment and might further leach to ground water. The behavior of the trisiloxane surfactant on soil was therefore investigated to assess the possibility to reach ground water. With a sorption batch equilibrium method, distribution coefficients between water and soil (Kd, Koc, and Kclay) were estimated for two standard soils (loam and sandy loam) and for every homologue of the trisiloxane surfactant. The obtained values for Kd were between 15 L kg-1 and 135 L kg-1, indicating that the trisiloxane surfactant is only slightly mobile in soil. To further investigate the possibility of leaching to ground water after application on agricultural fields, the leaching in soil was simulated in the lab in a soil column. The experimental settings were designed to simulate a worst case scenario where the application of the trisiloxane surfactant is done on quartz sand and is immediately followed by a heavy rainfall. Even in these conditions, less than 0.01 % of the initially applied trisiloxane surfactant leached through 20 cm of quartz sand. Based on the Kd values and the results of the leaching in soil column, the studied trisiloxane surfactant is considered to be unlikely to leach to ground water after application as an agricultural adjuvant.
258

Vattenbrist i Blekinge län : En kvalitativ studie kring allmänhetens kunskap och medvetenhet kring yt-och grundvattenbrist / Water scarcity in Blekinge county : A qualitative study of the public's knowledge and awareness of surface and groundwater scarcity

Nilsson, Michaela January 2020 (has links)
Vatten är grunden för allt liv på jorden och en livsviktig resurs för både människor, djur och växtlighet. Trots det tenderar människor att se vatten som en oändlig resurs och tar tillgången på rent dricksvatten för givet. I Sverige används både grundvatten samt ytvatten från vattendrag och sjöar till dricksvatten. Tillgången på sötvatten påverkas av förändringar i klimatet och under de senaste åren har somrarna i de södra delarna av Sverige varit ovanligt torra och varma samtidigt som det har fallit mindre nederbörd än vad som är normalt. Detta har tidvis medfört en osäkerhet kring tillgången på dricksvatten. Syftet med studien som gjordes var att kartlägga allmänhetens kunskap och medvetenhet kring yt-och grundvattenbrist i framförallt de östra delarna av Blekinge län och undersöka ifall denna uppfattning stämde överens med ansvariga offentliga verksamheters strategi och information kring vattenbrist. I studien genomfördes två intervjuer med ansvariga verksamheter för vattenförvaltning i Blekinge län samt en allmän enkätundersökning som metod för att kartlägga allmänhetens kunskap kring vattenbrist. Utifrån resultaten från enkätundersökningen kunde det konstateras att den allmänna medvetenheten kring vattenbrist i Blekinge län generellt sett var god och att utgångspunkten för att människor skulle vara beredda att förändra sina dagliga vanemönster såg relativt hoppfull ut. Däremot framgick det att majoriteten av de respondenter som svarade på enkätundersökningen skulle önska mer information från ansvariga offentliga verksamheter gällande vattenbrist och tydligare riktlinjer för hur man kan gå tillväga för att hushålla med dricksvatten. / Water is the basis of all life on Earth and a vital resource for humans, animals and plants. Despite this, the public tends to see water as an endless resource and many people often take the supply of drinking water for granted. The access of fresh water is affected by climate change and in the last couple of years, the summers in the southernmost parts of Sweden have been unusually dry and warm and meanwhile there has been less precipitation than usual. This has occasionally led to an uncertainty regarding access to drinking water. The purpose of the study was to estimate the awareness of the public regarding surface and groundwater scarcity, particularly in the eastern parts of Blekinge county, and to examine if this awareness overlapped with public authorities' strategies and information about water scarcity. The study consisted of two interviews with responsible water management authorities in Blekinge and a general survey as a means to clarify the public's knowledge about water scarcity. Based on the results of the survey it was determined that the general awareness of water scarcity in Blekinge is generally good. Furthermore, the outlook for changed behaviour among the public on daily habit basis look promising. However, the majority of the respondents in the survey would wish for more information from responsible public authorities regarding water scarcity and more distinct guidelines on how to save drinking water.
259

Advanced techniques for solving groundwater and surface water problems in the context of inverse methods and climate change.

Todaro, Valeria 17 May 2021 (has links)
[ES] El tema de la investigación se centra en técnicas avanzadas para manejar problemas de aguas subterráneas y superficiales relacionados con métodos inversos y cambio climático. Los filtros de Kalman, con especial atención en Ensemble Smoother with Multiple Data Assimilation (ES-MDA), se analizan y mejoran para la solución de diferentes tipos de problemas inversos. En particular, la principal novedad es la aplicación de estos métodos para la identificación de series temporales. La primera parte de la tesis, luego de la descripción del método, presenta el desarrollo de un software escrito en Python para la aplicación de la metodología propuesta. El software cuenta con un flujo de trabajo flexible que puede adaptarse fácilmente para implementar diferentes variantes del filtro de Kalman y ser aplicado para la solución de varios tipos de problemas. Un paquete de herramientas proporciona varias funcionalidades que permiten de configurar el algoritmo de acuerdo con el problema específico analizado. La primera aplicación se refiere a la solución del problema inverso de flujo en ríos. Este es un procedimiento inverso destinado a estimar el flujo de entrada a un sistema hidráulico en función de información recopilada abajo. El procedimiento se prueba mediante dos ejemplos sintéticos y un estudio de caso real; se investiga el impacto de los tamaños de los conjuntos y la aplicación de técnicas de localización e inflación de covarianzas. Los resultados muestran la capacidad del método propuesto de resolver este tipo de problemas; el rendimiento de ES-MDA mejora, especialmente para tamaños de conjuntos pequeños, cuando se aplican técnicas de inflación y localización de covarianza. La segunda aplicación en el campo de las aguas superficiales se refiere a la calibración de un modelo hidrológico-hidráulico que simula los mecanismos de formación de eventos de inundación. ES-MDA se acopla al modelo numérico de forma paralela para la estimación de los coeficientes de rugosidad e infiltración en base al conocimiento de un hidrograma de flujo en una sección del dominio. Los resultados de dos casos sintéticos y un estudio de caso real demuestran la capacidad del método propuesto para calibrar el modelo hidrológico-hidráulico con un tiempo computacional razonable. En el campo de aguas subterráneas, ES-MDA se aplica por primera vez para identificar simultáneamente la ubicación de la fuente y el historial de liberación de un contaminante en un acuífero a partir de datos de concentración detectados en diferentes puntos del dominio. Se realizaron numerosas pruebas para evaluar la influencia de la distribución espacial y temporal de los datos de concentración, el número del conjunto y el uso de técnicas de localización e inflación; además, se presenta un nuevo procedimiento para realizar una localización iterativa espacio-temporal. La metodología se valida mediante un ejemplo analítico y un estudio de caso que utiliza datos obtenidos en el laboratorio mediante una caja de arena. ES-MDA conduce a una buena estimación de los parámetros investigados; una red de monitoreo bien diseñada y la aplicación de correcciones de covarianza mejoran el rendimiento del método y ayudan a mitigar el posible problema de no unicidad de la solución. Otro propósito de la tesis es investigar el efecto del cambio climático en las aguas subterráneas. Se presenta un modelo simplificado que describe la respuesta de los niveles de agua subterránea a las variables meteorológicas hasta 2100. Es un enfoque estadístico sencillo basado en las correlaciones entre los niveles de agua subterránea y dos índices de sequía que dependen de los datos de precipitación y temperatura. El método se utiliza para evaluar el impacto del cambio climático en los recursos de agua subterránea en un área de estudio ubicada en el norte de Italia utilizando datos históricos y de modelos climáticos regionales. Los resultados m / [CA] El tema de la investigació se centra en tècniques avançades per a manejar problemes d'aigües subterrànies i superficials relacionats amb mètodes inversos i canvi climàtic. Els filtres de Kalman, amb especial atenció en Ensemble Smoother with Multiple Data Assimilation (ES-MDA), s'analitzen i milloren per a la solució de diferents tipus de problemes inversos. En particular, la principal novetat és l'aplicació d'aquests mètodes per a la identificació de sèries temporals. La primera part de la tesi presenta el desenvolupament d'un programari escrit en Python per l'aplicació de la metodologia presentada. El programari compta amb un flux de treball flexible que pot adaptar-se fàcilment per a implementar diferents variants del filtre de Kalman i ser aplicat per a la solució de diversos tipus de problemes. Un paquet complementar d'eines proporciona diverses funcionalitats que permeten de configurar l'algorisme d'acord amb el problema específic analitzat. La primera aplicació es un nou enfocament per la solució del problema invers de flux en rius. Aquest és un procediment invers destinat a estimar el flux d'entrada a un sistema hidràulic en funció d'informació recopilada aigües avall. El procediment es prova mitjançant dos exemples sintètics i un estudi de cas real; s'investiga l'impacte de les grandàries dels conjunts i l'aplicació de tècniques de localització i inflació de covariàncies. Els resultats mostren la capacitat del mètode proposat de resoldre aquest tipus de problemes; el rendiment de ES-MDA millora, especialment per a grandàries de conjunts xicotets, quan s'apliquen tècniques d'inflació i localització de covariància. La segona aplicació en el camp de les aigües superficials es refereix al calibratge d'un model hidrològic-hidràulic que simula els mecanismes de formació d'esdeveniments d'inundació a partir de sollicitació hidrometeorológicas i la seua posterior propagació. ES-MDA s'acobla al model numèric de manera paral·lela per l'estimació dels coeficients de rugositat i infiltració sobre la base del coneixement d'un hidrograma de flux en una secció del domini. Els resultats de dos casos sintètics i un estudi de cas real demostren la capacitat del mètode proposat per calibrar el model hidrològic-hidràulic amb un temps computacional raonable. En el camp d'aigües subterrànies, ES-MDA s'aplica per primera vegada per identificar simultàniament la ubicació de la font i l'historial d'alliberament d'un contaminant en un aqüífer a partir d'un conjunt de dades de concentració detectats en diferents punts del domini. Es van realitzar nombroses proves per avaluar la influència de la distribució espacial i temporal de les dades de concentració, el número del conjunt i l'ús de tècniques de localització i inflació; a més, es presenta un nou procediment per realitzar una localització iterativa espaciotemporal. La metodologia es valguda mitjançant un exemple analític i un estudi de cas per al qual s'utilitzen dades obtingudes en el laboratori mitjançant una caixa d'arena. ES-MDA condueix a una bona reconstrucció dels paràmetres investigats; una xarxa de monitoratge ben dissenyada i l'aplicació de correccions de covariància milloren el rendiment del mètode i ajuden a mitigar el possible problema de no unicitat de la solució. Un altre propòsit de la tesi és investigar l'efecte del canvi climàtic en les aigües subterrànies. Es presenta un model simplificat que descriu la resposta dels nivells d'aigua subterrània a les variables meteorològiques fins a 2100. És un enfocament estadístic senzill basat en les correlacions entre els nivells d'aigua subterrània i dos índexs de sequera que depenen de les dades de precipitació i temperatura. El mètode s'utilitza per a avaluar l'impacte del canvi climàtic en els recursos d'aigua subterrània en una àrea d'estudi situada en el nord d'Itàlia utilitzant dades històriques i de models climàtics regionals. / [EN] This work focuses on the investigation of advanced techniques to handle groundwater and surface water problems in the framework of inverse methods and climate change. The Ensemble Kalman filter methods, with particular attention to the Ensemble Smoother with Multiple Data Assimilation (ES-MDA), are extensively analyzed and improved for the solution of different types of inverse problems. In particular, the main novelty is the application of these methods for the identification of time series function. In the first part of the thesis, after the description of the ES-MDA method, the development of a Python software package for the application of the proposed methodology is presented. It is designed with a flexible workflow that can be easily adapted to implement different variants of the Ensemble Kalman filter and to be applied for the solution of various types of inverse problems. A complemented tool package provides several functionalities that allow to setup the algorithm configuration suiting the specific analyzed problem. The first novelty application of the ES-MDA method aimed at solving the reverse flow routing problem. The objective of the inverse procedure is the estimation of an unknown inflow hydrograph to a hydraulic system on the basis of information collected downstream and a given forward routing model that relates inflow hydrograph and downstream observations. The procedure is tested by means of two synthetic examples and a real case study; the impact of ensemble sizes and the application of covariance localization and inflation techniques are also investigated. The tests show the capability of the proposed method to solve this type of problem; the performance of ES-MDA improves, especially for small ensemble sizes, when covariance localization and inflation techniques are applied. The second application, in the context of surface water, concerns the calibration of a hydrological-hydraulic model that simulates rainfall-runoff processes. The ES-MDA is coupled with the numerical model by parallel way for the estimation of roughness and infiltration coefficients based on the knowledge of a discharge hydrograph at the basin outlet. The results of two synthetic tests and a real case study demonstrate the capability of the proposed method to calibrate the hydrological-hydraulic model with a reasonable computational time. In the groundwater field, ES-MDA is applied for the first time to simultaneously identify the source location and the release history of a contaminant spill in an aquifer from a sparse set of concentration data collected in few points of the aquifer. The impacts of the concentration sampling scheme, the ensemble size and the use of covariance localization and covariance inflation techniques are tested; furthermore, a new procedure to perform a spatiotemporal iterative localization is presented. The methodology is tested by means of an analytical example and a study case that uses real data collected in a laboratory sandbox. ES-MDA leads to a good estimation of the investigated parameters; a well-designed monitoring network and the use of covariance corrections improve the performance of the method and help to minimize ill-posedness and equifinality. A part of the thesis investigates the impact of climate change on the groundwater availability. A surrogate model that describes the response of groundwater levels to meteorological variables up to 2100 is presented. It is a simple statistical approach based on the correlations between groundwater levels and two drought indices that depend on precipitation and temperature data. The presented method is used to evaluate the impact of climate change on groundwater resources in a study area located in Northern Italy using historical and regional climate model data. The results denote a progressive increase of groundwater droughts in the investigated area. / Todaro, V. (2021). Advanced techniques for solving groundwater and surface water problems in the context of inverse methods and climate change [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/166439 / TESIS
260

Undersökning av en teknisk lösning för att minska risken för översvämning i lågstråk i en urban miljö vid större nederbörd / Investigation of a Technical Solution to Reduce the Risk of Flooding in Low-lying Areas in an Urban Environment During Heavy Rainfall

Olsenius, Björn, Tornell, Mattias January 2021 (has links)
Syfte: I många städer finns områden som ligger lägre än omgivande terräng (lågstråk). I dessa lågstråk finns det stor risk att dagvatten ansamlas vid skyfall och medför över-svämningar och skador på byggnader och anläggningar. I denna studie har det genom-förts en undersökning av olika teorier, metoder och tillämpningar som kan ligga till grund för en teknisk lösning för att lösa problematiken med översvämningsrisken i en urban miljö (dvs stadsmiljö) med lågstråk. Metod: Först genomfördes en litteraturstudie i syfte att bland annat fördjupa kunskapen om ämnet. Därefter gjordes fyra intervjuer där målet var att tillgodogöra den kunskap som sakkunniga har om bland annat vilka tekniska lösningar som är lämpliga i urban miljö och vilka kostnader som olika dagvattenanläggningar har. Det sista steget var att utföra en fallstudie i Växjö stad där en utvald lösning studerades med målet att under-söka lämpligheten i att anlägga just den lösningen. Resultat: Av intervjuerna framgick det att det är många parametrar att ta hänsyn till när man ska projektera och bygga dagvattenanläggningar som är effektiva vid skyfall. Öppna lösningar såsom översvämningsytor och diken/kanaler föredrogs då de dels var mer effektiva, dels att de oftast var billigare att konstruera. Även litteraturstudien gav liknande resultat men det var större variation på vilka lösningar som var lämpliga. Fall-studien visade att den föreslagna lösningen kunde svälja upp till 60% av nederbörden vid ett 30-årsregn men endast i värsta fall 16% av ett 100-årsregn. Konsekvenser: Av resultatet att döma var den föreslagna lösningen inte tillräcklig för att lösa översvämningsproblematiken vid ett 100-årsregn, vilket var den återkomsttid som Växjö kommun har störst problem vid. För att hantera den stora nederbördsmäng-den måste det till mycket stora magasinsvolymer eller många små lösningar för att en accepterad nivå kan uppnås, vilket den lösning som testades inte klarade av. I intervju-erna framgick detta också att det ofta var detta som var problemet vilket i grunden beror på för liten tillgänglig yta och för mycket hårdgjord yta. Rekommendationen blir att komplettera med flera andra lösningar alternativt anlägga så kallade kassetter under gatan för att öka magasineringskapaciteten. Begränsningar: Resultatet begränsas av att det är platsspecifikt och därmed svårare att applicera på andra platser. Eftersom det har genomförts intervjuer på flera olika kom-muner så har dock denna aspekt minskat något eftersom många olika åsikter har note-rats och presenterats. De beräkningar som utfördes var inte genom en datamodellering vilket möjligtvis kan påverka tillförlitligheten något även om det enligt litteraturen an-sågs hålla en tillräcklig nivå för att kunna användas på mindre arealer. / Purpose: In many cities there are areas that are lower than the surrounding terrain (low-lying areas). In these low-lying areas, there is a great risk that stormwater will accumu-late in the event of heavy rainfall and cause floods and damage to buildings and facili-ties. In this study, a review has been carried out of various theories, methods and appli-cations that can form the basis for a technical solution to solve the problem of flood risk in an urban environment with low-lying areas. Method: First, a literature study was conducted to, among other things, deepen the knowledge of the subject. Subsequently, four interviews were conducted where the goal was to utilize the knowledge that experts have about which technical solutions are suit-able in an urban environment and what costs different stormwater facilities have. The last step was to carry out a case study where a selected solution was studied with the aim of investigating the suitability of constructing that solution. Findings: The interviews showed that there are many parameters to take into account when designing and building stormwater facilities that are effective in the event of a downpour. Open solutions such as flood surfaces and ditches / canals were preferred as they were partly more efficient and partly because they were often cheaper to construct. The literature study also gave similar results, but there was greater variation in which solutions were suitable. The case study showed that the proposed solution could swal-low up to 60% of the precipitation in a 30-year rain but in the worst case only 16% of a 100-year rain. Implications: Judging by the results, the proposed solution was not sufficient to solve the flood problem in the event of a 100-year rain, which was the return time that Växjö municipality has the biggest problem with. To handle the large amount of precipitation, very large magazine volumes or many small solutions are needed in order for an ac-cepted level to be achieved, which the solution that was tested could not achieve. In the interviews, it also emerged that this was often the problem, which is basically due to too little available space and too much hardened surface. The recommendation will be to supplement with several other solutions or to install so-called cassettes under the street to increase storage capacity. Limitations: The result is limited by the fact that it is site-specific and thus more diffi-cult to apply in other locations. Since interviews have been conducted in several differ-ent municipalities, however, this aspect has diminished somewhat as many different opinions have been noted and presented. The calculations performed were not through a data modelling, which could possibly affect the reliability somewhat, even though according to the literature it was considered to maintain a sufficient level to be able to be used on smaller areas.

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