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  • 1.
    Abrahamsson, Sandra
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology.
    Utformning av mjukvarusensorer för avloppsvatten med multivariata analysmetoder2013Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Studies of real processes are based on measured data. In the past, the amount of available data was very limited. However, with modern technology, the information which is possible to obtain from measurements is more available, which considerably alters the possibility to understand and describe processes. Multivariate analysis is often used when large datasets which contains many variables are evaluated.

    In this thesis, the multivariate analysis methods PCA (principal component analysis) and PLS (partial least squares projection to latent structures) has been applied to wastewater data collected at Hammarby Sjöstadsverk WWTP (wastewater treatment plant).

    Wastewater treatment plants are required to monitor and control their systems in order to reduce their environmental impact. With improved knowledge of the processes involved, the impact can be significantly decreased without affecting the plant efficiency. Several variables are easy to measure directly in the water, while other require extensive laboratory analysis. Some of the parameters from the latter category are the contents of phosphorus and nitrogen in the water, both of which are important for the wastewater treatment results. The concentrations of these substances in the inlet water vary during the day and are difficult to monitor properly.

    The purpose of this study was to investigate whether it is possible, from the more easily measured variables, to obtain information on those which require more extensive analysis. This was done by using multivariate analysis to create models attempting to explain the variation in these variables. The models are commonly referred to as soft sensors, since they don’t actually make use of any physical sensors to measure the relevant variable.

    Data were collected during the period of March 11 to March 15, 2013 in the wastewater at different stages of the treatment process and a number of multivariate models were created. The result shows that it is possible to obtain information about the variables with PLS models based on easy-to-measure variables. The best created model was the one explaining the concentration of nitrogen in the inlet water.

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  • 2.
    Adolfsson Lindahl, Frida
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Identifiering av skyfallskänsliga punkter till Västerås kommunsvattentjänstplan: Risk- och sårbarhetsanalys samt lågpunktskartering2023Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    As of January 1st, 2024, all municipalities must have a water service plan. A water service plan must contain each municipality's long-term plan to provide public water services in the future and solutions that need to be taken in the event of a cloudburst to protect water and sewage facilities. The change in law was introduced on January 1st, 2023, which has given municipalities a tight timetable to develop this plan.

    The study has investigated what the water service plan in Västerås municipality needs to contain in order to fulfill the requirement for solutions in the event of cloudbursts, identify points in the waste and stormwater network that are potentially vulnerable to cloudbursts, and provide suggestions for torrential rain measures. In order to fulfill the purpose, a risk and vulnerability analysis has been carried out to identify points in the waste and stormwater network that are potentially vulnerable to cloudbursts. The analysis included a workshop, with key individuals at Mälarenergi Vatten AB, and a risk matrix that was used as an assessment basis. From the risk matrix, points that were potentially vulnerable to cloudbursts were identified and a low-point mapping was performed in SCALGO Live at the selected points. The rain events performed in the mapping were 10-, 20- and 100-year rainfalls. The low-point mapping was compared with a cloudburst mapping with land runoff and conduit network, which is a mapping with a high degree of detail, to investigate whether low-point mapping can be a suitable basis for a water service plan.

    The result of the risk and vulnerability analysis was that seven points, which were given as suggestions during the workshop, had high-risk values and were potentially vulnerable to cloudbursts. Three out of the seven points were selected for further analysis: Branthovda, Skiljebo, and Önsta-Gryta, all of them located in Västerås city. All of these sensitive points were in the stormwater network. The low-point mapping in SCALGO Live performed over these three points showed major flooding during a 100-year rainfall event. The proposed cloudburst solutions for the sites were storage areas and cloudburst roads. When comparing low-point mapping and cloudburst mapping with ground runoff and conduit networks, the cloudburst mapping showed a minor flood for Branthovda and Skiljebo. In Önsta-Gryta, the difference between the mappings was minimal. This was due to the results of the cloudburst mapping showing that the stormwater pipes in the area were overloaded even with a 10-year rain, which was similar to the condition in the low-point mapping that the stormwater pipes are assumed to be filled. With this, only a low point mapping can show an area's potential for being vulnerable to cloudbursts but does not say anything about how the waste or stormwater network is affected. However, low point mapping can help identify areas in built-up areas that could be vulnerable to flooding.

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  • 3.
    Adolfsson Lindahl, Frida
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Edholm, Sigrid
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Hagberg, Felicia
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Holmgren, Niclas
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Källbom, Jacob
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Magnusson, Astrid
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Våtmarkers potential att rena avloppsvatten från läkemedelsrester2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Denna studie genomfördes på uppdrag av det statliga forskningsinstitutet Formas. Syftet med rapporten var att undersöka hur effektiva våtmarker är som tilläggsrening av avloppsvatten, detta med avseende på reducering av läkemedel samt skadeeffekter på akvatiska organismer. Rapporten baserades på en tidigare studie utförd av Breitholtz et al. (2012) där mätningar av läkemedelshalter samt mortalitet och larvutveckling hos hoppkräftor, Nitocra spinipes, gjordes i fyra olika våtmarker.  De fyra våtmarkerna ligger i Eskilstuna, Oxelösund, Nynäshamn och Trosa. Deras mätningar undersökte mortalitet och larvutvecklingskvot för hoppkräftor i prover utspädda med bräckt vatten vid koncentration avloppsvatten på, 11,25 %; 22,5 %; 45% och 90 %. Proverna för läkemedelshalter späddes inte ut och enbart ett mätvärde per våtmark togs vid inflödet och utflödet.

    I denna rapport undersöktes dessa frågeställningar: (1) Är anlagda våtmarker som tilläggsrening en effektiv metod med avseende på skadeeffekter hos hoppkräftor, (2) till vilken grad reduceras halten läkemedel när våtmarker används som tilläggsrening samt (3) finns det ett samband mellan läkemedelsrester och hoppkräftornas överlevnad?

    För att besvara de tre frågeställningarna genomfördes en metaanalys av data från studien av Breitholtz et al. (2012). Hoppkräftors mortalitet, larvutvecklingskvot (LDR) och koncentration av läkemedel analyserades. Endast mortalitet och larvutvecklingskvot hade tillräckligt med data för utförande av en metaanalys. Läkemedelsanalysen kunde bara göras på en grundläggande nivå.

    Metaanalysen programmerades i MATLAB R2019b, där skillnaden i medelvärdet för mortalitet respektive larvutvecklingskvot beräknades mellan in- och utflöde för de fyra våtmarkerna. Skillnaderna för varje våtmark vägdes samman med invers-varians metoden för att få ett sammanvägt medelvärde. Analysen av läkemedel gjordes på nio läkemedel från Breitholtz et al. (2012). De nio valdes ut då de har pekats ut av Svenska Miljöinstitutet som intressanta ur ett avloppsreningsperspektiv. Excel användes för att göra enklare statistiska analyser mellan in- och utflöde i våtmarkerna. Slutligen gjordes en jämförelse mellan hoppkräftors skadeeffekter och läkemedelshalter genom att ta ut skillnaden i medelvärde mellan in- och utflöde.

    Resultatet från analyserna visade att när våtmarker användes som tilläggsrening minskade mortaliteten hos hoppkräftor för koncentrationerna 11,25 % och 90 % avloppsvatten. För koncentrationerna 22,5 % och 45 % fanns däremot ingen signifikant skillnad i mortalitet. Larvutvecklingskvoten minskade efter våtmarksbehandlingen för alla koncentrationer utom 90 %. Läkemedelshalten minskade i snitt med 30 % mellan inflöde och utflöde i våtmarkerna. För läkemedlen sulfametoxazol och oxazepam kunde dock en ökning ses efter behandling med våtmark. Ingen direkt trend kunde utläsas mellan läkemedelshalt och mortalitet hos hoppkräftor. Detta berodde troligtvis på att andra faktorer och föroreningar påverkade hoppkräftornas mortalitet och larvutvecklingskvot i högre grad än läkemedelshalterna.

    I studien kunde ingen slutsats dras om huruvida tilläggsvåtmarker är en effektiv reningsmetod med avseende på skadeeffekter hos hoppkräftor. Hoppkräftor är bra indikatorer på föroreningar i vattnet, dock är det svårt att bestämma vilka föroreningar som påverkar mest i detta fall. Detta medför att inga direkta samband mellan läkemedel och hoppkräftors mortalitet kunde påvisas i studien. De undersökta läkemedlen reducerades generellt. Eftersom mätningarna gjordes under vinterförhållanden då nedbrytningen i våtmarken är som minst effektiv bör resultatet ses som ett lägsta värde.

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  • 4.
    Ahlin, Erik
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Modellering av dagvattennät utgående från markhöjder2012Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    According to The Swedish Water and Wastewater Association (SWWA), a storm waternetwork must be able to handle a rainfall with a return period of 10 years. In order toevaluate whether a drain system is adequately dimensioned, a storm water model can beestablished. This requires knowledge about the levels at which the conduits are situated,and this information is insufficient in many areas. However, the pipes could largely beassumed to follow the topography and the pipes levels can be estimated from it.Therefore, the aim of this study was to develop a method for how the level of stormwater conduits could be assessed from the ground level, and the significance thismethod had for storm water modeling. A further aim was also to, according to thismethod; assess the storm water systems of the Lidingö community, which lackedinformation on the pipe levels. Furthermore, for the method to be useful it wasimportant to make it easily applicable even to large storm water networks.The method was developed using parts of the storm water network in Sundbyberg,Stockholm. The levels of the conduits were known beforehand, and an analysis of themresulted in a method where the depth of the manhole, which controls the levels of theconduits, was estimated to 2 m. An exception had to be made when the conduits were inreverse slope, in which cases horizontal slope was assumed.When evaluating the impact from the depth assessment on the runoff, the uncertaintyfrom the imperviousness was taken into account by using three different scenarios;unchanged, 30% lower and 30% higher imperviousness. The risk of flooding for eachone of the manholes was weighted from the results of these three scenarios. Thisresulted in a pressure level for each manhole, either above ground, below ground orinconclusive. This was done for the model with both known levels for the conduits, andwith the assessed levels. In order to evaluate how well the method for applying thedepth worked, the status of each manhole was compared between the two models.The conclusion from this study was that the method developed here, more or less gavethe same results as when the levels of the conduits were previously known.Discrepancies arose mainly in ditches, but also for a few landlocked areas and outlets.For the Lidingö storm water network, 18 % of the wells ended up with a pressure levelabove ground when applied to a rain with a 10 year return period. Another 16 % of thewells were inconclusive.

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  • 5.
    Ahlström, Marcus
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology.
    Online-instrumentering på avloppsreningsverk: status idag och effekter av givarfel på reningsprocessen2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The effectiveness of automated treatment processes within wastewater treatment plants ultimately depend on the quality of the measurement data that is given from the installed sensors. Sensor faults affect the control of the treatment plants and are often the reason different control strategies fail. Today there is a lack of standardized guidelines for how to organize and work with online sensors at Swedish wastewater treatment plants which limits the opportunities for treatment plants to reach their effluent criteria in a resource efficient manner. Much research has been done on ways to optimize control strategies but the role of sensors in the efficiency of the treatment plants has not been given the same level of attention. The purpose of this thesis has been to examine how instrumentation at wastewater treatment plants can be organized and structured to ensure good quality measurement data and to examine how sensor faults affect the treatment process.

    Within the thesis a literature study was conducted where instrumentation at wastewater treatment plants was examined. The effects of sensor faults were examined by simulating a pre-denitrification process in Benchmark Simulation Model no. 2 where off-sets (biases) and drift where added to measurements from different implemented sensors. The simulations showed that positive off-sets (0.10–0.50 mg/l) in an ammonium sensor within a cascaded feedback-loop adds to the energy consumption used for aeration by roughly 4-25%. It could further be shown that all types of faults in a DO sensor in the last aerated basin had significantly larger effect on the treatment process than the same fault in any of the other DO sensors in the preceding basins. If the last aerated basin is designed to have low DO concentrations the DO sensor in that basin is the most important DO sensor to maintain. Positive off-sets (200–1 000 mg TSS/l) in suspended solids sensors used for control of waste activated sludge flow contributed to large increases of ammonia, by 29-464%, in effluent waters. Negative drift in DO sensors showed that significant savings in aeration energy, roughly 4%, was possible to achieve with more frequent maintenance.

    Whether a sensor is affected by a positive or a negative fault, be it off-set or drift, will affect how much and in what way the treatment process will be affected. The study of sensor faults showed that the effect of a positive or a negative fault varied and that the effect on the treatment process was not linear. The effect of a sensor fault on the treatment process will ultimately depend on the implemented control strategy, settings in the controllers and on the controlled process.

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  • 6.
    Alzuhairi, Fatin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    A Quantitative Microbial Risk Assessment Associated with Cross-Connections in the Drinking Water Network in Combination with Hydraulic Modeling2022Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Drinking water companies have the technology and responsibility to deliver safe and high-quality drinking water to the water distribution systems network (WDN). However, many events within the WDN, such as cross-connections and backflow, might degrade water quality and pose public health risks to consumers. Cross-connection and backflow events may occur if there is physical contact between the external non-potable water source and the drinking water. When the pressure in the external source is greater than in the WDN, and when there are inadequate cross-connections controls, cross-connections and backflows may occur. This project aimed to investigate the circumstances that influence cross-connection and backflow events and estimate the health risk of infection. The method used for this study included hydraulic and water quality modeling EPANET to simulate the fate and transport of pathogens in the WDN during the outbreak. Besides, the quantitative microbial risk assessment QMRA was used to evaluate the health risks associated with cross-connections and backflow events due to ingestion of contaminated water. The modeled events included four reference pathogens (viruses: Norovirus and Rotavirus, bacteria: Campylobacter, and protozoa: Cryptosporidium) from four water types (wastewater, greywater, treated wastewater, and treated greywater). The simulation considered three potential pathogen load risk levels entering WDN: extreme, evaluated, and endemic. The results indicate that the factors that influence pathogen intrusion and consequently the risk of infection were the duration and intensity of the low-pressure event, the location of the cross-connection, and the pathogen concentration in water sources. The estimated daily risk of infection from cross-connection and backflow events generally exceeded the acceptable target level of 10−6 per person per day for all reference pathogens and modeled events. The exception was for the endemic risk level during the cross-connections with treated wastewater and greywater, where the risk was 10−7 and 10−10. Several measures can be implemented to manage and mitigate the risk of cross-connections, such as demanding plumbing installation procedures and backflow prevention devices and developing an early detection system to predict the cross-connection earlier before the outbreak happens to the system, for instance, by applying a machine learning system. 

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  • 7.
    Anandhi, Aavudai
    et al.
    Florida A&M Univ, Coll Agr & Food Sci, Biol Syst Engn, Tallahassee, FL 32307 USA;Florida A&M Univ, Coll Agr & Food Sci, Ctr Water Resources, Tallahassee, FL 32307 USA.
    Pierson, Don
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Limnology.
    Frei, Allan
    CUNY, Hunter Coll, Dept Geog, New York, NY 10065 USA;CUNY, CUNY Inst Sustainable Cities, New York, NY 10065 USA.
    Evaluation of Climate Model Performance for Water Supply Studies: Case Study for New York City2019In: Journal of water resources planning and management, ISSN 0733-9496, E-ISSN 1943-5452, Vol. 145, no 8, article id 06019006Article in journal (Refereed)
    Abstract [en]

    Evaluating the suitability of data from global climate models (GCMs) for use as input in water supply models is an important step in the larger task of evaluating the effects of climate change on water resources management such as that of water supply operations. The purpose of this paper is to present the process by which GCMs were evaluated and incorporated into the New York City (NYC) water supply's planning activities and to provide conclusions regarding the overall effectiveness of the ranking procedure used in the evaluation. A suite of GCMs participating in Phase 3 of the Coupled Model Intercomparison Project (CMIP3) were evaluated for use in climate change projections in the watersheds of the NYC water supply that provide 90% of the water consumed by NYC. GCM data were aggregated using the seven land-grid points surrounding NYC watersheds, and these data with a daily timestep were evaluated seasonally using probability-based skill scores for various combinations of five meteorological variables (precipitation, average, maximum and minimum temperatures, and wind speed). These are the key variables for the NYC water supply because they affect the timing and magnitude of water, energy, sediment, and nutrient fluxes into the reservoirs as well as in simulating watershed hydrology and reservoir hydrodynamics. We attempted to choose a subset of GCMs based on the average of several skill metrics that compared baseline (20C3M) GCM results to observations. Skill metrics for the study indicate that the skill in simulating the frequency distributions of measured data is highest for temperature and lowest for wind. However, our attempts to identify the best model or subgroup of models were not successful because we found that no single model performs best when considering all of the variables and seasons.

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  • 8.
    Anderberg, Hilda
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Olsson, Sofia
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Bjerklund, Frida
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Larsson, Therese
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Junegard, Frida
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Risker vid översvämning och åtgärdsförslag för MSB:s skola i Revinge2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    På skolan i Revinge utbildar Myndigheten för samhällsskydd och beredskap (MSB) personer inom områdena skydd mot olyckor och krisberedskap. Vid ett flertal tillfällen har Kävlingeån översvämmat skolområdet vilket resulterat i att verksamheten blivit stillastående i flera veckor. Grundvattennivån ligger nära markytan på skolområdet och platsen är därför extra känslig för översvämningar både från ån och extrem nederbörd.

    För att kunna minimera konsekvenserna vid en översvämning identifierades olika objekt, byggnader och områden, som i rapporten är benämnda som skyddsobjekt, som drabbas mest vid översvämning. För att ta hänsyn till att framtida väderförhållanden kan bli mer extrema undersöktes två klimatanpassade scenarier, höga flöden från ån och extrem nederbörd. Olika åtgärder mot översvämningar som potentiellt kan passa skolområdet togs fram och viktades utefter kostnader, lagar och skyddskapacitet.

    Skyddsobjekten som togs fram är skolans övningytor, kontorsbyggnader, hus med källare, spillvattenbrunnar, områden som kan sprida miljöfarliga ämnen, elskåp samt fordonshall/förråd. Skyddsobjekten viktades utefter översvämningskonsekvensernas direkta kostnader, hinder för utbildning samt fara för människor och natur, i relation till hur sannolikt det är att objekten blir översvämmade. Övningsytor, spillvattenbrunnar och områden som kan sprida miljöfarliga ämnen fick högsta prioritet.

    De åtgärder mot översvämning som undersöktes var gröna tak, regnmagasin, regnbäddar, träd, kontrollerad översvämningsyta och permanent vall. De fyra förstnämnda bedömdes billiga och lagligt sett icke komplicerade i relation till permanent vall och kontrollerad översvämningsyta. En summering av vilka skyddsobjekt varje åtgärd skyddar lades till. En effektivitetsfaktor togs fram i relation till vilka scenarier åtgärderna verkar mot och i vilken grad de kan motverka ett scenario på egen hand. Detta gav värderingen, från högst till lägst, permanent vall, träd, översvämningsyta, regnmagasin, regnbäddar och gröna tak.

    Som ytterligare åtgärder rekommenderas det att utesluta användning av källare helt och bestämmelser kring nybyggnation bör tas i relation till var det finns störst risk för översvämning på området. Ett förslag till MSB finns om att ta kontakt med Kävlingeå-projektet som arbetar med att utöka andelen våtmarker utmed Kävlingeån, där ett av målen för projektet är att motverka översvämningar. Arbetet drivs av Kävlingeåns Vattenråd, vilka också kan ha mer information kring hur regleringen av Vombsjön kan påverka risken för översvämning på skolområdet. 

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  • 9.
    Andersson, Amanda
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Utvärdering av prediktion och utfall av inläckage i bergtunnel: Fallstudie E4 Förbifart Stockholm2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Groundwater inflow to a rock tunnel is inevitable, but nonetheless important to limit. Otherwise both the surroundings and the tunnel itself risk becoming subject to damage. To prevent this, legal limitations are set for the inflow. Measurements are then made to ensure that the inflow does not exceed these limitations. When constructing a tunnel in hard rock, the limit objectives are hopefully met through the filling of rock fractures through grouting. Inflow predictions are made at an early stage of a tunnel project, both in order to establish the legal requirements but also as basis for grouting design. The aim of the work reported is to understand why these predictions in some cases deviate from the measured inflow. To accomplish this, a case study on two road tunnels in one of Sweden's most comprehensive infrastructure projects of all time, the construction of a motorway bypass around the capital Stockholm, is presented and assessed. Several causes of deviations between inflow predictions and observations in these two tunnels are suggested, most of them related to the hydraulic conductivity of the rock. Overall the rock quality seems to be worse than predicted. In one tunnel segment in particular, one cause of major deviations from inflow predictions is due to a fracture zone which has not been accounted for. These identified causes of increased inflow could have been foreseen in an early stage of the project, either through more extensive investigations or different interpretations of existing data. New inflow predictions have been made based on the suggested corrections. The result is consistently higher than the predictions made earlier and mostly less deviant from observations. This indicates that the real inflow is probably higher than initially predicted.

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  • 10.
    Andersson, Camilla
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Modellering av avrinning från gröna tak: Avrinningskoefficienter och modellparametrar2015Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Larger and denser cities result in increasing amounts of impervious surfaces in urban areas. This generates an increase in storm water runoff, as the rainwater is prevented from infiltrating in natural soils and instead flows along the paved surfaces. The increased amount of storm water runoff is liable to cause problems in areas where the storm water system has been designed to handle the amounts of runoff previously generated in the area. Upsizing the capacity of the pipelines is usually costly, and it is therefore desirable to instead reduce the load on the existing system. One way of achieving this is to cover the rooftops with vegetation, so called green roofs. Green roofs are growing in popularity and have the potential to reduce the rate and volume of runoff, as well as attenuating the peak discharge. There are however uncertainties regarding how their abilities are affected by for example the antecedent weather conditions and the moisture content of the roof, as well as by various storm events.

     

    The purpose of this Master’s Thesis was to study the possibility to simulate the runoff from green roofs using an existing function in the modelling software SWMM by US Environmental Protection Agency, and using Mike Urban by the company DHI. An additional objective was to use on of the designed models to evaluate how green roofs can affect the load on an existing storm water system. Measurements of precipitation, runoff and potential evapotranspiration were obtained from Veg Tech AB and AgroTech A/S. The measurements had been carried out at their demonstration site in Taastrup, Denmark, and included runoff from green roofs of three different thicknesses: 4 cm moss-sedum, 7 cm sedum-herb-grass and 11 cm sedum-herb-grass, as well as an impervious roof used as reference. Initial analyses of the data showed that the storage capacity increased with an increased roof thickness. The thicker roofs were able to completely retain the rainfall from larger storm events than what was the case for the thinnest roof. An analysis of the relationship between precipitation depth and runoff volume showed a stronger correlation for rains with 60 and 120 minutes duration than what was the case for shorter durations.

     

    Comparisons of the two models’ performance showed different strengths and weaknesses, and none of the models were able to simulate runoff in a way that was satisfactory in all aspects. Mike Urban generally gave a higher coefficient of determination but consistently overestimated the discharged volume for extended time periods. SWMM gave a better conformity in observed runoff than Mike Urban during the first months of the simulation period, but generally gave a time lag in the runoff hydrograph. For the 4 cm roof calibration, SWMM also gave a more correct long-time runoff volume, while both models performed similarly for the other roof thicknesses. In an example, one of the models was used to simulate the runoff from the MAX IV laboratory in Lund. The results showed that in order to avoid flooding in the fictitious downstream storm water network, there had to be a four times larger detention pond in the case where conventional roofs where used compared to the scenario using green roofs.

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  • 11.
    Andersson, Karolina
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Igensättning av långsamfilter i Östby vattenverk i Kramfors: studie av påverkande faktorer2006Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Östby waterworks in the community of Kramfors has since 2003 had problems of fast clogging of the slow sand filters. As the clogging appears more often, they must be cleaned more frequently which has made the drinking water preparation difficult. Wintertime it has sometimes been impossible to clean the filters which has led to their closing and this has influenced the water quality negatively.

    The waterworks is a surface waterworks which takes its raw water from the lake Sjöbysjön. The water is flocculated and filtered in a contact filter with the flocculent EKOFLOCK 91. Thereafter it is alkalinized before it reaches the outdoors placed slow sand filters. After the filters the water is alkalinized and disinfected before it reaches the customers.

    This thesis work has looked into which factors influence the clogging and trials have been made in order to optimize the waterworks and thereby reduce the clogging. The raw water has been studied with aspect to biology and chemistry, the filtered water has been studied with aspect to chemistry and also the pressures in the slow sand filters have been studied.

    The colour of the raw water from Sjöbysjön and its catchment area has increased since the beginning of the 90-ies and also the bio volume has increased in the lake.

    The contents of aluminium before the slow sand filters are far higher than the contents after, which leads to the conclusion that aluminium is accumulated in the filters. The differential pressure over the sand bed increases with time after a cleaning. This indicates an accumulation of particles which increases with the load. Observations of the filter surface before cleaning showed that it was covered by a brown, jelly-like film. The internal resistance in the filter beds increases successively after a cleaning and one month after cleaning it is highest in the upper part of the sand bed. All this points to that flocculated aluminium is gathered in the slow sand filters, on the surface, causing clogging.

    While the thesis work has been going on a process of alkalinizing before the contact filters has been reengaged and this has influenced the flocking of organic materials. When raising the pH the dose of flocculent was increased and this combined increased the amount of flocculated material. The contact filters could not bear this increased amount of flock load but showed instead a breakthrough.

    In a few lab scale trials the flocking pH was varied as well as the dose flocculent to the raw water and after this the water was filtrated. A tendency was seen that the separation of aluminium, colour and turbidity increased with increasing pH and dose flocculent. At the pH 6.2 and the chemical dose of 60 g/m3 the content of aluminium, the colour and the turbidity showed the lowest values in the filtrate.

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  • 12.
    Andersson, Magnus
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Ökad grundvattenbildning genom pumpning av salt grundvatten från berggrunden på Gotland2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Because of an increased shortage and an increased demand of fresh water on Gotland, the possibility to pump saline groundwater and thereby locally lower the saltwater interface and increase recharge was investigated. With the saltwater interface further down in the bedrock, deeper wells could be drilled and extraction of more fresh water would therefore be possible.

    To examine the concept, a groundwater model was created to simulate the idea on a region of the peninsula Sudret on the southern part of the island of Gotland, Sweden. To be able to simulate the idea of pumping groundwater in an aquifer with a mix of saline and fresh groundwater of variable density, a model was built using the groundwater modelling program GMS in combination with the modules/program codes MODFLOW, MT3DMS and SEAWAT. With these modules, the model can handle the complex situation with extraction by pumping from groundwater of variable density and changes of salt concentration over time. A three dimensional geological model over the area produced by SGU was used as a foundation for building the model.

    Since no site specific surveys considering groundwater levels and flow/dispersion parameters have been previously undertaken in the study area, the parameters of the model were chosen according to literature and findings from similar projects conducted in the past. First, a model was developed to simulate a stable saltwater interface without pumps. Parameters were changed until a groundwater level close to the surface of the model was given and the saltwater interface ended up around the transition between limestone and sandstone. When the model generated desirable results, it was further developed to include the extraction of saltwater by pumping. 

    Results from the project showed that the concept of lowering the saltwater interface by pumping works, with an increased recharge corresponding to 55 % of the extracted saltwater volume. Because of a lack of site specific parameters, the results should not be seen as more than an indication that the concept works. 

    Furthermore, geohydrological measures should be made to provide local parameters regarding flow and dispersion for more reliable future models. To gain a greater understanding of how well the concept would work in reality, further development should be undertaken to include fresh groundwater extraction to assess how that would affect the position of the saltwater interface.

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  • 13.
    Anderzon, Sofia
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    A valuation of ecosystem services from blue-green infrastructure for stormwater management2021Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The ongoing urbanization leads to densification and growth of cities, which replaces natural areas with hard surfaces. Precipitation is then more likely to runoff as stormwater than to be detained locally. Also, precipitation is predicted to be increasing as an effect of climate change. Traditionally, stormwater has been handled by draining it in underground pipes. As a complement, blue-green infrastructure (BGI) can be used to take care of the increased amount of stormwater. BGI is vegetation and water-based systems that intend to restore the natural flows of water. It does, however, not only provide services for stormwater management but also other services that contribute to human welfare. These are provided for free by nature and are called ecosystem services. By illustrating the value of ecosystem services, the motivation of implementing more BGI can increase. The aim of this project was to provide guidance on how to value ecosystem services that BGI can provide at a district level. The valuation was to be semi-quantitative with the grades 1-5. To do so, ecosystem services were identified and given indicators that could illustrate the extent of the ecosystem services’ presence.

    Seven different BGI for stormwater management were studied, to determine which added values they can bring into urban settings. The BGI were green roofs, trees, rain gardens, swales, detention basin, detention ponds and attenuation storage tanks. Nine ecosystem services provided by these BGI were then identified. These were flood protection, water treatment, local climate regulation, air quality control, environmental noise control, erosion prevention, recreation, social relations and biodiversity. 

    Indicators were identified for each ecosystem service through a literature study. It was noted that to value the ecosystem service, it was not enough to only value the presence of the indicators but also necessary to estimate the demand or need for the ecosystem service. Therefore, questions were formed that could help determine the demand for the ecosystem service. The valuation was then based on how well the presence of the ecosystem service corresponded to the demand of it. 

    After using this valuation method on a case study, it was concluded that this type of valuation is useful for reconstruction projects in an early stage, to illustrate what functions and demands that need to be considered to obtain more ecosystem services. It can then be used for comparison of different proposals, to see which one provides the most ecosystem services. The valuation is conceptual rather than specific. It is useful as it can include any type of ecosystem service but lacks the perspective of costs.

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  • 14.
    Arvidsson, Diana
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Utredning av avloppsprocessers påverkan på recipientens mikrobiologiska status2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Depending on the efficiency of the processes used in a wastewater treatment plant, the recipient receives watercontaining various concentrations of microorganisms. These microorganisms might infect people using therecipient for recreational purposes. The thesis aims to investigate how some process choices affect the concentrationsof microorganisms in sewage and how the concentration can be monitored with the use of other waterquality measurements. Lastly the microbial degradation after discharge in a lake was investigated. Process choiceswere evaluated through sampling before and after two biological treatment steps, one sand filter facilityand one disc filter facility. The obtained results demonstrate that among the investigated alternatives, a biologicalstep using biofilm is the most efficient for removing microorganisms, followed by sand filtration and leastefficient with high variability was disc filtration. The literature review suggests that the use of ozonation forreducing pharmaceutical residues could be efficient in reducing microorganisms, but the required dosage is notuniformly established in previous research. Statistical analysis on water quality measurements with Kendall’sTau and Partial Least Squares did not appear to be a good substitute to use for monitoring and prediction ofbacterial concentrations. The water quality of the recipient, especially the transparency for UV-light, is moreimportant for maintaining good bathing water quality than the outflow concentration of microorganisms in thesewage. In a small case study, it was shown that an official bathing site is not at risk for acute microbiologicalcontamination even when extreme rainfalls causes overflow in the upstream waste water treatment plant.

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  • 15.
    Arvidsson, Diana
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Cederwall, Emma
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Litsmark, Sofia
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Sjödell, Birgitta
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Wilson, Johan
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Östrand Myrlund, Anna
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Digidrick: Utvärdering av behov och begränsningar för digitala lösningar i svenska vattenverk2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Sverige anses ha en välfungerande dricksvattenproduktion på grund av stor tillgång på råvatten med god kvalitet. För att kunna möta utmaningarna i framtiden, så som klimatförändringar och en ökad befolkning, krävs en ökad digitalisering på vattenverken för att erhålla en säker dricksvattenproduktion.

    Projektet syftar till att utreda vilka hinder och möjligheter som finns för en ökad digitalisering av övervakning och styrning på svenska vattenverk. Detta har gjorts genom en litteraturstudie som bidragit med kunskap för utformningen av en enkätundersökning där vattenverk fått svara på frågor gällande digitalisering av övervakning och styrning. Enkäten skickades ut till 370 vattenverk i Sverige varav 14 av dessa svarade och utgör underlaget för resultatet i denna rapport. Resultatet visar att samtliga vattenverk som har besvarat enkäten har ett behov av en ökad digitalisering av övervakning och styrning som utgörs av

    • Tidiga varningssystem

    • Förbättrad övervakning

    • Styrning av beredningsprocessen

    • Modeller för processer

    • Förbättrad IT-säkerhet

    Av resultatet framgår även att det finns en viss spridning av vilka behov som vattenverken anser som mest angelägna. I många fall upplever de 14 vattenverken organisatoriska, tekniska och ekonomiska hinder för att implementera eller utveckla digitaliseringen av övervakning och styrning. Den låga svarsfrekvensen gjorde att det inte erhölls en generell bild av svenska vattenverks syn på en ökad digitalisering.

    Inom projektet har även ett modellverktyg för kemisk fällning konstruerats med syfte att undersöka automatisk online-dosering av koaguleringsmedlet Al2(SO4)3* 14 H2O (ALG). En jämförelse mellan online-mätningens direkta dosering och en fördröjd mänsklig dosering har gjorts för att stödja argumentet om varför en automatisk dosering kan vara fördelaktig ur ett ekonomiskt och kvalitetsmässigt perspektiv. Undersökningen visade att det finns möjlighet att spara 330 000 SEK/år i enbart kostnad för ALG, vid en övergång från manuell till automatisk dosering.

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  • 16.
    Aulin, Beatrice
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Linnea, Henriksson
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    The water balance in Graminha Basin2014Student paper other, 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today, only 7 % of the Atlantic Rainforest, that once covered Brazil, remains scattered across the southern parts of the country. As the forest is rapidly disappearing, the government of Brazil has emerging interest of preservation. Thus more and more areas are turned into national parks and reserves. At the outskirts of one of these reserves, the Iracambi research station is situated. The center makes an effort to carry out applied research to find methods of preserving and learning about the forest. It is within that context the project described in this report has been performed. The project aimed to establish a water balance over Graminha Basin, the main river in the Iracambi research area. By doing this the understanding of the fluctuations of the amount of water in the ecosystem could increase. An important part of the objective was also to assess which methods can be used practically at Iracambi.The project was carried out during the rainy season from February 13th to April 12, 2012. During this time the water flow was measured at five stations along the river, using a current meter and instant slug-injection. Between six and fifteen flow measurements were made at each station. Slug- injection was generally the most suitable gauging method to use in the area. Precipitation was measured at two points. Evaporation was measured using an evaporation pan, and also calculated using the Penman-Monteith equation. Even though, the parameterization of the Penman-Monteith needs to be improved it was deemed to be the more suitable method for the area.The results give a rough estimate of the water balance during the period. It was concluded that the storage decreased during the project period. Based on the flow measurements and observations it was concluded that the areas covered by forest were less affected by the floods that occurred during heavy rainfalls than the areas covered by grass. Further on, the result of this report indicates that the Iracambi research station can continue to carry out assessments for changes in water flow, rainfall and evaporation with the simple equipment used in this project. However, more expensive and advanced equipment would be beneficial to establish a more accurate water balance.

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  • 17.
    Bachofner Gran, Clara
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Grundvattenmodellering inom Loddby före detta Sulfitmassabruk2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Loddby sulphite pulp factory was during its active days located next to Loddbyviken, approximately five kilometers north of Norrköping. Production of sulphite paper pulp was conducted between the years 1899 and 1977 within an area of 18,6 hectares. The former sulphite pulp factory is today considered polluted to the extent that it is entailing a great risk for human health and the environment, but to be able to decide what measures to take, the hydrogeological conditions in the area need to be clarified.

    The objective of this master’s thesis was to map the groundwater flow pattern within Loddby former sulphite pulp factory by developing a site-specific groundwater model with the groundwater flow model MODFLOW in the software Groundwater Modeling System (GMS). The master’s thesis also aimed at examining how the groundwater movement in the area is affected by fluctuations in the water level of Loddbyviken. A conceptual model was initially created to describe the hydrological system in a simplified way with regards to the geology, hydrology and climate within the area. The model domain was delimited by topographical water divides and hydrological boundaries, and was thereafter divided into three horizontal layers based on the main materials that have been identified during investigations within the area: filling material, clay and till.

    In GMS, the model domain was divided into a 5x5 meter grid and its borders were assigned appropriate boundary conditions. By interpolating the three model layers from scatter point data of known geology, the conceptual model could be described mathematically within the software. To increase the reliability of the model, the hydraulic conductivities of the materials were then calibrated against observed hydraulic head in several groundwater monitoring wells in the area. After the calibration, the hydraulic conductivities of the filling material, clay and till were 2,1ˑ10-4 m/s, 5,7ˑ10-7 m/s and 3,9ˑ10-5 m/s respectively. A sensitivity analysis was then performed in order to examine how the values of hydraulic conductivity and groundwater recharge would affect the model results.

    Simulations with the calibrated model showed that the groundwater generally moves from the western parts of the area towards Pjältån and Loddbyviken in the north and east. However, it moves around the areas where the impermeable bedrock is close to the ground surface. Changes in the water level of Loddbyviken proved to have some effect on the amount of water in the system, but they did not entail a greater influence on the groundwater movement pathways in the area. The sensitivity analysis showed that the model was very sensitive regarding the groundwater recharge and the hydraulic conductivity for the till. A very low conductivity of clay turned out to lead to some modeling difficulties and the conductivity of the filling material showed to only have a small effect on the result.

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  • 18.
    Bar-Am, Maya
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Spett, Isak
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Svanberg, Adam
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Thelander, Frida
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Viklund, Simon
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Widengren, Veronika
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Zaff, Sandra
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Infiltrationsbassängers kapacitet och  kontroll med avseende på  infiltrationsmängd och igensättningar: En jämförelse av plan och sluttande sandbotten2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    För att framställa konstgjort grundvatten används idag infiltrationsbassänger som främsta metod i Sverige. Ytvatten pumpas upp till bassänger med sandfilter i botten där vattnet kan infiltrera för att sedan spridas och vidare filtreras genom underliggande rullstensås för att slutligen fylla på grundvattenmagasinet. I infiltrationsbassänger sker dock igensättningar till följd av lösa partiklar, kemiska utfällningar eller att porerna i sanden växt igen av biologiska processer. Detta är ett oundvikligt problem då allt ytvatten som används innehåller mer eller mindre löst kol. Dessutom sker igensättningarna i nuläget på okänd yta och djup. Uppsala Vatten och Avfall AB har en hypotes att en bassäng med sluttande botten, istället för den nuvarande plana botten, skulle kunna ge ökad kontroll över var igensättningen sker. Syftet med projektet var att ta fram underlag till Uppsala Vatten och Avfall AB och utreda om deras hypotes stämmer. Frågeställningen för projektet var hur kontrollerat och effektivt infiltrationen sker med avseende på igensättning i en infiltrationsbassäng med plan botten jämfört med en bassäng med sluttande botten. För att undersöka detta sammanställdes en litteraturstudie och sakkunniga inom området tillfrågades för utlåtande via både e-post och personlig kontakt. Ett flertal olika beräkningsmodeller skapades och dessa modeller användes för att beräkna horisontella hastigheter, storlek på infiltration, vattenpelare, tider att fylla bassänger med mera. Modellerna programmerades för att kunna varieras med olika värden för olika parametrar, detta för att koden enkelt skulle kunna anpassas efter olika förutsättningar. Resultatet av beräkningarna med antagna begynnelsevärden visar att den totala infiltrationen för en plan bassäng kommer att vara betydligt större än den för en sluttande bassäng. Detta förklaras med att den plana bassängen har en dubbelt så stor volym och på grund av detta en dubbelt så stor vattenpelare. Om volymen istället skulle vara lika stor för de båda typerna av bassängerna skulle det dock vara svårare att avgöra vilken som infiltrerar mest.

    Utifrån studiens resultat är det dock svårt att presentera tydliga slutsatser. Detta eftersom beräkningarna gjorts på begynnelsevärden och antaganden som inte speglar verkligheten helt. Det finns däremot indikationer på att igensättning i en bassäng med sluttande botten sker gradvis över filtersanden, vilket är till fördel för ökad kontroll. Drift och underhåll av bassängen kommer inte skilja särskilt mycket mellan en plan eller en sluttande bassängbotten. Det som dock förblir svårt att avgöra är vilket alternativ av botten som ger en effektivare infiltration. Detta då data saknas kring hur påverkad den hydrauliska konduktiviteten i filtersanden blir av igensättningar.

    Projektet är komplext och det kan därför vara en god idé att följa upp teorin med praktiska försök. För fortsatta undersökningar bör det testas hur en sluttande botten kommer att fungera i praktiken, närmare bestämt hur skillnaden i infiltrationskapacitet skiljer sig och vad skillnaden i drift är för en plan gentemot en sluttande botten. Vidare bör det undersökas om sanden förflyttar sig på grund av isbildning vintertid för en sluttande bassängbotten, om det kan vara en god idé att ha ett djupare sandlager i den djupare delen av bassängen samt huruvida idén att exempelvis använda en mer finkornig sand i den djupa delen av den sluttande bassängbotten är tillämplig.

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  • 19.
    Barkefors, Disa
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    The Influence of Infiltration Capacity and Antecedent Soil Moisture Conditions on Urban Pluvial Flooding2023Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Urban pluvial floods occur during extreme rain events and both occurrence and magnitude of these floods are expected to increase. Preserving or constructing green areas in urban areas has been shown to mitigate and control these floods. The common way to evaluate flood risks is to set up a rainfall-runoff model, but these studies are often case related and only investigate the soil characteristics for that specific case. Multiple studies have also stated that the difference between major and minor flooding effects is connected to the antecedent soil moisture content. This thesis attempts to investigate how different soil characteristics influencing infiltration affect the hydraulic response in two Swedish urban catchments and if antecedent soil moisture is a critical factor.

    To evaluate the hydraulic response, a two-dimensional surface runoff model of two different urban catchments was forced with a hyetograph of a CDS-rain with a return period of 100 years. The simulations were conducted with three different soil types for all urban green areas: clay, sandy loam and sand, and three different antecedent soil moisture contents for clay and sandy loam. Flood extent and discharge from catchment area was evaluated, as was flood depth and overland flow in 16 chosen evaluation points.

    The results showed that with decreasing infiltration rate of a soil and with increasing antecedent soil moisture content, the severity of the flood and discharge at the catchment outlet was increased. It was also concluded that soil type affects flood extent, flood depth, overland flow and discharge from catchment to a greater extent than antecedent soil moisture.

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  • 20.
    Basirat, Farzad
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Jung, Byeongju
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Institute of Geoscience and Mineral Resources (KIGAM), Daejeon, South Korea.
    Yang, Zhibing
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Numerical simulation of geological storage of CO2 with impurities in large scale saline aquiferManuscript (preprint) (Other academic)
  • 21. Bergenstråle, Terese
    Effekten av att separera ett befintligt kombinerat system till separat spill- och dagvatten: Vasastan, Stockholm2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

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  • 22.
    Bergkvist, Maria
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Björkman, Lovisa
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Flensburg, Jonas
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Fredriksson, Ellen
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Hagström, Matilda
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Nicolaisen, Tor
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Småskaliga avloppsreningsverk på Västerås landsbygd2022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    I denna studie undersöktes marknaden för småskaliga avloppsreningsanläggningar i syfte att ta fram ett eller flera förslag för hantering av avloppsvatten för 50–200 hushåll. Studien utfördes på uppdrag av Mälarenergi Vatten AB som ser ett ökat behov av avloppsreningssystem på Västerås landsbygd. Marknaden undersöktes genom en litteraturstudie där avloppsreningsverk från olika leverantörer studerades och jämfördes. Utöver det granskades vilka utsläppskrav som ställs på reningssystem i den aktuella storleken samt vad som krävs för att det renade avloppsvattnet ska kunna återanvändas för bevattning. Olika reningstekniker som är vanliga för mindre avloppsanläggningar studerades. För att bedöma de olika avloppsreningsanläggningarna utformades en metod med poängsättning baserad på krav i lagstiftningen gällande skyddsnivåer samt i samråd med Mälarenergi Vatten AB. Syftet med metoden var att avgöra vilket eller vilka av avloppsreningsverken som är mest lämpliga att använda utifrån kravbilden som ställdes. Bedömningsmaterial till metoden hämtades från företagen i form av reningsprestanda.

    Studien visade att det finns ett flertal småskaliga avloppsreningsverk samt en rad olika tekniker som var lämpliga för 50–200 hushåll. Reningsverken som jämfördes kom från företagen BioKube, Biovac, Conclean, Klaro, Topas och 4everegreen. Samtliga reningsverk levde upp till hög skyddsnivå med avseende på reduktion av Ntot , Ptot samt BOD. Reningsverken från Conclean och Klaro fick högst poäng i jämförelsen och ansågs därmed som lämpligast. Avloppsanläggningar i storleken 50–200 hushåll saknar utsläppskrav, det är i stället upp till VA-huvudmannen i varje kommun att bestämma vilka utsläppsvillkor som ska gälla. Arbetet med återanvändning av renat avloppsvatten resulterade i att kraven för bevattning presenterades. Det fastställdes däremot inte om det går att återanvända avloppsvatten från reningsverken som undersöktes.

    Utifrån studien går det inte att med säkerhet fastställa vilket system som är mest lämpligt att använda på Västerås landsbygd. I studien har endast reduktion av Ntot, Ptot och BOD värderats, vilket ger en bra bild av systemets reningskapacitet men en bristfällig helhetsbild. Vid anläggning av ett reningsverk behöver ytterligare parametrar som kostnad, total miljöpåverkan samt val av plats tas i åtanke. Dessa parametrar har inte lyfts i denna studie.

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  • 23.
    Berglund, Petter
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Cost-benefit analysis for sustainable stormwater management: A case study for Masthuggskajen, Gothenburg2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Densication and intensied precipitation patterns due to climate change, has increased

    the need for sustainable stormwater management. Sustainable stormwater management

    can be implemented as blue-green infrastructure (BGI), which integrates green features

    for natural inltration and detention such as green roofs and rain gardens. Through the

    use of BGI, added values can be provided as ecosystem services. Authorities and organizations

    in Sweden imply the need for valuation of ecosystem services for future integration

    in decision-making. This thesis include monetary estimations of ecosystem services within

    the use of a cost-benet analysis (CBA), for two alternatives of stormwater management

    in Masthuggskajen, Gothenburg. The applied valuation methods are methods commonly

    used in economic analysis. The ecosystem services identied and monetarily estimated as

    benets within this project were 

    ood protection, water treatment, air quality regulation,

    noise regulation and added recreational value. The result of the CBA indicated that the

    most protable alternative was considered to be the implementation of BGI rather than

    underground solutions.

    The ecosystem services contributing the most to the result was added recreational value,

    noise regulation and 

    ood protection. A sensitivity analysis was concluded by altering

    the value of costs and benets. Further analysis of the uncertainty in monetary estimates

    is of importance in order to integrate ecosystem services in decision-making.

    The diculty in covering the full extent of benets generated by BGI indicates the need of

    complementary tools in decision-making. However, this study highlights the importance

    of inclusion of ecosystem services in decision-making.

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  • 24.
    Bergman, Karin
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Berkelund, Linn
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Nylander, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Olsson, Malin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Renström, Terese
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    HYDROGEOLOGISKA FÖRHÅLLANDEN I GÄVLEÅSEN: Analys av stabila syreisotoper och kemiska parametrar samt beräkning av flöden i Gävleåsen2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Detta projekt behandlar hur vatten rör sig i Gävleåsen, det vill säga åsens hydrogeologiska förhållanden. Gävle kommun tar sitt dricksvatten från Gävleåsens grundvattenmagasin. För att öka grundvattenbildningen i åsen används konstgjord infiltration av åvatten och grundvatten genom infiltrationsbassänger, infiltrationsbrunnar och en sprinkleranläggning. Projektet initierades med bakgrund att grundvattennivåerna i Gävle kommuns grundvattentäkt sjunker på grund av vattenuttaget. Syftet med projektet var att bestämma om variationer i halt löst syre, organiskt material, an- och katjoner samt stabila syre- och väteisotoper kunde användas för att förklara de hydrogeologiska förhållandena i Gävleåsen. Även storleken på flödet uppströms och nedströms om infiltrationsanläggningen samt blandningsförhållandet nedströms skulle fastställas.

    Tre modeller över hur flödet varierade i åsen utformades på grund av den stora osäkerhet som fanns vid uppskattning av åsens mättade hydrauliska konduktivitet som användes vid flödesberäkningarna. I den första modellen antogs att flödesmassbalansen i åsen stämde, det vill säga att flödet nedströms var en summa av flödet uppströms om och flödet från infiltrationsanläggningen. Den andra modellen byggde på att det skedde ett okänt nettoutflöde från åsen mellan flödet uppströms och flödet nedströms om infiltrationsanläggningen. Att vatten istället skulle ha tillkommit till akviferen från exempelvis Gavleån eller genom inträngning av äldre grundvatten undersöktes med den tredje modellen. Uppställning av en isotopmassbalans för de olika modellerna tydde på att alla modeller kunde vara en möjlig bild av hur flödena i Gävleåsens akvifer förhöll sig till varandra och infiltrationsflödet genom infiltrationsanläggningen.

    Vid beräkning av blandningsförhållandet mellan grund- och åvatten nedströms om infiltrationsanläggningen visade både syreisotopsberäkningar och beräkningar med kloridjoner att cirka 25 procent åvatten tillkommit i akviferen. De kemiska parametrarna löst syre och organiskt material visade sig inte vara lämpliga som spårämnen för att bestämma källor till ett flöde. Dock kan dessa parametrar användas för att bedöma om det skett en förändring i vattenkvaliteten.

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  • 25.
    Björkman, Helena
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Stabilitetsberäkningar och åtgärdsförslag vid islast på Skålandammen2005Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Hydropower is an important source of energy in Sweden and accounts for about 46 % of the total energy production. Sweden has about 1 200 hydropower plants and with the intention of raising the pressure head of the water and to store water, dams are built by the power plants. The storage reservoirs make it possible to adjust the energy production by demand and season. Dams in connection to the reservoirs are subjected to additional loading during periods of high floods or when an icecap in the winter is formed on the reservoirs. In order to maintain the dam safety, the power companies in Sweden are working with guidelines for dam safety from RIDAS. An important part of the work of dam safety is FDU that is carried out with purposes of improving the work of dam safety. A FDU made for the Skålan dam in the River of Ljungan showed that the levels of the safety factors for sliding and overturning of the dam was not fulfilled when subjected to loads from an icecap. The object of this thesis was to follow up the FDU and by carrying out extensive stability calculations on all parts of the Skålan dam, investigate what safety factors the different parts will get and also investigate some proposal measures in order to increase the dam stability.

    The stability calculations for the dam have been performed according to directions in RIDAS at four loading cases. Loading case I and II means a water level to the retained water level and an ice load of 200 and 100 kN/m respectively. Loading case III and IV means a situation without ice load but with a water level to the retained water level respectively a water level to a meter above the retained water level. The stability of the dam was studied with regards to sliding and overturning. The results from the stability calculations showed for both loading case I and II that the majority of the parts of the Skålan dam did not fulfill the levels of the safety factors. The calculations also showed that some parts of the dam did not fulfill the stability criteria of sliding at loading case III, which implies that these parts of the dam actually have not enough weight.

    The measure proposals studied were the ice preventive measures IR-elements and circulation of the deep warm water and the stability increasing measure with pre strained rock anchorages. The net present value (NVP) for the different measures were calculated with a life length of the dam estimated to 60 years. The results from the calculations of the NVP showed that the most economically feasible measure is circulation of the water but when considering the results from the stability calculations, the most suitable measure is the rock anchorages. Therefore, a combination of rock anchorages on parts which not fulfills the stability criteria in combination with circulation of the water is suggested to be the best measure.

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  • 26.
    Blennow, Kristina
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Återvinning av näringsämnen från hushållsspillvatten med omvänd osmos2005Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Hammarby Sjöstad is a new district in Stockholm with high environmental standard. Stockholm Water Company evaluates a local wastewater treatment plant with cutting edge technology. The first step is an experimental treatment plant (Sjöstadsverket) with four parallel lines of treatment, each with a capacity to treat wastewater from 150 persons. Within the membrane technology subproject the possibility of using reverse osmosis (usually called RO) to regain nutrients is examined.

    Reverse osmosis separates the incoming water in a clean permeate and a concentrate that, as the name indicates, is a more concentrated version of the incoming water. Using this method in wastewater treatment, a solution high in nutrients can be obtained without the use of chemical precipitation agent and with no production of sludge. The solution can then be recycled to use on farmland. The disadvantages of the RO technology include high energy consumption and sensitivity to membrane fouling.

    The aim of this study was to investigate the possibility of using RO at Sjöstadsverket and, if possible, to evaluate the chance of obtaining concentrate that can be accepted as a fertiliser and permeate that falls below emission limits. The experiments were carried out with an RO plant with three membranes in series operated in batch mode; the dimensioned permeate flow being 100 l/h. The incoming water was permeate from a membrane bioreactor in the majority of the trial runs.

    The results show that RO can be used in at least one of the lines of treatment. However the permeate exceeds the emission limits (phosphorus: 0,15 mg/l, nitrogen: 6 mg/l) while concentration in the concentrate is still too low. The limiting factor seems to be phosphorus. This could be solved with pre-precipitation of phosphorus or by reconstructing the RO plant to a two-stage system. The quota heavy metal – phosphorus in the concentrate is lower than the limit imposed by the Swedish Environmental Protection Agency but much higher than in human urine.

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  • 27.
    Blomstrand, Patrik
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Systems and Control.
    Jemander, Rasmus
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Systems and Control.
    Systemteknisk studie av pumpstyrning på Henriksdals nya reningsverk2017Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The population of Stockholm is increasing and with it the amount of wastewater that needs treatment. To cope with the increase, Henriksdal wastewater treatment plant (WWTP) in Stockholm, Sweden, is currently being expanded into the worlds largest WWTP using membrane bioreactor (MBR) technology. The plant will be controlled to a greater extent by pumps and good control is therefore vital to maintain operational stability and an energy efficient process. To analyse the intricate system of pumps and equalisation in tunnels a dynamic model is required.One reason for expanding Henriksdal WWTP is the decommissioning of Bromma WWTP. Wastewater from Bromma will be diverted to Henriksdal through a large tunnel which can be used for flow equalization. To examine whether flow equalization in the tunnel can even out diurnal variations and extreme rain events, water flow in the tunnel and throughout the WWTP was modelled. Models of the tunnel, pumps and basins were made in the programming language C and then merged with different controllers in Matlab/Simulink. To simulate different scenarios for the year 2040, data for the rainy year of 2012 was increased to match the expected population for 2040.Based on simulations for a scenario with dry weather the possibility for flow equalization could be shown. It required a thought-out control strategy for the control of Bromma pumping station based on flow measurements from several other inflows to the WWTP. The control strategy also proved adequate in handling downpours by increasing the amount of waste water subjected to biological treatment. When simulating snow melt or heavy rain, damming in the Bromma tunnel could help to prevent overflow if no strict boundaries were used for the water level in the tunnel. With a maximum allowed water level of 10 m it was, however, possible to dam the first flush containing high concentrations of pollutants and nutrients.Flow equalization makes it easier to maintain even levels in the basins for the return activated sludge (RAS), which in turn makes it easier to maintain high levels in said basins. Higher levels in the RAS-basins leads to reduced energy consumption. In the event of further development of the model, it is possible to add calculations of energy usage for the pumps, which would facilitate further optimization of controllers and their parameters.

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  • 28.
    Blum, Kristin M.
    et al.
    Umea Univ, Dept Chem, S-90187 Umea, Sweden..
    Norström, Sara H.
    Umea Univ, Dept Chem, S-90187 Umea, Sweden..
    Golovko, Oksana
    Univ South Bohemia Ceske Budejovice, Fac Fisheries & Protect Waters, South Bohemian Res Ctr Aquaculture & Biodivers Hy, Zatisi 728-2, Vodnany 38925, Czech Republic..
    Grabic, Roman
    Univ South Bohemia Ceske Budejovice, Fac Fisheries & Protect Waters, South Bohemian Res Ctr Aquaculture & Biodivers Hy, Zatisi 728-2, Vodnany 38925, Czech Republic..
    Järhult, Josef D.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infectious Diseases. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology.
    Koba, Olga
    Univ South Bohemia Ceske Budejovice, Fac Fisheries & Protect Waters, South Bohemian Res Ctr Aquaculture & Biodivers Hy, Zatisi 728-2, Vodnany 38925, Czech Republic..
    Söderström Lindström, Hanna
    Umea Univ, Dept Chem, S-90187 Umea, Sweden.;Umea Univ, Dept Publ Hlth & Clin Med, Occupat & Environm Med, S-90187 Umea, Sweden..
    Removal of 30 active pharmaceutical ingredients in surface water under long-term artificial UV irradiation2017In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 176, p. 175-182Article in journal (Refereed)
    Abstract [en]

    This study investigated the i) kinetics, and ii) proportion of photolysis of 30 relatively stable active pharmaceutical ingredients (APIs) during artificial UV irradiation for 28 d in ammonium acetate buffer, filtered and unfiltered river water. Buffer was included to control removal kinetics under stable pH conditions and without particulate matter. Dark controls were used to determine removal due to other processes than photolysis and calculate the proportion of photolysis of the total removal. The removal of each API in each matrix was determined using online solid phase extraction/liquid chromatography tandem mass spectrometry (online SPE/LC-MS/MS). Most APIs transformed during the 28 d of UV irradiation and the dark controls showed that photolysis was the major removal process for the majority of the APIs studied. The half-lives ranged from 6 h (amitriptyline) in unfiltered river water to 884 h (37 d, carbamazepine) in buffer. In unfiltered river water, the proportion of APIs with short half-lives (<48 h) was much higher (29%) than in the other matrices (4%), probably due to additional organic carbon, which could have promoted indirect photolysis. Furthermore, two APIs, memantine and fluconazole, were stable in all three matrices, while alprazolam was stable in buffer and unfiltered river water and four additional APIs were stable in buffer. Considering the relatively long-term UV-exposure, this study enabled the investigation of environmentally relevant half-lives in natural waters. Many APIs showed high persistence, which is environmentally concerning and emphasizes the importance of further studies on their environmental fate and effects.

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  • 29.
    Boklund, Ingrid
    Sveriges lantbruksuniversitet.
    Ekosystemtjänster & grönstrukturplanering: Att synliggöra ekosystemtjänsternas nytta och värde i den kommunala planeringen med hjälp av ArcGIS-verktyget Matrixgreen2015Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Ecosystem services are the direct and indirect contributions of ecosystems to human well-being. Clean air, clean water, pollination and biodiversity are all examples of ecosystem services that humans depend on and whose value needs to be integrated into decision-making processes in all different levels of society. Local authorities have an important role in this as they at local level through spatial planning have the possibility to steer development towards more sustainable solutions.

    The aim of this thesis is to make ecosystem services in Knivsta municipality visible through the green structure plan and to analyze the ecological connectivity between the ecological structures using the ArcGIS-tool Matrixgreen. A literature study laid the foundation for further work and was followed by a workshop where important ecosystem services to the municipality of Knivsta were identified. Ecological profiles were created where 11 of the 18 prioritized ecosystem services were associated with specific biotopes which in turn could be linked to a biological species or species groups, called target species, with the specific biotope as possible habitat. The habitat preferences of the target species (size requirements and distribution patterns) worked as a framework for how to analyze the connectivity for each biotope. This was followed by gathering of maps and the making of ecological networks in Matrixgreen. The networks were analyzed with respect to position of the patches in the network (Betweenness Centrality analysis) and the overall connectivity in the municipality (Component analysis).

    Common to the four selected biotopes (wetland, grassland, coniferous and deciduous forest) is that they indirectly provide us with the prioritized supporting ecosystem services habitats and biodiversity. The prioritized ecosystem services water treatment, flow regulation and flood control were linked to the biotope wetlands and materials (ornamental) and pollination were linked to the biotope grasslands. The biotopes coniferous and deciduous forest could be linked to the prioritized ecosystem services food (domestic and wild animals, wild plants), raw materials (fiber), bio-energy and climate control. The network analyses show good connectivity for wetland areas and coniferous forest in the municipality. The total connectivity for grasslands and deciduous forest is limited. The analyzes also show that for each biotope a couple of areas are especially important for the overall connectivity. These areas have a high Betweenness Centrality value.

    The ecological profiles upon which the analyzes are based are theoretical profiles, no site visits or surveys have been done to investigate how reality matches theory. The constructed and analyzed networks in this thesis are therefore to be seen mainly as a guide to where in the municipality the selected ecosystem services are available. The networks do not constitute adequate habitats for the selected target species and no conclusions can be drawn as to where in the municipality a specific species exists or not. Biodiversity is an ecosystem service itself but also represents an insurance for the ecosystem that becomes more resilient, i.e. more stable and resilient to external shocks. Resilient ecosystems are essential for the ecosystem services that have been studied. Lack of connectivity in the landscape could lead to increased fragmentation and eventually risk biodiversity depletion.

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  • 30.
    Bonde, Carl
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Närsaltsdosering till luftad damm: en åtgärd för ökad TOC-reduktion hos Skoghalls Bruk luftade damm2006Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In the process of making carton boards into Skoghall Mill, are great quantities of water being contaminated. This water has to be treated before it is possible to release into the recipient, Kattfjorden. One of the contaminations that is important to extract from the wastewater, is organic carbon (measured as TOC-total organic carbon) because microbiological breakdown can lead to the bottom becomig free of oxygen.

    The wastewater treatment at Skoghall Mill is done through an external wastewater treatment that is located at the factory. The biological treatment (aerated lagoon) is a 140 000 m3 water pool with surface aerator, which is give oxygen to the water. In the lagoon live microorganisms who performs the biggest part of the TOC-reduction.

    One problem with the lagoon is that the treatment of TOC is considerably worse during wintertime than during summertime. The reduction is during wintertime only 40 %, while during summertime it is about 70-80 %. This seasonal variation can to a large extent be explained by, that the water temperature in the lagoon decreases wintertime. The low water temperature does that the biological activity in the lagoon is reduced, which reduces the TOC-reduction. A second reason can also be that the microorganisms do not have enough bioavailable nutrients that is needed for growth of a new biomass.

    In this thesis the need of nutrient has been examined. In two test pools, addings of nutrient were being done, to come to the conclusion of a good dosage of nutrient which would lead to a larger reduction of TOC, without enlarged quantities of nitrogen/phosphorus in the outgoing water. One of the test pools hold a summer temperature (30°C), and the other test pool hold a winter temperature (10°C). The test was performed this way to see if there would be any difference in the need of nutrient between summertime and wintertime.

    The most important conclusion was that a nutrient dosage to the Skoghall aerated lagoon, rise the TOC-reduction wintertime. It was also concluded that it was foremost the nitrogen that contributed to the raised TOC-reduction, and nitrogen is thereby considered to be the growth restraining element wintertime. It seemed like phosphorus had been overdosed during the tests, while enlarged halts of the substance could be seen in the outgoing water, and an optimal dosage of phosphorus could not be done. The recommendation that came as a results from the tests, was that during wintertime add nitrogen and phosphorus according to TOC:N:P-quota 100:0,75:0,10. To the summer pool was no considerable improvement of the TOC-reduction seen, as a result of the nutrient addings. It is also no reason to dosage nutrients in summertime.

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  • 31.
    Borg Berggren, Alma
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Dagvattenhantering på underbyggda gårdar inom kvartersmark2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    With the expansion and densification of cities, green areas are removed while the proportion of hard surfaces are increased. Rain and melt water are not allowed to infiltrate through the hard surfaces, and instead it runs off like stormwater. With this and the expected increase of precipitation due to climate changes, it is becoming increasingly important to plan for the disposal of stormwater in new urban areas. Several Swedish municipalities are today providing restrictions regarding the diversion of stormwater on private properties and requirements that need to be met before connection to the public water network. Meanwhile, densification means that builders today are often forced to build residential yards on underground garages. There was a need to clarify and investigate today's situation regarding stormwater treatment in combination with underground garages.The purpose of this thesis was to analyse today's state of knowledge about stormwater treatment on yards with underground garages and to investigate how different actors experience the requirements. Qualitative interviews with representatives from the three groups of actors, stormwater sewer operators, planning divisions and developers were conducted. The aim was also to design a tool for highlighting connections between stormwater management and other interests on private properties.This thesis was delimited to study green roofs, plant beds and detention tanks. Five interests were identified on yards with underground garages: landscape architecture, architecture, construction, management and HVAC. A tool was designed including the stormwater facilities containing four steps: Today’s and future construction, Stormwater requirements, Choice of facilities and Further recommendations or suggestions for corrections. Within the tool, four checklists were established to describe connections between stormwater treatment on yards with underground garages and the interests.The interview results show that several interviewees find it difficult to impose restrictions for stormwater management due to legal uncertainties. Meanwhile developers find following the restrictions can be difficult with yards with underground garages, mainly due to lack of space. The checklists are intended to serve as guiding points that should be taken into consideration in stormwater management on underground garages and to help balance different interests. The hope is that the checklists can contribute to an increased understanding of the relationships between stormwater management with underground garages and other interests. The results of the thesis show that interaction between the various interests is needed to create conditions for a good stormwater management and that communication about a joint purpose for the yard with an underground garage is important for maintaining the function of the yard.

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  • 32.
    Bosson, Emma
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Modellstudie av föroreningsretention i Bäckaslövs våtmark: Tillämpning av modellverktygen MIKE SHE WET och MIKE 212004Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    During the nineties, ecological handling of urban storm water became very popular in Sweden. Together with Chalmers University of Technology and two Swedish communities, DHI Water and Environment has been doing research of storm water ponds and constructed wetlands. This thesis work is a part of that research project. The work has been applied at the Bäckaslöv storm water treatment plant in Växjö, Sweden. The plant consists of one storm water pond and a downstream constructed wetland. Simulations in two different modelling programs, MIKE SHE WET and MIKE 21 have been performed. MIKE SHE WET has never been used in practical work. The purpose of the program is to describe chemical and biological processes in wetlands and how the plants affect the retention of nutrients in the water. Since the program never has been used before, the main work has been to test the model to investigate whether it fulfil its purpose or not. MIKE 21 has been used to describe how the geometry influences the retention of suspended material, nitrogen and phosphorus. MIKE 21 has also been used to study how the wetland works without the storm water pond. To be able to describe the natural processes going on in wetlands the program MIKE SHE WET has to be further developed. The work has yet resulted in a package of measures that can improve the model. Science is in need for a model like MIKE SHE WET. If the program will be edited it can contribute a lot to the research of wetlands and storm water treatment. The simulations in MIKE 21 show that today’s shape of the wetland is not most favourable. If the water was spread over a bigger area the retention of nitrogen, phosphorus and suspended material would increase.

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  • 33.
    Boyer, Linus
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Materials Science and Engineering, Applied Mechanics.
    DESIGNSTUDIE AV MEDIASTSYEM TILL STÅNGHÄRDLINJE UR ETT MILJÖPERSPEKTIV2021Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    The purpose of this thesis is to analyse if it would be possible to install a steel rod quench and tempering line with all attachments at the SSAB site in Virsbo. Thereto the thesis will overlook if the premises is suited for this production line and its gadgets, like a cooling basin and the relevant pumps, regarding the environmental laws put up by the government and EU. These laws will be compared to the environmental goals set by SSAB themselves and their pledge to reach the SDGs developed by UN.

    The fitting of the Q & T line was done together with the experienced engineers at SSAB after visiting and identifying the buildings characteristics. Inspirations for the new cooling basin were taken from a few of SSABs already existing production lines. To fit the cooling basin in the existing building another survey at the location in Virsbo had to be done due to poor drawings from all the redevelopments the premises has gone through over the years. 

    A proper investigation of the production building showed that it will be perfectly suited to accommodate the facility SSAB has in mind. The different water basins considered ended up with a simple solution where using an old storage will be rebuilt to contain the water.

    By doing a literature study reading about most of the laws and requirements that SSAB must follow it shows complicated systems. There are a few different decision-making bodies, and these have their own systems. SSAB themselves have decided to put more pressure on themselves by setting standards higher than the this. 

    SSAB has set a goal to produce steel without any carbon dioxide emissions by 2045. This project is called HYBRIT and is done by a joint venture company together with Vattenfall and LKAB. HYBRIT will be the solution for SSAB to manage all the laws and many of the SDGs. Together with the newest inventions in steel production and renewing old technology they can reach their highly set goals.

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  • 34.
    Bredberg, William
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    En utveckling av alternativa metoder för klassificering av avrinningsområden med avseende på bebyggelsetyp och anslutningsförhållanden2020Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Surfaces of varying permeability and different combinations of water pipelines within catchment areas result in different runoff coefficients. Classification of catchment areas with regards to building type and water pipeline connections are therefore commonly used in order to simplify runoff calculations. The work required to perform these classifications is often time consuming as it is performed manually. This master's thesis aims to make the task of classification less labour intensive.

    Three alternative methods for classification with regards to building type and one method for water pipeline connection were considered in this master's thesis. The first two building type classification methods were based on parallellepiped and maximum likelihood classification theory and required a choice of parameters and training data in order to perform classifications. The third method was based on a nearest neighbour algorithm and only required training data in the form of a number of previously classified areas. All three building type classification methods were evaluated against previously obtained classifications for catchment areas using confusion matrices. The method purposed for catchment area water pipeline connections was developed from a given number of predetermined conditions. That method did not have the same evaluation opportunities as no previously made classifications could be obtained. Instead, the method was validated by inspection of individual example areas.

    The method based on the nearest neighbour algorithm proved to perform very well, with a strength of agreement that was almost perfect under certain conditions. The performance of the method was however limited by city formation and area distribution. Hence, future usage of the method require an understanding of how the algorithm performs the classifications and under what circumstances the method may or may not produce sufficient results. All other methods purposed for building type classification produced inferior results with the parameters that were tested. The water pipeline connection classification method followed the outlined conditions and seemed to perform well. It is however subject to data limitations and the method would have to be validated in additional cities on several data sets in order to provide a better basis for evaluation.

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  • 35.
    Broström, Sabina
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Emilson, Adrian
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Ivarsson, Adam
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    von Krusenstierna, Isac
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Welin, Emma
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Åberg, Olivia
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Lokalisering av ovidkommande vatten i Örbyhus2022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Detta projekt genomfördes på uppdrag av TEMAB tillsammans med STUNS Energy. Under ett snösmältningsdygn i Örbyhus har det uppstått problem eftersom vatten som pumpats till Tierps reningsverk är i sådana stora volymer att reningsverket inte har tillräckligt hög kapacitet. Skillnaden i mängd vatten mellan ett torrt sommardygn och ett snösmältningsdygn är mycket stort och tyder på att vatten läcker in. Den stora mängden vatten tillför problem med rening av vattnet. Detta eftersom både försämrad rening av vatten och att orenat vatten släpps ut till naturen när avloppsystemets kapacitet överskrids. 

    Syftet med rapporten var att fokusera på vart det ovidkommande vattnet tar sig in i spillvattennätet samt besvara följande frågeställningar: (1) Vilka typer av ovidkommande vatten är det som kommer in i spillvattennätet? (2) Varierar flödet för huvudpumpstationen under året? (3) Vilka ledningssträckor kan vara rimliga källor till ovidkommande vatten? (4) Vilka lösningar finns det för att minska det ovidkommande vattnet? 

    För att besvara detta användes en metod med olika delar. En del där data givet av TEMAB analyserades för att avgränsa områden att fokusera på samt identifiera utsträckningen av problematiken. Ett studiebesök skedde under dagtid i Örbyhus, vilket inkluderande en intervju med personalen ansvariga för ledningsnätet. Metoden bestod även av en nattlig undersökning i Örbyhus för att leta efter synliga läckor och förändringar i vattenflödet. Slutligen utfördes en litteraturstudie för att kunna ge råd till uppdragsgivaren om åtgärder som kan minska problematiken med ovidkommande vatten. 

    Vid jämförelse av grafer innehållande nederbörd och pumpad mängd vatten ut från huvudpumpstationen är det tydligt att vattenflödet ökar vid nederbörd under båda tidsperioderna som undersöktes. Vid torrperiod efter nederbörd avklingar vattenflödet från huvudpumpstationen sakta. I resultatet avlästes tydliga variationer i den pumpade mängden från huvudpumpstationen under fem olika år. En trend är att den pumpade mängden i början och slutet av året är större än värdet under sommaren, men undantag finns. 

    Från den nattliga undersökningen i Örbyhus skapades kartor över flödesstorlekar i olika brunnar vid olika pumpstationer i tätorten. Från dessa kan skillnader på flödet upptäckas mellan olika brunnar och därmed se inläckage av ovidkommande vatten. Vissa skillnader mellan brunnar var väldigt tydliga medan andra följde en mer gradvis skala eller hade inga förändringar alls mellan punkterna. Utöver detta visade litteraturstudien att den mest framgångsrika åtgärden var återkoppling av felkopplade takytor. Att renovera ledningar utan att renovera brunnar ansågs misslyckat och detta har skett i hög grad i Örbyhus. Att fördröja dagvatten kan även minska det ovidkommande vattnet. 

    Slutsatsen från rapporten var följande: (1) Från resultatet av dataanalysen kunde slutsatsen dras att den pumpade mängden för alla pumparna förutom Persbylånga AP, påverkas tydligt av nederbörd i form av indirekt nederbördspåverkan. Ledningarna till Gyllbyvägens pumpstation påvisade även problematik med läck- och dräneringsvatten och även i ledningarna till Bruksvägens pumpstation fanns flertalet vattenfyllda brunnar. (2) En tydlig trend i variationen under åren syntes eftersom den pumpade vattenmängden från huvudpumpstationen, Örbyhus APS, ofta nådde ett större värde i början på året. Den pumpade mängden minskar under sommaren för att sedan öka när året börjar närmar sig sitt slut. (3) I Gyllbyvägen påvisades flera ledningssträckor som rimliga källor till inläckage. (4) Flera åtgärder finns, även om kostnadseffektivitet inte kunde analyseras eftersom det inte fanns gott om information var gällande hur dyra åtgärderna är. 

  • 36.
    Burström, Johanna
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences. 199309262047.
    Sustainability assessment of potential wastewater treatment techniques in Tupiza, Bolivia2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Aiming for sustainable sanitation systems can provide benefits among a vast range of Sustainable Development Goals. In this study the sustainability of potential options for renovating or upgrading thewastewater treatment plant in Tupiza, a rapidly growing city in theSouthern highlands of Bolivia, was evaluated. The local context was characterized by increasing issues of flooding which in recent years has destroyed important wastewater treatment infrastructure and polluted sources of water for several downstream communities. Three system options consisting of different treatment technologies were evaluated against four criteria of sustainability; health,technical, environmental and financial and institutional. A "conventional" option consisting of waste stabilization ponds was compared against two more options with added steps of treatment, such as constructed wetlands, anaerobic reactors and alkaline and ammonia treatment of sludge. Social acceptance and demand of reuse of treated wastewater and sludge in agriculture was evaluated using qualitative research analysis.

    Results indicate that the systems with added treatment steps could help improve several areas of sustainability such as risks of disease transmission, space efficiency, treatment capacity and efficiency as well as enable safe reuse of sludge and wastewater in agriculture. Implementation of funding mechanisms covering the entire sanitation service chain as well as flood mitigation measures resulted essential in ensuring the long-term functionality of such improvements. This project was intended as a pre-study and identified several areas of future research including additional evaluation of nutrient content in effluent, investigation of a possible certification process for recycled byproducts from the wastewater treatment plant, risk assessment of floods of different magnitudes, evaluation of the long-term economic impact of having improved systems and evaluationof local institutional capacity surrounding the sanitation service chain in Tupiza.

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  • 37.
    Bydell, Sofie
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Automatic control.
    Extension of the Benchmark Simulation Model no. 2 with a model for chemical precipitation of phosphorus2013Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    At present, there are more than 2000 wastewater treatments plants (WWTPs) in Sweden. Emissions of nitrogen and phosphorus from these, do contribute to the eutrophication of the Baltic Sea and watercourses on a daily basis. To reduce emissions of phosphorus, the Swedish approach has for the last 50 years been to use chemical precipitation.

    Today, software is used to test and evaluate different strategies in WWTPs, this in order to improve the operation and get a holistic view over the process. One model that can be used to achieve a holistic view is the Benchmark Simulation Model No. 2 (BSM2). In order to get a software like BSM2 to best mirror the reality, it is important that the model well describes the actual process. Today, BSM2 does not take the load of phosphorus into account, which, if it was included in the model, would describe the process better.

    In this master thesis, the author has investigated the possibility of extending the BSM2 model, to include phosphorus and chemical precipitation. Thereafter the results from simulations in BSM2 were compared with measurements from Henriksdals WWTP in Stockholm.

    The results showed that a model, after some simplifications, for phosphorus and chemical precipitation could be included in BSM2. The model uses primary precipitation. Precipitation chemical was added with assistance of a PI controller. Generally the results showed that the model had potential to describe the total flow of phosphorus in the WWTP. In measurements from Henriksdal the average total phosphorus effluent from primary and secondary sedimentation were 3.97 and 0.43 mg/l, respectively. From a steady state simulation in BSM2 the values were ​​4.26 and 0.44 mg/l and the average values ​​of a dynamic simulation 3.96 and 0.46 mg/l.

    Although the average values of total phosphorus matches quite well, it was found difficult to simulate the different fractions of phosphorus effluent from the secondary sedimentation. In order to better evaluate the results and how the simplifications of the model affects them, more measurements need to be done and a comparison with the results received from the BSM2 needs to be carried out. Also an adjustment of parameters in BSM2 must be done, this to achieve a better compliance with the given plant.

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    SofieBydell
  • 38. Bäcke, Maja
    et al.
    Norin, Kajsa
    Guterstam, Isa
    Strand, Hanna
    Hemlin, Bellisa
    Isitman, Per
    Utformning av filter för dagvattenbrunnar i Uppsala innerstad2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Det vatten som hamnar i centrala Uppsalas dagvattenbrunnar rinner rakt ut i Fyrisån utan någon form av rening. Detta blir ett miljöproblem när cigarettfimpar och annat skräp hamnar i brunnarna. Denna studie syftar till att åtgärda problematiken med att cigaretter hamnar i Fyrisån. Studien genomfördes genom en teknisk lösning som togs fram utifrån att gallret på dagvattenbrunnarna inte ska behövas lyftas av med jämna mellanrum eftersom de är tunga men att de även fångar upp cigarettfimpar utan att vattenflödet ska hindras. Resultatet blev tre olika 3D-printade filterkonstruktioner i form av korgar som förs ned i hålen på brunnsgallret. För att förhindra översvämning om filtren blir för fulla placerades öppningar längst upp i respektive filtret så att vattnet alltid har ett utlopp. Vid test framgick att ett skräpfyllt filter inte begränsar flödeshastigheten mer än att de borde klara även stora nederbördsmängder. Den slutliga filterprototypen släpper igenom ca 18% av de cigarettfimpar som testades. Slutsatsen är att ett filter är en potentiell lösning på problematiken kring cigarettfimpar i Fyrisån. Dock krävs mer produktutveckling och testning av filtret innan det kan bli en fullt komplett lösning.

  • 39.
    Bäcklund, Annika
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Fotogrammetrisk analys av kornstorleksfördelningeni erosionsskydd vid kraftverksdammar2014Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This master thesis was made to investigate the possibilities of using the Matlab-basedsoftware Basegrain to determine grain size distributions of erosion protections onhydropower dams. Basegrain is a photogrammetric tool developed to generate grainsize distributions and other information about coarse flood sediments by analyzing adigital photo of the stone bed. The investigation was made by validating the ability forBasegrain to assess grain size distributions of various materials smaller than the blocksused in an erosion protection by comparing sieving results or manual measurementswith the results obtained by the program. A statistical comparison was then made bycomparing the results from sieving and the program. The possibilities of using thesame method on existing hydropower dams were then investigated by determiningwhether the method was practically viable or not.The results showed that Basegrain generated grain size distributions for coarse gravelthat were very close to the sieving results. It also provided grain size distributions forlarger fractions of stones quite close to the results made by measuring the diameterof the stones by hand. The results also showed it was possible to use the samemethod on existing erosion protections on hydropower dams and obtain grain sizedistributions.

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  • 40.
    Calestam, Karl-Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Bestämning av vattendelare i urban miljö: Metod för avgränsning av avrinningsområden i ArcGIS utgående från dagvattensystemet2013Independent thesis Basic level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Growing populations result in expanding cities. An increase in the amount of impervious surfaces in the area will follow and thereby generate more storm water. The capacity of the drainage system can be evaluated using hydraulic modelling. The model highly depends on the catchment areas, which will determine the water volume each pipe section receive. Watershed delineation is usually done based on the topography. However, if a storm water drainage system is present, it may route the water in a different direction than the slope indicates. ArcHydro Tools is an extension to ArcMap and is commonly used to delineate catchment areas. The method heavily relies on topography during this process. A function has been developed during the course of this project to allow for the drainage system to be the primary source of information for watershed delineation.

    This function made sure that outlets in the model were to be evaluated as such, even if they happen to be located in the middle of the area of interest. The water is therefore not necessarily routed to the edge of the elevation model, but can be allowed to stay at the appropriate position. In order to do this, the drainage system was represented as a stream network.

    The new method was applied to test data supplied by Lidingö city, Stockholm, Sweden, and included elevation data and information about the drainage system. The result implies that it is indeed possible to use the drainage system as a base for delineation of catchment areas. A more efficient method of calculating catchment areas will reduce the required amount of manual processing, thereby saving time and resources. Another function, for finishing up the resulting catchment areas, is proposed but not fully implemented. The whole process was used to delineate catchment areas for Molkom, County of Värmland, Sweden. The resulting watersheds were later successfully used for modelling the storm water drains in the area. 

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  • 41.
    Carlsson, Lisa
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Tillförlitligheten i beräknade dimensionerande flöden i två mindre vattendrag med trånga sektioner2013Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In Sweden there is currently an accepted method for determining the design floods for dams which is described in The Swedish Design Flood Guidelines. The theoretical calculations of the design floods for dams associated with Flood Design Category I are based on the HBV model, a conceptual hydrological model that describes the interaction between the meteorological and hydrological conditions within a basin. Conceptual hydrological models are based on the water balance and are used to determine runoff to streams, lakes or other bodies of water. Conceptual hydrological models do not take explicit account for the geometry of the watercourse. Narrow sections in natural streams may prevent water flow and cause impoundment upstream from the narrow section. Following that, a part of the flow peak can be retained in the terrain and thereby attenuated and delayed. Hydraulic models describe the flow of water through the watercourse. High resolution elevation data is the foundation of a hydraulic model and hydraulic models thus take into account the basin topography as well as the watercourse bathymetry.

    The objective of this study was to analyze the reliability of design floods that have been determined according to The Swedish Design Flood Guidelines. By establishing hydraulic models of two specific streams affected by narrow sections it could be examined whether the narrow sections cause flow attenuation and whether the flow attenuation depends on the size of the water flow. The areas which were the subject of this study were a subsection of River Lagan and part of River Bolmån, which is River Lagan’s largest tributary.

    The results of the hydraulic model simulations showed that the flow peaks were attenuated and that it was the narrow sections that caused the main flow attenuation. Furthermore, the results showed that the relative attenuation depends on the size of the inflow in the hydraulic models. The relative attenuation of the design floods was 1.2 % and 2.0 % at River Lagan and 6.7 % at River Bolmån. The relative attenuation of the design flood was thus marginal at River Lagan. The fact that the design floods nevertheless were attenuated at both areas which were the subject of this study should be reason enough to review the method for the determination of design floods for dams associated with Flood Design Category I and examine whether it is possible to include hydraulic modeling in today’s conventional calculation methodology.

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  • 42.
    Carlsson, Magnus
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Identifiering av parametrar för tillståndsbedömning av en vattenkraftstation2004Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The report begins with a general inventory of possible technical faults in a hydropower plant and of possible fault indicating measurements. Then an investigation is made concerning a few different faults. Based on this investigation a choice on seal box condition and water leakage is made as problem for a more thorough examination, in which it is concluded that the turbine water leakage is larger when the turbine is put into operation. The examination ultimately results in a computer alarm for faults related to the seal box. Finally a few things are mentioned about flow measurement and pressure measurement in relation to the project as a whole.

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    FULLTEXT01
  • 43.
    Cedergren, Andrea
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Prognostisering av dimensionerande grundvattennivå: En fallstudie av Chalmersmodellen och hur referensrör med olika hydrogeologiska egenskaper påverkar modellens tillförlitlighet2022Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Groundwater can potentially have a great impact on both constructions and the surrounding areas, and high groundwater levels can involve risks such as uplifting forces and landslide. Due to these risks it is important to predict and estimate the probability of extreme groundwater levels. However, when the necessary long term measurements are not available alternative methods are needed, like the Chalmers model. The Chalmers model is used for calculating extreme ground water levels, by combining a short measurement series from an observation well with the data from a reference well. For the results to be as accurate as possible, the two wells must share similar characteristics.

    The aim of this study is to investigate the Chalmers model when predicting the groundwater level for a specific return period. Focus will be on how the choice of different reference wells, with different characteristics, will influence the accuracy of the model.

     A case study will be conducted on two station sites (Sockenplan and Station Sofia) for the extension of the metro in the southern part of Stockholm, Sweden, upon which the Chalmer model will be implemented. The different characteristics of the obeservation and reference wells are tested to evaluate the accuracy of the model. The accuracy will be evaluated by using extreme value analysis as an alternative calculation model, assumed to be more precise, and compare the difference in extreme groundwater levels. The measurements used as reference in the Chalmers model are public data from The Geological Survey of Sweden, SGU, for groundwater levels. Data processing and calculations are performed in python.

    This study highlights the difficulties in determining the accuracy of the Chalmers model when predicting extreme groundwater levels, and no specific expected accuracy has been determined. Generally, the model appears to underestimate extreme grounwater levels. Furthermore, if the observation well and reference well are located by a confined aquifer and between inflow- and outflow areas, a higher precision can be expected. The uncertainty of the model increases with an unconfined aquifer. The results also imply that if the reference well and the observation well are selected based on similar hydrogeological characteristics, a covariation of groundwater levels over time and between highest and lowest level, a higher accuracy can be expected.

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  • 44.
    Cronander, Joel
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Återskapande av naturliga trösklar i mindre vattendrag och våtmarker: Modellutveckling för simulering av förändradeflödesregimer2017Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In the late 20th century a decrease in coastal predatory fish in the Baltic Sea has been observed. It has been suggested that exploitation of the fish’s spawning habitats, mainly through draining of coastal wetlands, was one reason for the fish decline. To recreate spawn and growth areas, natural thresholds can be installed in trenches draining coastal wetlands. To quantify the effects of a natural threshold on water discharge in the drainage area under various water flow regimes modeling is needed.In this study, a hydraulic model was developed to estimate the effect of changing water discharges of three wetlands when natural thresholds are implemented, i.e. Maren, Hyllekärr and Brokhål, located on northern Öland. The model was run under different water flow regimes. Through an observed strong relation between catchment area and discharge, extreme discharge situations could be simulated. A method for investigating the effects of natural thresholds on upstream flow regimes has been developed with hydraulic modeling in HEC-RAS. To validate the model results, a comparison with empirical data during the spring flood 2017 was made.Model simulations showed that only water discharges in Brokhål behaved as expected, Maren behaved as expected for large flows and results for Hyllekärr were considered not being reliable. Validation showed that the elevation model for topography and bathymetry deviated from reality in all three wetlands. The elevation model has been identified as the single largest source of error in the water discharge model.From the model results, it is concluded that natural thresholds have none, or very minor effects on the upstream water flow regimes. It should however be emphasized that the model has major limitations, in particular the elevation model’s resolution. It is highly recommended to further develop the elevation model before further simulations on water discharges are made. The results from this study should only be considered as a first approximation where more detailed studies are needed to confirm that natural thresholds won’t result in major changes in upstream water flows.

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  • 45. Dahlbäck, Niklas
    et al.
    Norrlund, Per
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Examples of Benefits from Efficiency Evaluation Using Comparative Tests2014In: 10th International Conference on Hydraulic Efficiency Measurements 2014-09-16 - 19, Itajubá, Brazil, 2014Conference paper (Refereed)
    Abstract [en]

    Traditionally, most field efficiency measurements are made to verify guarantees for a new project, which have led to that this issue is well covered by standardization guidelines. There are however several other situations where information from field efficiency measurements contributes with value. Depending on issue and site characteristics, there are several feasible options, that are not described in current standards of primary methods.

    A comparative test is here defined as a test where efficiency is evaluated at the same flow conditions but with modified or changed turbine or water conduits. At an efficiency evaluation of a comparative test, many systematic uncertainties will cancel, and the overall evaluation of uncertainty will be at a very useful level. 

    This paper presents experiences of the hydropower producer Vattenfall, from several efficiency tests, where different types of comparative tests settings have been used.

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    Dahlback_Norrlund_IGHEM2014
  • 46.
    Dahllöf, Karin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Trycksatt avloppssystem och självfallssystem i Fredrikstad kommun. En jämförande fallstudie.2014Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    As a result of stricter treatment requirements and city expantion the length of the sewer network is steadily increasing. To drain wastewater by gravity requires a continuous slope which often results in great excavation - a very costly part in the process. An advantageous alternative could be a pressurized sewer system, which has been a useful complement to traditional gravity systems in hilly or rocky areas since the 70’s. Even though pressurized sewer systems lately have tended to be more frequently used outside their common application area due to stricter requirements on treatment and cost-efficiency, gravity systems are still the most common sewer system in urban areas. Concerning this, it would be intresting to investigate which of the two systems that suites a residental area on the outskirts of a city center best, since the area is outside the traditional usage of the two established systems. In addition it would be interesting for the wastewater industry in general to investigate how the two systems compare. 

    For this reason the aim of this master thesis was to compare pressure sewer systems with gravity systems on the basis of economy, environment and capacity. In addition, it was examined whether any general conclusions could be determined from the case study. The survey was based on a residental area in the outskirts of Fredrikstad city center, recently designed with a gravity system. A theoretical pressure sewer system was designed. Economy was evaluated based on the operating and maintenance costs and basic and reinvestment costs. The capacity was compared numerically and through design templates. As for the environmental comparison, an evaluation was done on the basis of reports from the Swedish Water & Wastewater Association and Norwegian Water BA.

    An expansion to double the number of real properties was planned for the area of study, which proved to be crucial to the financial results. The gravity system was most appropriate from an economic standpoint and the vital factor was the high investment and operating costs for the pumping units. Even from an environmental point of view, the gravity system was maginally better. Given that the risk effects are not ranked relative to each other. In terms of capacity the gravity system was dimensioned for almost twice the flow compared to the pressure sewer systems, which gave the pressure sewer system a more adusted capacity. The result indicated that the pressure sewer system is favorable in densely built flexible areas.

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  • 47.
    Dahlström, Julia
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Avloppsrening från småskalig processindustri2020Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Small-scale process industries are small, sometimes locally or artisanal, industries that produces their product through processing raw materials by using automated processes. Large volumes of wastewater effluent are produced by doing this, and this wastewater is characterized by high organic load and nutrients which must be treated in a sustainable way to not be harmful to humans nor the environment.

    This study evaluated industrial wastewater treatment from small-scale slaughterhouses, dairies and breweries, including wastewater characteristics of these types of process industries in Sweden today. The study also included an evaluation of decentralized wastewater treatment systems for small-scale industrial wastewater treatment and what the Swedish market can provide regarding small-scale industrial wastewater treatments. Different methods were used to reach this goal; a literature study regarding wastewater characteristics and treatment of industrial wastewater and decentralized wastewater treatment systems, interviews, and surveys of Swedish small-scale process industries, and finally interviews with manufacturers of decentralized wastewater treatment systems.

    The result showed that wastewater characteristics was not accessible from most of the Swedish small-scale process industries. They mostly do not analyze their wastewater neither before nor after wastewater treatment. Furthermore, it was described that highpriority wastewater characteristics for treatment according to the literature was BOD, COD, suspended solids, nitrogen, phosphorus, and pH. Variations of these characteristics is common both between different types of process industries and in the same type of industry. These variations are challenging in regard to finding suitable wastewater treatment techniques that is adequate in every situation.

    Wastewater treatment systems used today are mostly local at the site, it is around a third that have connection to municipal wastewater facilities. The most common local wastewater treatment for small process industries (less than 100 population equivalents) is decentralized wastewater treatment systems according to the interviews and surveys. Other wastewater treatments such as dung pits, wastewater treatment plants and biogas plants were also used for larger process industries.

    Decentralized wastewater treatment systems for industrial wastewater treatment and adapted small-scale industrial wastewater treatments can be found to some extent on the Swedish market today, but there are still some challenges to provide small-scale industrial wastewater treatment for every type of process industry. Solutions to level out intense wastewater flows and capacity to receive high effluent loads need to be further developed.

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  • 48.
    Davtalab, Rahman
    et al.
    Graduate Student, Dept. of Civil, Environmental and Construction Engineering, Univ. of Central Florida, Orlando, FL 32816; Dept. of Remote Sensing and GIS, Tarbiat Modares Univ., Tehran, Iran..
    Mirchi, Ali
    Research Assistant Professor, Dept. of Civil Engineering and Center for Environmental Resource Management, Univ. of Texas at El Paso, 500 W University Ave., El Paso, TX 79968 (corresponding author)..
    Khatami, Sina
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. University of Melbourne.
    Gyawali, Rabi
    Research Agriculture Engineer, Grazinglands Research Laboratory, Agriculture Research Service, U.S. Dept. of Agriculture, El Reno, OK 73036..
    Massah, Alireza
    Associate Professor, Dept. of Irrigation and Drainage Engineering, College of Abureyhan, Univ. of Tehran, Iran..
    Farajzadeh, Manuchehr
    Professor, Dept. of Remote Sensing and GIS, Tarbiat Modares Univ., Tehran, Iran..
    Madani, Kaveh
    Reader, Centre for Environmental Policy, Imperial College London, London SW7 2AZ, U.K.; Dept. of Physical Geography, Stockholm Univ., Stockholm, Sweden..
    Improving Continuous Hydrologic Modeling of Data-Poor River Basins Using Hydrologic Engineering Center’s Hydrologic Modeling System: Case Study of Karkheh River Basin2017In: Journal of hydrologic engineering, ISSN 1084-0699, E-ISSN 1943-5584, Vol. 22, no 8Article in journal (Refereed)
  • 49.
    Ddiba, Daniel
    et al.
    KTH Royal Inst Technol, Dept Sustainable Dev Environm Sci & Engn, Teknikringen 10B, SE-10044 Stockholm, Sweden.;Uppsala Univ, Dept Womens & Childrens Hlth, Dag Hammarskjoldsvag 14B, S-75237 Uppsala, Sweden.
    Andersson, Kim
    Stockholm Environm Inst, Linnegatan 87D,Box 24218, S-10451 Stockholm, Sweden.
    Dickin, Sarah
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health. Stockholm Environm Inst, Linnegatan 87D,Box 24218, S-10451 Stockholm, Sweden.
    Ekener, Elisabeth
    KTH Royal Inst Technol, Dept Sustainable Dev Environm Sci & Engn, Teknikringen 10B, SE-10044 Stockholm, Sweden.
    Finnveden, Goran
    KTH Royal Inst Technol, Dept Sustainable Dev Environm Sci & Engn, Teknikringen 10B, SE-10044 Stockholm, Sweden.;Luxembourg Inst Sci & Technol Environm Sustainabil, Belvaux, Luxembourg.
    A review of how decision support tools address resource recovery in sanitation systems2023In: Journal of Environmental Management, ISSN 0301-4797, E-ISSN 1095-8630, Vol. 342, article id 118365Article, review/survey (Refereed)
    Abstract [en]

    Globally, there is increasing interest in recovering resources from sanitation systems. However, the process of planning and implementing circular sanitation is complex and can necessitate software-based tools to support decision-making. In this paper, we review 24 decision support software tools used for sanitation planning, to generate insights into how they address resource recovery across the sanitation chain. The findings reveal that the tools can address many planning issues around resource recovery in sanitation including analysis of material flows, integrating resource recovery technologies and products in the design of sanitation systems, and assessing the sustainability implications of resource recovery. The results and recommendations presented here can guide users in the choice of different tools depending on, for example, what kind of tool features and functions the user is interested in as well as the elements of the planning process and the sanitation service chain that are in focus. However, some issues are not adequately covered and need improvements in the available tools including quantifying the demand for and value of resource recovery products, addressing retrofitting of existing sanitation infrastructure for resource recovery and assessing social impacts of resource recovery from a life cycle perspective. While there is scope to develop new tools or to modify existing ones to cover these gaps, communication efforts are needed to create awareness about existing tools, their functions and how they address resource recovery. It is also important to further integrate the available tools into infrastructure planning and programming processes by e.g. customizing to relevant planning regimes and procedures, to move them beyond research and pilots into practice, and hopefully contribute towards more circular sanitation systems.

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    fulltext
  • 50. Di Baldassarre, Giuliano
    Floods in a Changing Climate: Inundation Modelling2012Book (Other academic)
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