The objective of this study is to compare Large-Scale Particle Image Velocimetry (LSPIV) to conventional methods for measuring discharge. Furthermore, to use the discharge data to create a rating curve at Islandsfallet in Uppsala. To measure discharge, on-site measurements have conventionally been done. Particle tracking allows flow velocimetry measurements without contact with the water. LSPIV works by measuring displacement of tracers through analysing image sequences. Using the free software Fudaa-LSPIV, flow velocity was measured and referenced to ADCP. The ADCP data were additionally used to construct the rating curve allowing to predict the water level/discharge correlation. Particle tracking was found to hold great potential in the Fyris river, and the possibility for setting up LSPIV for continuous discharge measurements should be investigated going forward. Constructing the new rating curve with discharge measurements from ADCP implied the current rating curve not being sufficient by underestimating the discharge levels necessary for a raise in water level implying the need for an updated rating curve. Concluding, does the LSPIV show promising result compared to the ADCP and the rating curve points out a big discrepancy, in higher discharge, between the new and the old rating curve. The rating curve would however need discharge data points in a greater range. / Syftet med detta arbete var att jämföra partikelspårning med mer traditionella metoder för att mäta vattenflöde. Vidare, att använda data för vattenflöde till att skapa en avbördningskurva vid Islandsfallet i Uppsala. För att mäta avrinning, är fältmätningar det konventionella sättet. Partikelspårning tillåter flödesmätningar utan krav på närvarande tekniker på plats. LSPIV fungerar genom att mäta förflyttning av spårelement på ytan genom att analysera sekvenser. Genom att använda gratisprogrammet FudaaLSPIV, mättes vattenflöde och data från ADCP användes som referensdata. Data från ADCP metoden användes också för att skapa en avbördningskurva som tillåter projicering och korrelation av vattennivå samt vattenflöde. Partikelspårning visade sig ha stor potential för Fyrisån och möjligheten att använda LSPIV för kontinuerliga mätningar bör undersökas vidare. Skapandet av den nya avbördningskurvan visade att den nuvarande avbördningskurvan underskattar vattenflödet mot vattennivån och vidare mätningar är nödvändiga för att utveckla avbördningskurvan vidare. Sammanfattningsvis visar LSPIV på positiva resultat i jämförelse med ADCP och avbördningskurvan visar på en stor diskrepans, i högre flöden, mellan den nya och den gamla avbördningskurvan. Avbördningskurvan skulle behöva ett större antal datapunkter för större flödesintervall.

Turbulence is important since it affects the exchange of momentum, heat, and trace gases between the atmosphere and the ocean. However, measuring oceanic turbulence is not straightforward and that is why parameterizations that describe turbulence events are important. In this thesis turbulence data from the Baltic Sea is investigated and compared to already existing parameterizations.  The thesis considers turbulence in the ocean surface boundary layer (OSBL) and how atmospheric parameters act as driving mechanisms. Turbulence creates mixing that enables the dispersion of various particles and a more efficient gas transfer at the air-sea interface. This thesis aimed to investigate the connection between the drivers of oceanic turbulence, wind, waves, and buoyancy fluxes and how they contribute to the formation of enhanced turbulence events. To investigate this, turbulence data from the Baltic Sea from June to August 2020, collected by an ADCP (Acoustic Doppler Current Profiler), was used to find connections to meteorological data during the same time period. Since turbulence is difficult to measure, three already existing parameterizations were compared to the observed turbulence to investigate their performance. The results showed that conditions with higher wind speeds with corresponding waves gave a better correlation between surface turbulence and wind and waves. The parameterization that included wind and waves gave results closest to the observed turbulence at the surfaces, compared to when only wind shear was included. It was also detected that the parameterized turbulence was in almost all cases under-predicted in comparison to the observed turbulence. To clarify why this is the case, a more detailed analysis would be needed to find what parameters are missing for better predictions of the surface turbulence.

Rapporten ämnar utvärdera potentiella begränsningar inom vattenkraftsindustrin i relation till högvattenföring under ett skiftande klimat. Detta görs genom en litteraturstudie gällande lagar och föreskrifter, samt med en modellering av de flödesförändringar som uppstår i den övre delen av Pite älv i norra Sverige som en konsekvens av ett skiftande klimat. Modelleringen görs med HBV-96 och fyra olika scenarion med ett modellerat referensflöde. Vattenkraftsindustrin är för det mesta reglerad privat med egenkontroller, med krav för inrapportering till länsstyrelsen för de dammar vars bristning kan orsaka stor skada.Modelleringen och scenarierna fann en tendens till svagare vårfloder som en konsekvens av ökad medeltemperatur. Ökningen i medeltemperatur har inga observerade direkta effekter på vattenföring under sensommar och höst, men potential för indirekt påverkan finns. Om nederbörd ökar, som förväntat, kommer vi se en ökning i volym av vatten i älven. Resultatet ser ingen krav för anpassning till större flöden i en snar framtid då de kraftigaste flödena under våren kommer minska, däremot lär ett skifte i beteendet av den årliga vattenföringen ske med ett flöde som är mer beroende av nederbörd istället för snösmältning. Detta medför en uppmaning till förändring i korttidsstrategi med hjälp av större marginal i dammens vattenhöjd tillsammans med modellering och väderprognoser, främst under sensommar och höst. / The focus of this paper is on the changing conditions in the hydrological flow of the upper half of Pite älv in Northern Sweden as a consequence of the changes that comes with global warming. This was done by modelling the water flow with the HBV-96 model as its basis which then ran four different scenarios based on predictions for how the climate will have changed by year 2100. The paper also discusses the limitations with this applied method. The study found that in the case of dam failure the owner is responsible for the damages, furthermore the owner is recommended to model potential limitations and dangers, but there is no requirement for this. State actors which oversees and keep tabs on all issues regarding water safety exists for every county, though their involvement appear somewhat limited and does not extend to close monitoring of the dams. The study found a decrease in the volume of spring floods due to a decrease in snow storage because of increasing temperatures. Furthermore, the increase in mean temperature has no notable direct effect on the autumn precipitation and water flow but potential indirect consequences are discussed. If precipitation were to increase during autumn as predicted, we will see an increase in both the peaks and amount of autumn high flows. However, these peaks will be lower than the current spring floods. We conclude that in large there is no reason for large changes in how the hydro industry conducts itself in relation to regulation of water flow in terms of infrastructure. There is however, possibly a need to increase the margin which one can store water in dams during longer periods with high flow together with more reliance on meteorological short term analysis to be better prepared for more sudden high flows.

This thesis focused on testing the suitability of reactive filter media used for phosphorus (P) removal from wastewater as fertilizers, thus recycling P to agriculture. The work compared the P sorption capacity of several materials in order to assess their suitability as a source of P for plants. The selected materials (Filtra P, Polonite and wollastonite) were saturated with P and used as soil amendments in a pot experiment. The amendments tended to improve the yield of barley and ryegrass compared with no P addition. The amendments also increased soil pH, P availability and cation exchange capacity in the studied soils. The substrates studied here can be of particular interest for acid soils. Of the materials studied, Polonite appears to be the most suitable substrate for the recycling of P from wastewater to agriculture / QC 20101103

During all periods of human history collecting rainwater has been a useful way to get access to water. With ongoing climate change the guarantee of having water available is changing. With increasing heat the weather behaviour is shifting leading to more intense weather, both extremer rain periods and droughts. Due to this situation collecting rainwater is getting more attention. Rainwater can be used for various water needs depending on how much treatment it has been going through. With a local recirculation of rainwater the stress on water sources and demand against the waterworks can decrease.  The aim of this master thesis was to develop a dimensioning tool, a recirculation map. A tool to quickly and easily analyse the potential of rainwater collection and rainwater reuse. With the flexibility to compare different scenarios, users can evaluate their options on rainwater collecting system.  The recirculation map contains two parts. An interactive map that gives the user a quick way to get access to the rooftop surface area in which the collection of rainwater occurs. The other part is a dimensioning tool to quickly analyse the potential in collecting rainwater in relation to various water needs. Input parameters like rooftop area, runoff coefficient, rainwater demand per day and water magazine size were used for the dimensioning tool to analyse potential in collecting rainwater. The recirculation map ended up fulfilling all the demands and goals that were set at the beginning of the project.

Studien undersöker hur organiska restprodukter kan användas som kolkällor för denitrifikation i vattenreningsverk för att främja hållbarhet och effektivitet. Genom litteraturstudier utvärderades olika organiska restprodukters potential med avseende på denitrifikationseffektivitet, tillgänglighet & kostnad, samt miljöpåverkan. Resultaten visar att biologiskt nedbrytbara polymerer som poly(3-hydroxybutyrat-co-3- hydroxyvalerat), PLA och fermenterad matavfallsvätska är kostnadseffektiva och effektiva för denitrifikation. Mikroalgbiomassa, även om den inte är en restprodukt, visar också stor potential för kväveavlägsnande. Diskussionen fokuserar på behovet av noggrann övervakning och förbehandling för att minimera negativa effekter på denitrifikationsprocessen och främja användningen av dessa hållbara alternativ för avloppsvattenbehandling och miljöskydd. / The study investigates how organic residues can be used as carbon sources for denitrification in water treatment plants to promote sustainability and efficiency. Through literature studies, the potential of different organic residues was evaluated with respect to denitrification efficiency, availability & cost, and environmental impact. The results show that biodegradable polymers such as poly(3-hydroxybutyrate-co-3- hydroxyvalerate), PLA and food waste fermentation broth could be a cost-effective and efficient for denitrification. Microalgal biomass, although not a residual product, also shows great potential for nitrogen removal. The discussion focuses on the need for careful monitoring and pretreatment to minimize negative effects on the denitrification process and promote the use of these sustainable options for wastewater treatment and environmental protection.

During the 20th century, the construction of dams and large reservoirs was a common approach by water managers to control hydrological variability and alleviate the effects of hydrological extremes (i.e. floods and droughts). However, the complex human-water relationships arising in response to reservoir construction can lead to unexpected (and often undesired) outcomes, which diverge from the original intentions. Sociohydrological models explicitly account for feedbacks between society, the environment, and water resources. As such, they provide opportunities to: i) uncover the dynamics of hydrological risks generated by the interplay of human and water systems, and ii) explore trade-offs in the management of water resources, thereby informing the decision-making process. This study develops a sociohydrological model for two diverse case studies in Australia, to explore the human-water interplays emerging from the occurrence of drought and flood events in an urban and rural context. The model is used to explore alternate water management scenarios with respect to trade-offs between: i) the environment vs. irrigation (Case Study 1); and ii) urban water supply vs. flood mitigation (Case Study 2). The model outcomes are compared to observed hydrological conditions, socioeconomic characteristics, and water management decisions. The findings show consistency between observations and simulations, and align with analysis from other studies, validating the model. Model results indicate the emergence of several sociohydrological phenomena in each case study. The comparison of the case study results shows: i) differences in the way rural and urban consumers respond to drought; and ii) that the role of reservoir operators is more significant in the urban setting. This study finds that the model can be a useful tool for water managers increase catchment understand, to explore the potential outcomes of alternative water management decisions, and to identify preferred trajectories across multiple hydrological and socioeconomic criteria. Keywords: sociohydrology, system dynamics

In order to calculate the groundwater level it takes a well-adjusted model and understanding of the processes affecting the groundwater level. The general assumption that all-ready-formed groundwater won’t be affected by water uptake by vegetation was questioned when diurnal fluctuations in groundwater levels were observed during dry summer months in a few locations.  The aim of this work was to prove that the origin to the diurnal fluctuations in groundwater level was water uptake by vegetation, and that this also influences the speed by which the groundwater level declined. The diurnal fluctuations in the groundwater level were observed in a small selection of measuring stations for measuring groundwater levels, all placed in till. Using spectral analysis, it was established that the diurnal fluctuations had the same periodicity as the water uptake by vegetation. The groundwater level declined during the day when vegetation consumes water, and increased again during the night when the consumption of water by vegetations reduces.

In “Mälarbananprojektet”, Trafikverket (The Swedish Transport Administration in Stockholm) want to expand the railway. Mälarbanan is at the present a railway that extends between Stockholm and Hovsta. The railroad will be expanded to four tracks from two tracks and the aim of the Mälarbanan project is to separate commuter trains from other trains. As there is limited space on the surface, space underneath the surface must be used. This is why it is important to determine how far below the surface the construction will have to take place, which most likely will require a groundwater drawdown. This thesis focuses on an area with two reference points in Solna. A lowering of the pressure levels normally affects the surrounding in the form of subsidences, also known assettlements​, in the ground. As the area has a clay layer believed to be around 7 m thick, and clay is sensitive to groundwater drawdowns, the drawdown must be minimal. The soil engineers have established that the maximal groundwater drawdowns should not exceed 3.0 m, as anything over 3.0 m may cause extreme settlements in the settlement sensitive clays over the next 100 years. The modelling of drawdown and pore pressure conditions is conducted in a software called ​Visual MODFLOW.​ These different groundwater drawdowns, or scenarios, computed in the settlement calculations are 0 m, 0.3 m, 1 m and 3 m. The calculations have been computed for 1, 2, 5, 20, 40 and 100 years from now. Besides settlement occurring from groundwater drawdown, settlements in the form of primary and secondary consolidation (creep) normally occur from constant loading. This requires a software for settlement calculations that takes creep effects into consideration and the software used in this case was ​GS Settlement​. The parameters necessary for the calculations are obtained by conducting CPT, collecting undisturbed soil samples for fall cone tests and CRS-tests in a laboratory. These methods are supposed to decide how and if the project can proceed. / Trafikverket i Stockholm planerar att bygga ut Mälarbanan i samarbete med WSP. I nuläget sträcker sig Mälarbanan från Stockholm till Hovsta. Planen är att bygga ut från två spår till fyra spår och därmed separera pendeltåg från andra tåg. Då det finns begränsat med utrymme på ytan, måste man utnyttja utrymme under ytan. Detta kräver mest troligt en grundvattensänkning. Detta arbete fokuserar på två punkter i Solna Business Park. Grundvattensänkning påverkar omgivningen genom att bilda sättningar, en sjunkande rörelse i markytan. Då lera är extremt känsligt mot grundvattensänkningar, och lermäktigheten under markytan är ca 7 m, bör man sänka grundvattenytan så lite som det går. I detta projekt vill man inte sänka grundvattenytan med mer än 3,0 meter, då sänkningar som överstiger 3,0 m kan leda till extrema sättningar i den sättningskänsliga leran de kommande 100 åren. Detta, i samband med portryckssituationen, modelleras i ​Visual MODFLOW​. Programmet producerar en situation för varje sänkning. Dessa sänkningar är: 0 m, 0,3 m, 1 m och 3 m. Detta implementeras i sättningsberäkningar i ​GS Settlement​, som beräknar sättningarna de kommande 100 åren. Detta program tar med krypsättningar i beräkningarna. Parametrar som krävs för detta kommer från CPT, fallkonstester och CRS-tester i laboratorium. Dessa beräkningar ska avgöra huruvida projektet ska fortgå, om det nu kan fortgå.

During the past three years, substantial parts of Sweden have experienced a decrease in the groundwater levels, whereas some geographical areas were more affected than others. Requests from the government, counties and municipalities have been sent out to the citizens, to attract attention, increase awareness and decrease the use of drinking water. The communication strategies have looked different in the municipalities depending on their water situation, prerequisites and resources. This study aims at explaining how five municipalities in Jönköping county communicate with their citizens regarding water resources and use of drinking water. The five participating municipalities are; Jönköping, Mullsjö, Habo, Värnamo and Eksjö. Jönköping county is one of the counties that were affected by the low groundwater levels, if so to varying degrees, which is the reason the study focuses on Jönköping county. Therefore, the purpose of this thesis is to examine how municipalities communicate in relation to intervention strategies, to create a behavioural change regarding the use of drinking water among citizens. Intervention strategies were analysed in the study to compare the municipalities’ communication work and have been used as an analytical tool during the process. Intervention strategies can be separated into antecedent strategies and consequence strategies to change behaviour. The antecedent strategies consist of commitment, information, goal setting and modelling, and consequence strategies consist of feedback, rewards and prompts. A combination of multiple strategies has been proven to create a more extensive impact, and behavioural change can, in that way, easier be accomplished. A total number of seven interviews were performed for collection of data. Two communication managers from Värnamo and Eksjö municipality participated, and five Water and Sewer Manager from Jönköping, Mullsjö, Habo, Värnamo and Eksjö municipality. An important factor that has been taken in consideration is that the municipalities take their water from different sources and in that way are affected in various extensions of the low groundwater levels. In that way, the municipalities have communicated the question of water differently. The result of the study shows that ongoing communication work regarding the use of drinking water is done, mostly by spreading information. Two municipalities use multiple strategies in their spreading of communication. The result also shows that there is no underlying communication work regarding a decrease in the use of drinking water. Instead, it has been demonstrated that the communicative work takes place when a crisis occurs.