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 “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.

Groundwater is a crucial part of the hydrological cycle and is an important source for drinking water, irrigation and industry, particularly during droughts. With climate change, the hydrological variability is predicted to increase, making predictions for recharge and groundwater storage even more important to implement and to maintain sustainable water use. This study examines the importance of model spin-up in simulating recharge using the Hydrus-1D computer model. The focus is on two previously made Hydrus-1D models that represent end members in climate and hydrology; one which is a natural grassland in a semi-arid climate, while the other is a low impact development (LID) bioswale site in a Mediterranean climate. The main goal of this study is to characterize the range and causes of spin-up behavior as well as to analyze the extent of the effects that the spin-up process has on the recharge simulations. Although there has been some research on spin-up behavior for surface-water models, there is still a knowledge gap regarding the effects of model spin-up on vadose zone models simulating recharge. The initial conditions varied using three parameters for each of the two models: time (3, 15 and 30 years), initial moisture (θ = 0.1, 0.2 and 0.3) and precipitation (25% drier than historical data, historical 30-year data, 25% wetter than historical data). The output from these spin-ups were then used as initial conditions in simulating recharge using the 15-year models. The study found that the impact of spin-up is significant in the natural grassland site where there is a slow response between atmospheric forcings and recharge and where there is a relatively thick vadose zone. Especially spin-up time showed great variability and there is an inverse relationship between spin-up time and magnitude of recharge, where the longer spin-ups had lower recharge rates. Initial water content and precipitation did not result in different recharge amounts for the LID model. Length of spin-up only had very small differences in recharge for the LID models, indicating they are less sensitive to changes in initial spin-up parameters.

Boreal landscapes cover a large part of both Sweden and the northern hemisphere. The hydrology of the boreal landscape is complex, with several factors that can affect it in a physical and/or chemical manner. In the Krycklan catchment area, 68km2, located in northern Sweden close to Umeå, data has been collected at several sites giving both stream flow and water chemistry information. In 2017 samples from 34 sites were collected and analysed from ephemeral streams within the Krycklan catchment area for the first time ever.  In this project, data that has been collected from the ephemeral streams will be correlated with data from the perennial streams in the catchment area. There are several hypotheses at the start of this project that suggests that within the ephemeral streams the DOC will be lower, and the CO2 will be the same. The aim of the project is to find out if there are any patterns that differentiates the ephemeral streams from the perennial streams or if there are no patterns at all. Since there is not so much data available for the ephemeral streams, the conclusions that might be reached in this project won’t be completely reliable. However, if interesting patterns are found the project could expand in the future and more samples can be taken to use for more precise analyses. / Boreala landskap täcker en stor del av både Sverige och norra halvklotet. Det boreala landskapets hydrologi är komplext, med flera faktorer som kan påverka det på ett fysiskt och/eller kemiskt vis. I Krycklans avrinningsområde, 68 km2, beläget i norra Sverige nära Umeå, har data samlats in på flera platser som erbjuder data för både flöde och vattenkemi. År 2017 samlades prover från 34 efemära strömmar och analyserades för första gången inom Krycklans avrinningsområde. I det här projektet kommer data som samlats från de efemära strömmarna att korreleras med data från de konstanta vattendragen i avrinningsområdet. Det finns ett par hypoteser i början av detta projekt som tyder på att inom de efemära strömmarna kan DOC halter vara lägre och CO2 halter kommer att vara densamma. Syftet med projektet är att ta reda på om det finns några anmärkningsvärda skillnader mellan de efemära strömmarna och de konstanta vattendragen. Eftersom det inte finns så mycket data tillgänglig för de efemära strömmarna kommer de slutsatser som kan uppnås i detta projekt inte att vara helt tillförlitliga. Om intressanta mönster finns däremot kan projektet expandera i framtiden och fler prover kan tas för att användas för mer exakta analyser.

The percolation of water through waste rock dumps at mine sites can lead to the production of a leachate with high concentrations of dissolved metals, sulfate and nitrogen compounds. It is important to understand how water flows in waste rock dumps in order to predict the environmental impact of this leachate on recipients. The dynamics of percolation and leachate discharge are controlled by climatological conditions at the site, where relatively large flows in northern Sweden correspond to snowmelt during late Spring. Rock dumps are often tens of meters in height, resulting in an unsaturated water flow system through heterogeneous material. Hence, the simulation of leachate generation requires an accurate representation of the subsurface materials as well as the flow processes, where water flow in waste rock dumps is dominated by matrix flow with macropore flow being of secondary importance. Matrix flow is rather slow and may thus potentially yield relatively high concentrations of contaminants in the leachate, in response to precipitation and snow melt. This study uses Hydrus-1D to predict leachate generation from a small-scale waste rock dump in Kiruna in terms of discharge magnitude and timing. The 3-dimensional geometry of the waste rock dump is approximated by summing simulations from 1225 one-dimensional columns of different length, with a surface area of 1 m2 each. There are four output parameters that are compared between the model results and measured data: snow accumulation, water content, temperature, and discharge. There are some discrepancies between the model results and field measurements, most likely due to uncertainties in the input parameters (especially waste rock properties), limitations in the Hydrus-1D model (i.e. freeze-thaw dynamics), and assumptions that are used in constructing the conceptual model. For better agreement between model results and measured data, a new modelling approach is recommended, potentially using a different program than Hydrus-1D.