Avrinningens förändring i tid och rum beror av såväl klimat och årstid som av avrinningsområdets fysikaliska egenskaper. Kunskap om förändringar i avrinningsdynamiken är av stor vikt vid konstruktion av hydrologiska modeller. Avrinningsområdena i denna studie ligger inom NOPEX-projektets försöksregion. Regionen är ungefär 50 x 100 km2 och ligger till största delen nordväst om Uppsala. Områdena varierade i storlek från 0,45 till 11,5 km2. Tre av områdena var rena skogsavrinningsområden. De övriga två områdena var avsevärt större och utgjordes till största delen av skogs- respektive jordbruksmark. Den studerade perioden sträcker sig från juli 1994 till juli 1995. Avrinningsdynamiken studerades genom jämförelser av hydrogram, vattenbalanser, fördröjning snösmältning – avrinning, förändringen av avrinningens andel av det till området tillförda vattnet och analys av recessionskurvor. Dynamiska vattenmagasin har uppskattats genom integration av recessionsekvationer och magasinskoefficienter har uppskattats. Skillnaderna i avrinningsdynamik mellan områdena var i vissa fall avsevärda trots likartade fysikaliska egenskaper. Det minsta skogdominerade avrinningsområdet uppvisade en mycket avvikande avrinningsdynamik med stora avrinningstoppar under tidig höst, en vattenbalans med mycket hög avrinning, liten fördröjning snösmältning – avrinning och snabb recession. De övriga tre skogsdominerade områdena hade inte lika accentuerade skillnader i avrinningsdynamiken. Det av jordbruksmark dominerade området intog även det en särställning med litet och långsamt gensvar på nederbörd och en recessionskurva vars form inte liknade något annat område. Analysresultaten i detta arbete gav fingervisningar om vilka processer och förlopp som är av stor vikt vid beskrivning av avrinningsdynamiken i hydrologiska avrinningsmodeller. Den ibland mycket stora rumsliga variationen i avrinningsdynamik tydliggör de representativitetsproblem som är förknippade med användandet av regionala modellparametrar. / Changes of runoff in time and space are dependent on climate and season as well as on the physical properties of the catchment. Knowledge of changes in runoff dynamics in time and space is of great importance in the construction of hydrological models. The five catchments in this study were located in the NOPEX region. The region is approximately 50 x 100 km2 and it is located northwest of Uppsala. The studied catchments varied in size from 0.45 to 11.5 km2. Three small catchments were forested. The other catchments were larger and were dominated by woodlands and farmlands. The studied period extended from July 1994 to July 1995. The runoff dynamics were studied through comparisons of hydrographs, water balances, delays between snowmelt and runoff, variations in the runoff fraction of the water input to the area and analysis of recession curves. The dynamic groundwater storage was estimated by integrating the recession equations. The storage coefficient was also estimated. The differences in runoff dynamics between the catchments were considerable in some cases despite physical similarities. The smallest wooded catchment showed very different runoff dynamics with large runoff peakflows during early fall, a very large runoff in the waterbalance, a short delay between snowmelt and runoff and a quick recession rate. The differences in runoff dynamics between the remaining three wooded catchments were not as accentuated. The catchment dominated by farmland held a unique position with a slow runoff response to precipitation and a recession curve with a different shape. The results of this study gave pointers to the processes that are of great importance in describing the runoff dynamics in hydrologic runoff models. The sometimes large variation in runoff dynamics in space elucidates the problems with representativity associated with the use of regional model parameters.

I denna uppsats har den laterala och den longitudinella dispersionen studerats i en grusås, (Finnerödjaåsen) med hjälp av spårämnesmärkning. Spårämnet, NaI injicerades i ett grundvattenrör. Jodidkoncentrationen i grundvattnet mättes i injiceringsröret, i sju grundvattenrör placerade tvärs över åsen och i ett rör 50 meter nedströms injiceringsröret. För att bestämma den laterala och den longitudinella dispersionskoefficienten användes en förenklad modell som förutsätter laminärt flöde i ett homogent medium. Modellen visade god överensstämmelse med försöksresultaten från Finnerödjaåsen. Den laterala dispersionen beräknades till 2.4 m2/dygn. Den longitudinella dispersionen visade sig vara mycket större i åsens kärna, ända upp till 260 m2/dygn än någon meter från kärnan ut mot åskanten där dispersionen i genomsnitt var 16 m2/dygn. Hastigheten hos grundvattnet i åsens kärna var ungefär dubbelt så stor som i övriga åsen och troligtvis transporteras största delen av flödet i en liten del av åsens mitt. / The lateral and longitudinal dispersion of groundwater was studied in a gravel ridge, (Finnerödjaåsen) in the central part of southern Sweden. NaI was injected into a groundwater tube. The iodine concentration in the groundwater was then measured in the injection tube, in seven groundwater tubes placed in a transverse row 1,5-4 m apart 20 m downstream the injection tube and in one tube 50 m downstream the injection tube. The coefficients of lateral and longitudinal dispersion were determined by using a model assuming laminate flow in a homogeneous medium. For the gravel ridge examined, there was a good fit between the experimental data and this model. The lateral dispersion was found to be 2,4 m2/day. The longitudinal dispersion was much larger in the narrow passage in the middle of the ridge, 260 m2/day, than in the marginal zones of the ridge, 16 m2/day. The flow velocity of the groundwater in the middle of the ridge was about twice as large as the flow velocity in the rest of the ridge, i.e. the bulk flow of groundwater occured in the middle of the ridge.

Övergödning är ett av Sveriges mest allvarliga miljöproblem. Genom utsläpp till följd av antropogen verksamhet läcker näringsämnen ut i vattnet. Den senaste undersökningen av Stockholms stads grundvatten har kartlagt halterna av kväve och fosfor. Eftersom grundvatten är en del utav det hydrologiska kretsloppet, och efter en viss omsättningstid övergår till ytvatten, påverkar kvalitén hos grundvattnet recipienten samt det ekosystem som denna ingår i. Rapporten ämnar undersöka halterna av kväve och fosfor i grundvattnet utifrån befintliga bedömningsgrunder samt kartlägga huruvida grundvattnet bidrar till övergödning av Stockholms kommuns ytvattenförekomster. Detta är av vikt för kommunens vattenförvaltning i linje med EU:s vattendirektiv och mål om god status för vattenförekomster, men även för att verka mot landets miljökvalitetsmål. Miljöförvaltningens undersökning av grundvattenkvaliteten visar på höga halter av fosfor samt ammoniumkväve. Halterna av nitrat samt nitrit är enbart höga i vissa av provpunkterna. Halterna av främst fosfor och ammoniumkväve kan enligt bedömningsgrunder ha övergödande effekt på ytvattendrag. En översiktlig undersökning baserad på grundvattnets strömningsriktning visar att kommunens vattenförekomster får ett tillskott av vatten via grundvattnet inom kommunen. Detta finns representerat i kvalitetsundersökningen av grundvattnet varpå slutsatsen dras att ytvattenförekomsterna inom kommunen påverkas negativt av grundvattnet. / Eutrophication is one of Sweden’s most severe environmental issues. Due to emissions through anthropogenic activity nutrients are added to aquatic systems. The latest analysis of the Stockholm municipality groundwater has examined the levels of nitrogen and phosphorus. Due to the fact that the groundwater is part of the hydrological cycle and will eventually reach the surface water, the condition of the groundwater will affect the recipient and correlating ecosystem. This report aims to analyze the levels of nitrogen and phosphorus in the groundwater of Stockholm based on current national quality standards, and to identify whether the groundwater is contributing to the eutrophication of the surface water bodies in the municipality of Stockholm. This is of significance regarding the water management in Stockholm municipality, based on the EU water framework directive, and the target of achieving good status for all water bodies. It is also of great importance regarding the Swedish environmental quality objectives. The groundwater quality analysis indicates high levels of phosphorus and ammonium. The nitrate and nitrite levels are only excessive in certain cases. Primarily, the levels of phosphorus and ammonium may, according to national quality standards, have eutrophic effect on surface water bodies. A cursory examination based on the flow directions of the groundwater, indicates that the municipality’s surface waters are supplied with water from the municipality’s groundwater. This correlation is represented in the analysis of groundwater quality and it is therefore concluded that the groundwater has a negative impact on the surface water bodies within the municipality.

Time-lapse reflection seismic methods have proven effective fordetecting and monitoring the injection and spreading of geologicallystored CO2. These methods are based on interpreting changes in themedia’s elastic properties that result from replacing the native salinewater by the injected CO2, which in turn affects the seismic velocitiesof the media. Since applications of these methods in the field areexpensive, and the interpretation process is time consuming, pre-studyinvestigations should be done in order to determine whether or notreflection seismic surveys can successfully be applied to monitor theCO2 plume in the case of interest.In the present study, CO2 injection and migration in a deep salineaquifer based on a structure situated below the south-western part ofthe Baltic Sea was modeled. To determine the CO2 saturationdistributions at different times, the injection was numericallysimulated using TOUGH2/ECO2N. A radial-symmetric model withhomogeneous and isotropic properties was assumed and two differentinjection rates were studied, with the results analyzed at differenttimes after the start of the injection.The saturation and density values resulting from the TOUGH2simulation were converted to seismic velocities using the Biot-Gassmann model. A synthetic velocity model was built based on bothTOUGH2 and Biot-Gassmann models and synthetic seismic responsefields before and after injection were generated. The results show thatthe amplitude changes in the seismic response are detectable even forsmall amounts of injected CO2, while noticeable signs of velocitypushdown, as a signature of the CO2 substitution, could only beobserved if the injection rate is high enough.

The understanding of where the streams begin is an important factor in both hydrology and geomorphology, as well as for land use activities. Despite this, only a few research projects have been done in a snowmelt-dominated boreal landscape. The main objective in this study is to see if one could predict where a stream initiates by knowing possible controlling factors. Data points from stream initiation points in the boreal landscape of Krycklan, situated 50 km Northwest of Umeå, were analyzed. Krycklan is a well-known research area and a lot of research projects have been done here. The landscape is diverse and most of the streams have been modified by human impact. The data points were collected with help of a Global Positioning System (GPS) during three different sampling campaigns; May 2012, May 2013 and August 2013. Maps were made from a Digital Elevation Model (DEM) showing slope, elevation and contributing areas for the stream heads. No clear relationship between the contributing area and slope could be found in this area, although it has been demonstrated in more semi-arid climates. The results show that other factors than the contributing area, elevation and slope seem to have a greater impact for the initiation of streams in a boreal landscape. The results were expected because of the modifications done for the streams.

An isotope analysis using stable water isotope ratios, δ18O and δ2H, paired together with PFAS monitoring has been conducted to achieve a comprehensive understanding of the groundwater origin, transport processes and PFAS contamination dynamics for a portion of the Uppsala Esker affected by artificial infiltration. This information is valuable in developing strategies to meet the water demand that is expected to increase with the growing population, manage and reduce the PFAS contamination and protect the drinking water supply in Uppsala. The foundation of this project is a large set of δ18O and δ2H isotope data stretching back to 2014 until today, provided by Uppsala Vatten, as well as water samples taken between September and November 2023 at six groundwater sampling points in the area around Tunåsen, Uppsala. These six sampling points consisted of four groundwater observation wells, Galgbacken’s wellfield and Tunåsen’s infiltration chamber where water from Fyrisån passes through before being infiltrated in the aquifer.     By determining the travel time of the water through the esker from the infiltration point to the wellfield using the stable isotopes δ18O and δ2H the travel time was found to be on average 225 days and the average speed of water at this site was found to be 1·10-4 m s-1. By calculating the percentage of infiltrated surface water from the Tunåsen infiltration chamber in Galgbacken wellfield, a blending ratio could be assessed. This blending ratio was found to be on average 89 % surface water from river Fyris and 11 % virgin groundwater originating from north of the study area. When investigating the PFAS concentration at the six sampling points between Tunåsen and Galgbacken sampling point D showed high concentrations of PFAS indicating that there might be a point source near that sampling point. The PFAS composition did not change drastically along the travel path and not all PFAS comes from infiltration.  The isotope analysis can be used as a tool to estimate when a high total PFAS concentration found at Tunåsen is likely to reach Galgbacken, however it cannot be used to draw conclusions about the transport of individual PFAS substances or composition profiles.

No description available.

To facilitate robust understanding of the processes and properties that govern a groundwater system, managers need data. However, this often requires them to make difficult decisions about what types of data to collect and where and when to collect it in the most cost - effective manner. This is where data worth analysis, which is based on predictive uncertainty analyses, can play an important role. The ‘worth’ of data is defined here as the reduction in uncertainty of a specific prediction of interest that is achieved as a result of a given data collection strategy. With the use of data worth analysis, the optimal data types, sample locations, and sampling frequencies can be determined for a specific prediction that informs, for example, management decisions. In this study a data worth method was used to optimize data collection when predicting pumping - induced stream depletion (water quantity section) and when predicting changing nitrate concentrations as a result of land-use change (water quality section). Specifically, the First Order Second Moment (FOSM) based data worth method was employed. This thesis also builds upon previous work which explores the impacts of spatial model parameterisation on the performance of the data worth analysis in the context of stream depletion assessments. A transient groundwater model was developed, using the MODFLOW-NWT software, and a steady state transport model was developed, using the MT3D-USGS software for the mid-Mataura catchment located in Southland, New Zealand. The ‘worth’ of both existing and additional potential monitoring data were investigated. In addition, and for only the water quantity part of the thesis, three spatial hydraulic parameter density scenarios were investigated to assess of parameter simplification on the performance of the data worth method: 1) distributed pilot-point parameters, 2) homogeneous parameters, and 3) grid-cell based parameters. The water quantity (stream depletion) predictions were made at 2 key locations: (i) the catchment outlet at Gore and (ii) the outlet of a spring-fedstream (McKellar Stream). The water quality prediction (change in nitrate concentration due to land-use change) was made at 7 locations 4 key surface water locations, 2 town supply bores at Gore and one additional groundwater location further upstream. For the water quantity predictions, results show that the existing transient groundwater level data resulted in the largest reduction in uncertainty for the predictions examined. Because the low flow predictions at Gore were integrating predictions, the most uncertainty reducing observations were scattered through the catchment area with a focus on the north-west. This coincides with the recharge zone (which means that there are large water level fluctuations and hence a larger ‘signal to noise’ content in the groundwater level data). In contrast, because McKellar Stream is a discrete prediction (in this case, because McKellar Stream is spring-fed), the observations directly surrounding the stream reduce the uncertainty the most significantly. The impact of parameter simplification in the water quantity modelling showed that the data worth analysis using the grid-cell based parameterisation were very similar to those using pilot-points. However, when using the homogeneous parameterisation, the data worth results became corrupted by the lack of spatial variability available in the parameterisation. Indicating that spatial heterogeneity is needed when predicting low flows, as was shown by previous studies. However, the computational time associated with performing data worth uncertainty analyses is much higher with a grid-cell based parameterisation. A pilot-point based scheme should perhaps therefore be considered a favourable option. For the water quality predictions, results showed a strong correlation between the hydraulic conductivity, porosity and denitrification. This is likely because the hydraulic conductivity and porosity provide information about the velocity of the groundwater for a given hydraulic - head gradient, which provides information about the amount of time available for denitrification to take place in the soil substrate. Next to that, results showed no distinct difference between surface water and groundwater predictions when predicting changing nitrate concentrations, but they showed that the spatial data worth patterns depended on the proximity of the prediction location to the denitrifying areas. Overall it can be concluded that spatial parameterisation is needed when performing a data worth study for stream depletion predictions, however a more detailed parameterisation than pilot – points does not provide significantly more information. Next to that, it can be concluded that the spatial data worth patterns when predicting low flows mainly depend on if the predictions are integrating or discrete predictions. Lastly, it can also be concluded that the data worth patterns when predicting change in nitrate concentration depend on the proximity of the prediction location to the denitrifying areas.

Pakistan is a densely populated country; and its population is increasing rapidly. More than fifty percent of population is living in rural areas and is related to agricultural sector. Punjab is the most populated province of Pakistan. Irrigation system of Punjab is not very developed. The present irrigation system is almost hundred year old. The management of existing irrigation system is a big challenge. With increase in population, load on existing irrigation system is also rising and situation is presenting serious problems. This report addresses main problems related to management of irrigation system in district Sargodha of Punjab province of Pakistan. The problem with management of existing irrigation system includes social as well as technical problems. This report also discusses loss in agricultural production due to mismanagement of irrigation system. Further, report also suggests possible solutions for the management of irrigation system. These solutions take into account reforms in social sector as well as introduction of new technology. For the assessment of report, past research related to management of irrigation system in Indus basin has been studied. This research also includes ideas of previous researchers about management of irrigation system and then we try to conclude possible solutions for better management of irrigation system in area.

The future of global water supply and availability is one of the most important questions facing life on earth today, and experts agree that the most pressing angle to approach the question from is its governance. However, water represents one of the worlds broadest and most complex fields of governance due to its cross thematic and cross-boundary reach, as well as an increase in new actors through privatisation and transnational corporate influence.  In order to actively implement new governance approaches the current system, its actors, connections and influence strategies must be identified. This study combines three theoretical and methodological approaches to study our current global water governance structure: Neo-Gramscian, Network analysis and Policy Entrepreneurship. The Neo-Gramscian influence theory is used to identify 3 types of connections between actors. The resulting data is then used for network analysis to identify the key actors within the field. Once these key actors have been identified, all Nestlé (as a case study for transnational corporations) connections to said actors and the field of water governance have been highlighted under the combined theoretical lenses of Neo-Gramscian influence and Policy Entrepreneurial strategies. These three theories are used in conjunction for several reasons: All three theories represent a different perspective of analysing the decentralised, large scale governance of a complex system. While network analysis allows for the visual representation of the governance “space” and for the identification of key actors and their connections, the Neo-Gramscian and policy entrepreneur approaches give insight into how these connections might be used and created in order to lead to a position of influence within the system. The results show a list of 42 key actors to whom Nestlé has a large number of self-reported connections across all 3 influence types. It further shows that Nestle actively uses at least 3 of the 4 entrepreneurial strategies on some of these connections. This suggests that Nestlé may have some significant influence in global water governance. The study is also a proof of concept for the synthesis of the three complementary theories.