Mosquitoes are found in extremely large numbers in the lower parts of the River Dalälven. In the year 2000 the mosquito nuisance was especially high, resulting in foundation of the Biological mosquito control project. Since 2001 mosquito larvae are controlled by using a biological pesticide BTI (Bacillus thuringiensis ssp israelensis). The mosquito fauna in the area is dominated by Flood water mosquitoes, a group of mosquitoes that are very aggressive and form new generations of mosquitoes during every single flooding event during the summer. To be able to efficiently control the mosquitoes it is essential to know the extension and locality of the flooding.

The discharge from Lake Mälaren is regulated to keep the lake water level within limits set by a water decree. Despite this, in the year 2000 the lake water level rose above the upper limit. Studies conducted at the climate modeling unit Rossby Centre at the Swedish Meteorological and Hydrological Institute (SMHI) indicate that the inflow to the lake may increase in the future. A flood in the area will, among other things, strike infrastructure and residential districts.The aim of this study was to investigate the water levels of Lake Mälaren in future climates. In addition to this possible future expansion of the lake discharge though the sluice gates in order to keep water levels below limits set by the water decree and to prevent flooding of the shoreline were discussed.

Francisella tularensis, the causative agent of the zoonotic disease tularaemia, is highly contagious and potentially fatal for a wide range of wildlife species of the northern hemisphere, also humans. Although recognized as a pathogen for over 100 years, much still remains to be elucidated concerning the ecology and transmission of the bacterium, hence this literature overview aims at compiling data regarding the aquatic association and the role of mosquitoes in transmission of Francisella tularensis subspecies holartica, the sole subspecies in Sweden. While a linkage between the bacterium and natural waters stands beyond dispute, there is no consensus in the literature concerning its potential as a reservoir. However, two prevailing theories can be distinguished; one proposes the water association being mammaldependent and thus merely the result of contamination from semi-aquatic mammals living in close vicinity to the water source. The other, quite contrary, suggests mammal-independence and hence that water, possibly in association with protozoa, serves as an environmental reservoir for the bacterium.

Agricultural drainage is widely used to manage the amount of water in the ground in order to improve conditions for cultivation. However the effects of drainage companies on water regimes are considerable leading to runoff changes such as altered stream flows, peak flows and water levels. In a greater extent this could imply an increased risk for floods along affected watercourses. This study analyzes the extension of agricultural drainage within the drainage basin of Trosaån in Sweden by ArcGIS mapping. In a statistical analysis, historical variation in streamflow in relation to mean precipitation and mean temperature are investigated for the study area.

Storm water management has become a more important matter as urban areas are expanding and natural areas are being exploited. As nature landscapes are being converted into hard surface areas storm water flow is affected both in terms of velocity and size. A flow increase can easily result in a flooding if the dimensions of the pipeline system are inadequate. Considering predicted upcoming climate changes, flooding?s may become more common in urban areas in the future.

Severe floods caused by heavy autumn rains in year 2000 raised the question whether measures to reduce the damage from high water levels, in the area surrounding lake Glafsfjorden and along the river Byälven down to lake Vänern, are possible. One option is to reduce flow resistance along the river and thereby lower the maximum water level a given inflow would cause. Good knowledge of hydraulic and hydrological conditions is necessary in order to estimate the effect of such flow-reducing measures. In order to quantify such effect a 1-dimensional hydraulic flow model has been set up for the river Byälven using the software package MIKE 11. The model is more detailed, especially concerning topography and bathymetry, than earlier models used for studies of the river.

Flooding events are no longer rare, floods occur all over the world. Accordingly, it is vital for the society and different authorities to work with flood mapping. To meet the goal of Uppsala kommun to map the risks of floods in Uppsala län, a map of the different areas around Funboån which are inside the area of risk for flooding have been developed.In the work, cross sections and the water flow have been measured. Moreover, an echo-sounding have been carried out in Funboån to map the bottom topography. From the bottom map and laser scanned data covering the study area, a terrain model was created.

Japanese encephalitis virus (JEV) is a significant vector-borne zoonotic pathogen, causing devastating encephalitis in humans. Its geographical range includes a majority of Asian countries and has also been recognized in some western Pacific areas. The main vectors of JEV are mosquitoes belonging to the genus Culex. Birds and pigs function as hosts and virus amplifiers, whereas humans are accidental hosts. Japanese encephalitis is commonly regarded as a rural disease.

Risk-based sampling program of microorganisms in the water source in northern SwedenAfter several disease outbreaks caused by parasites in the drinking water during the last years, it is more essential than ever to insure that the water supply companies have enough barriers to counteract the presence of microorganisms in the outgoing water. It is also discussed whether climate changes such as increased precipitation can have a connection to the increased cases of parasites in water sources. The water source at Gäddvik is Luleå municipality?s largest and provides drinking water to 64 500 of Luleå?s 74 000 inhabitants. The investigation of microorganisms in the water source, especially in the Lule River has not been as prioritized as the sampling of chemical parameters.

In Dar es Salaam, as in many cities in developing countries, green areas are decreasing due to the fact that the growth of buildings, infrastructure and services has become a priority. As the population increases more buildings and infrastructure are needed and much of the building activity takes the form of uncontrolled settlements, which encroaches the public green space. Dar es Salaam has approximately three million inhabitants, of which about 70 percent are living in informal settlements. The aim with this study is to make a design proposal for a park and recreation area where the Msimbazi river basin in the centre of Dar es Salaam is today. The basin consist of a few playing fields, footpaths and some urban farming, but apart from this it mostly consists of unused grasslands, swamps and forests. Because it is an unsafe place and badly connected to the rest of the city infrastructure, it has become a barrier. The annual flood combined with the constant still shallow water creates a good breading ground for malaria mosquitoes.

In today?s World is climate change an important and hot topic. Climate scenarios for Sweden show a warmer climate, especially during the autumn, winter and spring. The same climate scenarios also show that the precipitation will increase during this part of the year, however, during the summer the opposite is expected to occur. The purpose of this essay is to examine how future climate change will affect Stockholm especially the expected increase in precipitation, which may lead to a rising level of the Lake Mälaren. During 2000/2001 was Stockholm hit by a flood. This flood nearly resulted in major consequences and showed that there were significant risks for the city of Stockholm and increasing precipitation will result in even more water in the drainage systems of Lake Mälaren. The results presented here show that it is important to increase the drainage capacity of Lake Mälaren in order to reduce the risks of flooding in the central parts of Stockholm.

The location on the river delta of Klarälven, adjacent to lake Vänern, makes Karlstad one of the Swedish cities where a significant flood risk is present. The city has several major floods in its memory which has caused great material damage and economic losses, the latest of which occurred in the winter of year 2000/2001. The purpose of the study is to examine how the approach to flood risk has changed in the municipality of Karlstad since the 1950s, and how this change has affected the current situation regarding the city's vulnerability to flooding. To investigate this, a document analysis was conducted, where key documents in the media and from the municipality of Karlstad was studied. Furthermore, an interview study was conducted with respondents who currently are employed or previously have been employed in the municipality of Karlstad, who in various ways work with issues of flood risk. The result of the study shows that several changes have taken place since the 1950s in terms of the municipality's approach to flood risk, which for instance has led to preventative measures being taken to a greater extent than previously in the physical planning.

The effects of the climate changes are expected to generate several substantial direct and indirect consequences on both ecosystems and societies. It is the extent of the negative consequences that determents the vulnerability of the things or the ones exposed. The knowledge of the effects and consequences by a changing climate provides an opportunity to take measures to reduce the vulnerability.Our society?s vulnerability depends on how we choose to act out of the existing knowledge and what measures we choose to take. Karlstad municipality has good knowledge and perception of the increased flood risks the climate changes will generate and the probable consequences that most likely will follow. How the municipality decides to manage the flooding issue is not just affected by the will to mitigate the vulnerability but also by the vision to increase the number of citizens.

This report is about the experiments with mixing of the separated water and the vacuum pump seal water at Hellisheiði power plant. This is done to prevent silica scaling and clogging in pipes and reinjection wells as well as eliminating vacuum pump seal water from the plant. The experiments were done in four stages: the first stage comprised of tests with different flows of separated water at 70°C, the second stage was carried out by mixing the separated water at 70°C and the seal water with different amounts of the seal water, the third and the fourth stages were like the first and second but with the separated water at 120°C. The results show that this method is good if the mixture is around 50/50 separated water and seal water, to control the silica scaling in the separated water and to be able to reinject the seal water with the separated water. This does not eliminate the silica scaling in all of the separated water because the amount of separated water is much more than the amount of seal water that comes from the plant. .

We all know that water is very important for both animals and humans. When we are weaning the piglets from the sow we must guarantee that the piglets can start to drink more water instead of sow milk. The first thing to check is always the quality of the water that is to be used. To secure that, you must take a water sample. If the water is inadequate it can bring a lot of problems and diseases.