Eutrophication of lakes and streams are nowadays a well known environmental problem and implies an enrichment of the nutrients phosphorus (P) and nitrogen (N). Phosphorus is considered to be the most important component for the growth of aquatic plants and leads in too large quantities to an intensification of growth. Phosphate (PO4) is the fraction of phosphorus that can easiest be taken up by plants and thus have the greatest impact on eutrophication. Increased plant growth in lakes and unfavorable conditions for aquatic animals are two examples of negative consequences. A significant portion of the increased nutrient supply to nearby water can be derived to phosphate leaching from agricultural areas, where private sewers and agriculture is two main sources.

This report is commissioned by the Water and Sewage Agency in The City of Mariehamn, Åland. The basic aim is to investigate positive or negative effects of a relocation of the sewage pipe from a wastewater treatment plant, Lotsbroverket. The environmental licence of Lotsbroverket is to be revised and The Environmental Appeal Board at Åland?s Government and Administrative Board has made demands that several possible locations in an outer water area should be examined. The present location of the sewage pipe is in Svibyviken, which has been classified as an ?inner water area?.The objective of this work is to study to which extent the nutrient loading from Lotsbroverket influence the environmental conditions in Svibyviken, and to investigate the suitability of different locations of the wastewater pipe from Lotsbroverket.The way a coastal area looks, i.e., its morphometry, determines to a large extent its ecological characteristics.

Water is the most essential resource for life. In cases where drinking water is processed from surface water it is important to ensure the raw water is of good quality, and is suitable for processing through the water treatment plant.The drinking water for Västerås is sourced from Västeråsfjärden, in the western side of Lake Mälaren. The city itself is home to marinas, ports, a wastewater treatment plant, the Svartån outlet, sewage pumping stations and stormwater outlets. Because of the negative effects these activities have on surface water quality, Mälarenergi AB is interested in relocating the raw water intake point to Granfjärden, 10 km east of Västeråsfjärden. At Granfjärden the intake point would be less exposed to the activities in Västerås, and could be placed at a greater depth, resulting in better water quality.In this Master?s thesis the water quality and the pollution risks at Västeråsfjärden and Granfjärden sites are compared.

Sewage sludge contains plant nutrients and has earlier been utilised as fertilizer to cropland. Unfortunately not only plant nutrients but also heavy metals, pathogens and organic contaminants tend to accumulate in sludge. The suitability to use sewage sludge in agriculture has therefore been subject to several discussions over the years. The Swedish food industry does no longer accept sludge as fertiliser for Swedish producers. In 1999 the Swedish parliament accepted several objectives for environmental protection. In order to prevent environmental pollution and further exploitation of the earth crust, one of these objectives confirm that phosphorous from sewage shall be recirculated to arable land.

Biogas is a renewable energy produced through anaerobic digestion, which means that organic matter is degraded by microorganisms under anaerobic conditions. The produced biogas can then be used for cogeneration, electricity, heat or upgraded to vehicle gas. Eskilstuna Energy & Environment AB has four digesters at Ekeby water sewage treatment plant, Eskilstuna. One of the biogas reactor (RK4) is equipped with a jet-mixing system while the remaining digester uses top-mixing. The mixing system is an important parameter to achieve optimum operating conditions for the process regarding gas production and degree of digestion.

Wastewater handling of private sewage systems has become an all increasing matter. In Stockholm region the 90 000 private sewage systems contribute with larger phosphorus flows to the Baltic Sea than the two biggest sewage plants in the area, Henriksdal and Käppala, contribute together, even though these two plants purify wastewater from more than one million inhabitants. When summer house areas turn into areas for permanent living ? transition areas ? the load on the existing systems increases, systems that already often are unsatisfying. In those areas it is not clear what the best system choice is; On-site systems for single households; Local collective systems or Connection to central systems.

Aim The aim of this study was to investigate the attitudes of midwives and gynaecologists at youth health clinics about their own thoughts of risks with unprotected oral sex and testing of orally contagious sexually transmitted infections (STI). The aim was also to investigate the level of knowledge of oral STIs. One further aim was to examine what they thought about the level of knowledge about oral STIs among adolescents and how common unprotected oral sex is within this group and if oral STIs/oral sex is brought up in the form of information or questions during STI-testing.Method Seventy-five youth health clinics all over Sweden were randomly chosen. A questionnaire was sent by mail to the clinics. It included questions about attitudes, knowledge about STIs and information exchange.

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. .

The access to good sanitary facilities is an important factor that elevates the experienced living standard as it improves hygiene and reduces the transmission of deseases. The ratification of the millennium goals by 189 countries demonstrates that this is an important international issue. Together the countries have taken upon themselves that the proportion of the population that lacked access to sustainable safe drinking water and sanitary facilities in the year 2000 will have been reduced by half by the year 2015. In Peru, the construction of sewage pipe networks to transport the sewage out of the direct human environment is progressing. The safety and sustainability of these systems can be questioned, since in Peru the sewage seldom receive any treatment before being emitted to a recipient. This is taking place in Picota and sorrunding villages as well. In the last 25 years several systems implementing small-scale onsite treatment have been introduced throughout Latin America in an attempt to give more people access to sustainable and safe sanitary facilities, reducing water consumption and taking advantage of the agricultural values of the sewage fractions while protecting the environment from its negative impact. In this study three different sanitary systems and the effects of different population growths were compared.

Swedish energy policy aims to increase the use of energy from renewable sources and this should be done in a safe, environmentally and sustainable manner. According to the Energy Agency the use bio-fuel increased by 73% between 1990 - 2006. Stands with high share of slash are often located on areas with high productivity which often are located on soils with poor bearing capacity. This will increase traffic on susceptible soil leading to increased ground damage. To reduce the risk of ground damage at slash-forwarding, ground protection is needed.

Swedish energy policy aims to increase the use of energy from renewable sources and this should be done in a safe, environmentally and sustainable manner. According to the Energy Agency the use bio-fuel increased by 73% between 1990 - 2006. Stands with high share of slash are often located on areas with high productivity which often are located on soils with poor bearing capacity. This will increase traffic on susceptible soil leading to increased ground damage. To reduce the risk of ground damage at slash-forwarding, ground protection is needed.

The thick shelled river mussel (Unio crassus) has a fragmented distribution in southern Sweden. It is a threatened and protected species. In both the Swedish red list and the IUCN Red List of Threatened Species Unio crassus is classified as Endangered (EN). Causes for this classification are for instance differentiated bottom substrate and deterioration in water quality. In this study, habitat preferences of Unio crassus were investigated to assist in future restoration work.

In order to avoid harmful substances ending up at the municipal sewage treatment plants, it is important to purify the wastewater at the source. One such source is the wheel washers available in many tire garages which are used to wash the wheels on our vehicles when we change between summer and winter tires. It is important to wash the wheels before storage, to extend the tires lifetime. The purpose of this study is to find a green innovative solution for reduction of emissions of heavy metals at the source, so that the sludge from the sewage treatment plants can be used as fertilizer. The target is to find a wheel wash method which leads to compliance with the guidelines for car washers, and that also provides a better washing result than with the existing method.

Lerbodaälven is a river in the municipality of Kil which, due to high phosphorus content is not meeting the requirements for good ecological status according to the Water Framework Directive. The purpose of this report is to investigate the causes for the high content of phosphorus that has been measured in Lerbodaälven between 1995-2010. Four questions will be answered in this report. 1. Does the sewage treatment work affect the phosphorus level in Lerbodaälven? The result from the time series analysis shows that the sewage treatment works have a small impact on the phosphorus level in Lerbodaälven.

Because of the increasing trends in energy consumption and increased environmental awareness, greater focus has been placed on improvement and development of renewable energy sources. An already proven and accepted method is biogas production from anaerobic digestion at municipal wastewater treatment plants.In the waste water treatment process solid material and dissolved pollutants are separated from the water, forming a sludge. The sludge is separated from the process and stabilized during anaerobic digestion or aerobic aeration. Most often, mesophilic anaerobic digestion is used. Because of degradation by microorganisms, biogas with a high content of methane is formed during the digestion.