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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Model testing and analysis of vortex drop shaft

Balah, M. I. A. January 1984 (has links)
No description available.
2

Enskilda avlopp i Nordmalings kommun : Status, skyddsnivåer och teknikval i olika jordartsområden

Engström, Linda January 2014 (has links)
The purpose of this study was to describe a) the status of the household sewage systems in the municipality of Nordmaling, b) to suggest areas in which a higher level of protection would be required and c) to investigate which type of technological choice was appropriate for which type of soil. A survey was used to investigate the status of the household sewage systems. The status was judged mainly on the age and treatment of water. Protected areas, the ecological status and data for phosphorus and nitrogen were used to locate areas in need of a higher protection. Map data from the Geological Survey of Sweden was used to identify common soil types in Nordmaling. Subsequently, the map was complemented and verified with a field investigation. In a next step, characteristics of the soil types were compared to the requirements of four different sewage treatment technologies; infiltration, constructed infiltration, incinerator toilets and household sewage plants. The study shows that the household sewage systems in Nordmaling are in general not in a good condition. Almost 70 % of the sewage systems are older than 20 years and their function is likely not sufficient. The study suggests that the following areas should be included in the list of objects with high protection: Lögde- and Öre river, Kronören, Järnäs peninsula, waters with an ecological status below “good” and the protected water resources. Except for infiltration, all sewage treatment technologies were assumed to give appropriate results for all soil types.
3

Enskilda avlopp: statuskontroll samt kommuners tillsynsarbete

Nieminen, Per January 2015 (has links)
Water is essential for our daily life. Despite this, much of our water has become polluted and nutrient-enriched. One main factor contributing to the problem are private sewers. In total, there are nearly 1 million private sewers in Sweden, which represent one of the largest point sources of nitrogen and phosphorus. A survey was carried out to investigate the status of private sewers at Källsjön, Sollefteå municipality. In addition, four municipalities around Sollefteå have been interviewed about the implementation of legislation concerning private sewers. The study shows that sewers around Källsjön are seemingly in relatively good condition. However, 36% of the polled property owners have drains that are over 20 years old, and the function of these drains can be questioned. Interestingly, many of the surveyed property owners do not even know how old their drains are and what type of facility they have. Three of four interviewed municipalities are currently not performing any active control of private sewers. All municipalities provided information to property owners regarding current legislation. The study suggests that municipalities should act proactively to establish comprehensive inventories, a first step towards raising the standard of the individual sewers.
4

Kraven på ägare till minireningsverk skiljer sig åt mellan olika kommuner

Stenbacka, Nina January 2015 (has links)
Discharge of inadequately treated waste water containing nutrients such as phosphorus and nitrogen as well as organic matter and bacteria is associated with a risk of eutrophication and contamination. The Swedish government has decided upon several Environmental Quality Objectives aiming to reduce the emissions of nutrients to water bodies. In Sweden, there are between 675 000 to 1 000 000 on-site sewage systems. Recent studies have shown that the function of small sewage treatment plants is in many cases insufficient. To prevent this regular service and supervision by a professional is needed. The focus of this study are small sewage treatment plants which use a technique where mechanical, chemical and/or biological reduction of pollutants is being used in the same facility to reduce nutrients in household wastewater. The aim of the study is to investigate how different municipalities ensure that small sewage treatment plants fulfill the requirements and reduce pollutants as efficient as the manufacturers claim. To do this, a survey was carried out, leading to a data-set that is covering more than 90 municipalities. The results show that many municipalities lack resources to ensure that small sewage treatment plants work properly. Operation and maintenance of the plants is an important issue, and should be given much more attention. Therefore the municipalities should request more documentation from the owners both before and after installation to make sure that the small sewage treatment plant can fulfill the required standard. About half of the municipalities demand that the owners acquire some kind of service agreement with the manufacturer.  If small sewage treatment plants should be a wastewater treatment solution that we can rely on in the future, there is a need of evaluating and analyzing these facilities more systematically.
5

Jämförelse mellan våtkompostering och andra VA-system i omvandlingsområden : en fallstudie i Norrtälje kommun. / Comparison between liquid composting and other waste water systems in transition areas : a case study in Norrtälje municipality

Tibbelin, Emelie January 2010 (has links)
<p>Eutrophication of the Baltic Sea and Swedish lakes remains a major problem despite many years of effort to reduce the emissions of nutrients. One major source is waste water systems, especially private sewage systems. These sewages accounts for a very large share of nutrients per capita in comparison with citizens connected to larger sewage treatment plants. Norrtälje community has the greatest number of private sewage systems in Sweden. Discharges of nutrients, especially phosphorus, to the Baltic Sea from these sewage systems are significant. That is why Norrtälje is working actively to improve the standard of these sewage systems.</p><p>The purpose with this Master Thesis was to compare from an environmental and cost perspective, different sewage systems in an area of Norrtälje. One of these sewage systems was liquid composting. To make this easier a tool called VeVa, which is an instrument for assessment of water and sewage systems in transition areas, was used. Since liquid composting was not included in VeVa in the beginning of the study one purpose was also to implement this option in the tool. Another objective of the work was to evaluate whether liquid composting is still a good sewage options in the future. The result of this study is based on a literature review, contact with Norrtälje community and modeling in VeVa.</p><p>The four sewage systems that where included in the study where connection to a large scale waste water treatment plant, local sewage treatment plant and liquid composting. The fourth system was a new construction of the already existing private sewage system in the area. This system was a sand filter system with a phosphorus trap and a separation and collection of toilet water.</p><p>Results from the study showed that all systems, with some exceptions for local wastewater treatment plant, can meet the Swedish Environmental Protection Agency high demand of phosphorus and nitrogen reduction for small sewage systems. All systems in the study, except for sand filter with phosphorus traps, have a high reversal potential of phosphorus. However it is only the liquid compost that can recycle nitrogen back to arable land to a greater extent. A comparison between manure sludge from waste water treatment plants and liquid composts showed that the liquid composts had a much lower level of cadmium content and higher proportion of plant available nutrients. The energy use for these systems varied widely where connection to a large scale wastewater treatment plant have the highest, while the liquid compost have the lowest energy use. The cost analysis showed that a municipal sewage treatment plant is the most expensive and liquid composting system is the next most expensive system. However, the differences in cost between the studied systems are not particularly large when uncertainties in the input are accounted. The conclusions of this Master Thesis were that liquid composting is a good sewage solution, especially when recycling of nutrients is an important factor. However there are important social and economic considerations that must be taken into account when deciding which sewage system should be implemented.</p> / <p>Övergödning av Östersjön och andra svenska vattendrag är ett stort miljöproblem som uppkommer av antropogena utsläpp av näringsämnen. En betydande källa för dessa utsläpp härrör från avloppsrening, i synnerhet från enskilda avlopp. Enskilda avlopp utgör en oproportionerligt stor källa av främst fosforutsläpp jämfört med större reningsverk räknat per capita. Norrtälje kommun är den kommun i Sverige som har flest enskilda avlopp och detta gör att utsläppen av näringsämnen till Östersjön är betydande. Den dåliga ekologiska statusen i stora delar av kommunens vattenområden har inverkat till att kommunen arbetar aktivt med att förbättra avloppsstandarden i dessa problemområden. År 2005 byggdes en våtkompostanläggning i Norrtälje vars syfte var att producera gödsel av avloppsvatten för att på så sätt ta vara på avloppsvattnets näringsinnehåll. Denna anläggning har lett till ett ökat intresset för system som har stor återföringspotential av växtnäringsämnen och funderingar på ytterligare en våtkompostanläggning i kommunen diskuteras i dagsläget.</p><p>Syftet med detta examensarbete var att studera fyra olika avloppsalternativ, där våtkompostering var ett alternativ, för ett fallstudieområde i Norrtälje. Som hjälpmedel för att utföra miljö- och kostnadsanalyser användes VeVa-verktyget som är ett verktyg för miljö- och kostnadsbedömningar för VA-system i omvandlingsområden. Eftersom våtkompostering inte ingick i VeVa vid detta examensarbetes början var också ett syfte att implementera detta avloppssystem i verktyget. Ett annat syfte var att göra en bedömning om våtkompostering är ett bra avloppssystem även i framtiden. Resultaten i denna studie bygger på en litteraturstudie, myndighetskontakt och modellering i VeVa. De avloppssystem som jämfördes i studien var anslutning till kommunalt avloppsreningsverk (ARV), lokalt avloppsreningsverk, våtkompostering och nyanläggning av samma enskilda system som i dagsläget finns i fallstudieområdet. Det sistnämnda systemet är en kombination av markbädd med fosforfälla samt sluten tank och markbädd.</p><p>Resultatet från studien visar att alla systemen med viss reservation för lokalt avloppsreningsverk uppfyller Naturvårdsverkets höga skyddsnivå för fosfor och kväve vilket är 90 % respektive 50 %. Alla system har en hög återföringspotential av fosfor men det är endast våtkompostsystemet som kan återföra kväve i större omfattning. Jämförelsen mellan slam från avloppsreningsverk och våtkomposterat avloppsavfall visade att våtkompost har mycket lägre kadmiumhalt samt högre andel växttillgänglig näring. Energianvändningen varierar mycket mellan systemen där anslutning till kommunalt avloppsreningsverk har högst förbrukning, medan våtkompostsystemet har lägst. Kostnadsanalysen visar att anslutning till kommunalt avloppsreningsverk är dyrast och våtkompostsystemet hamnar på andra plats. Dock är skillnaden mellan de studerade systemen inte speciellt stor när osäkerheter i indata beaktats. Slutsatsen i detta arbete är att våtkompostering är en bra avloppslösning, speciellt när kretsloppsanpassning är en viktig del, dock finns det viktiga sociala och ekonomiska aspekter som måste vägas in vid beslut om avloppssystem.</p>
6

Jämförelse mellan våtkompostering och andra VA-system i omvandlingsområden : en fallstudie i Norrtälje kommun. / Comparison between liquid composting and other waste water systems in transition areas : a case study in Norrtälje municipality

Tibbelin, Emelie January 2010 (has links)
Eutrophication of the Baltic Sea and Swedish lakes remains a major problem despite many years of effort to reduce the emissions of nutrients. One major source is waste water systems, especially private sewage systems. These sewages accounts for a very large share of nutrients per capita in comparison with citizens connected to larger sewage treatment plants. Norrtälje community has the greatest number of private sewage systems in Sweden. Discharges of nutrients, especially phosphorus, to the Baltic Sea from these sewage systems are significant. That is why Norrtälje is working actively to improve the standard of these sewage systems. The purpose with this Master Thesis was to compare from an environmental and cost perspective, different sewage systems in an area of Norrtälje. One of these sewage systems was liquid composting. To make this easier a tool called VeVa, which is an instrument for assessment of water and sewage systems in transition areas, was used. Since liquid composting was not included in VeVa in the beginning of the study one purpose was also to implement this option in the tool. Another objective of the work was to evaluate whether liquid composting is still a good sewage options in the future. The result of this study is based on a literature review, contact with Norrtälje community and modeling in VeVa. The four sewage systems that where included in the study where connection to a large scale waste water treatment plant, local sewage treatment plant and liquid composting. The fourth system was a new construction of the already existing private sewage system in the area. This system was a sand filter system with a phosphorus trap and a separation and collection of toilet water. Results from the study showed that all systems, with some exceptions for local wastewater treatment plant, can meet the Swedish Environmental Protection Agency high demand of phosphorus and nitrogen reduction for small sewage systems. All systems in the study, except for sand filter with phosphorus traps, have a high reversal potential of phosphorus. However it is only the liquid compost that can recycle nitrogen back to arable land to a greater extent. A comparison between manure sludge from waste water treatment plants and liquid composts showed that the liquid composts had a much lower level of cadmium content and higher proportion of plant available nutrients. The energy use for these systems varied widely where connection to a large scale wastewater treatment plant have the highest, while the liquid compost have the lowest energy use. The cost analysis showed that a municipal sewage treatment plant is the most expensive and liquid composting system is the next most expensive system. However, the differences in cost between the studied systems are not particularly large when uncertainties in the input are accounted. The conclusions of this Master Thesis were that liquid composting is a good sewage solution, especially when recycling of nutrients is an important factor. However there are important social and economic considerations that must be taken into account when deciding which sewage system should be implemented. / Övergödning av Östersjön och andra svenska vattendrag är ett stort miljöproblem som uppkommer av antropogena utsläpp av näringsämnen. En betydande källa för dessa utsläpp härrör från avloppsrening, i synnerhet från enskilda avlopp. Enskilda avlopp utgör en oproportionerligt stor källa av främst fosforutsläpp jämfört med större reningsverk räknat per capita. Norrtälje kommun är den kommun i Sverige som har flest enskilda avlopp och detta gör att utsläppen av näringsämnen till Östersjön är betydande. Den dåliga ekologiska statusen i stora delar av kommunens vattenområden har inverkat till att kommunen arbetar aktivt med att förbättra avloppsstandarden i dessa problemområden. År 2005 byggdes en våtkompostanläggning i Norrtälje vars syfte var att producera gödsel av avloppsvatten för att på så sätt ta vara på avloppsvattnets näringsinnehåll. Denna anläggning har lett till ett ökat intresset för system som har stor återföringspotential av växtnäringsämnen och funderingar på ytterligare en våtkompostanläggning i kommunen diskuteras i dagsläget. Syftet med detta examensarbete var att studera fyra olika avloppsalternativ, där våtkompostering var ett alternativ, för ett fallstudieområde i Norrtälje. Som hjälpmedel för att utföra miljö- och kostnadsanalyser användes VeVa-verktyget som är ett verktyg för miljö- och kostnadsbedömningar för VA-system i omvandlingsområden. Eftersom våtkompostering inte ingick i VeVa vid detta examensarbetes början var också ett syfte att implementera detta avloppssystem i verktyget. Ett annat syfte var att göra en bedömning om våtkompostering är ett bra avloppssystem även i framtiden. Resultaten i denna studie bygger på en litteraturstudie, myndighetskontakt och modellering i VeVa. De avloppssystem som jämfördes i studien var anslutning till kommunalt avloppsreningsverk (ARV), lokalt avloppsreningsverk, våtkompostering och nyanläggning av samma enskilda system som i dagsläget finns i fallstudieområdet. Det sistnämnda systemet är en kombination av markbädd med fosforfälla samt sluten tank och markbädd. Resultatet från studien visar att alla systemen med viss reservation för lokalt avloppsreningsverk uppfyller Naturvårdsverkets höga skyddsnivå för fosfor och kväve vilket är 90 % respektive 50 %. Alla system har en hög återföringspotential av fosfor men det är endast våtkompostsystemet som kan återföra kväve i större omfattning. Jämförelsen mellan slam från avloppsreningsverk och våtkomposterat avloppsavfall visade att våtkompost har mycket lägre kadmiumhalt samt högre andel växttillgänglig näring. Energianvändningen varierar mycket mellan systemen där anslutning till kommunalt avloppsreningsverk har högst förbrukning, medan våtkompostsystemet har lägst. Kostnadsanalysen visar att anslutning till kommunalt avloppsreningsverk är dyrast och våtkompostsystemet hamnar på andra plats. Dock är skillnaden mellan de studerade systemen inte speciellt stor när osäkerheter i indata beaktats. Slutsatsen i detta arbete är att våtkompostering är en bra avloppslösning, speciellt när kretsloppsanpassning är en viktig del, dock finns det viktiga sociala och ekonomiska aspekter som måste vägas in vid beslut om avloppssystem.
7

Övergödning i Stavbofjärdens tillrinningsområde : En utvärdering av genomförda insatser för minskad näringsbelastning från enskilda avlopp och jordbruk

Hoflin, Malin January 2012 (has links)
Syftet med denna studie har varit att utvärdera och granska den första tidsperioden av det unika projektet Enskilda avlopp i kretslopp samt åtgärder som genomförts inom jordbruket för minskad näringsbelastning i Stavbofjärden tillrinningsområde i Södertälje kommun. Utmaningar med projektet redovisas också för att undersöka möjligheten för andra kommuner att ta efter initiativet. För att uppnå syftet har litteraturstudier och semistrukturerade intervjuer genomförts. Arbetet är en fallstudie av utvärderande karaktär och har genomförts i Stavbofjärdens tillrinningsområde. Problemen med övergödning är stora i Stavbofjärdens tillrinningsområde och idag arbetar man aktivt för att minska näringsbelastningen. Sedan tre år tillbaka pågår projektet Enskilda avlopp i kretslopp för att försöka minska övergödningsproblematiken och möjliggöra återföring av näringsämnen till åkermark. Att avlopp kretsloppsanpassas innebär att klosettvatten samlas i en sluten tank skilt från bad, disk och tvättvatten (BDT- vatten). Därefter behandlas fraktionen för att göra den fri från smittämnen, bearbetad näring sprids slutligen på åkermark. I anslutning till detta har aktörer inom jordbruket arbetat med att försöka sluta kretsloppet och minska näringsutsläppen till Stavbofjärden. Flertalet åtgärder har genomförts under projektets första fas, bland annat har en kretsloppspolicy antagits, en lokal behandlingsanläggning har byggts och näringsämnen har börjat återföras till åkermark. Tydliga strukturella förändringar har skett under de första åren av projektet, framförallt har samarbetet mellan olika aktörer i tillrinningsområdet stärkts. Förutsättningarna för att nå en förbättrad vattenkvalitet i Stavbofjärden förbättras i och med genomförda och planerade åtgärder. Däremot uppstår en rad utmaningar i och med att avloppsfraktioner sprids på åkermark. Intervjuer och litteraturstudier har visat att användning av slam från reningsverk på åkermark inte är en helt okontroversiell fråga, mestadels på grund av en oro för eventuella effekter av de hormoner och läkemedel som kan förekomma i fraktionerna. Andra utmaningar är att byte av avloppssystem innebär en hög investeringskostnad och att människor ofta känner sig otrygga vid stora förändringar. Alla deltagande aktörer i projektet hänvisar till det faktum att människans avfall måste hamna någonstans och att det är betydligt bättre att lägga avfallet på jorden än att det läcker ut i vattnet eftersom det finns betydligt fler nedbrytande bakterier i jorden än i vatten. / The purpose of this study was to evaluate and examine the first period of the unique project Enskilda avlopp i kretslopp and actions implemented in the agriculture sector to reduce nutrient loading in Stavbofjärden. The idea was to provide an overall assessment of the current situation and discuss the possible future effects of the work. Challenges of the project are also discussed to examine the possibility for other communities to follow the initiative. To achieve the purpose, a study of literature and semi-structured interviews were conducted. The work is a case study of the evaluative nature and has been implemented in Stavbofjärdens catchment area.  Today several actors in Södertälje kommun are working actively to reduce nutrient loading in Stavbofjärdens catchment area. For the past three years, the project has been carried out in order to reduce eutrophication and enable recycling of nutrients to cropland. Within the project framework toilet water is collected in a closed tank separate from the bath, sink and wash water, the fraction is then processed in a facility and spread on farmland. In connection with this, the agriculture sector tries to close the cycle and reduce nutrient discharges to Stavbofjärden. Several measures have been implemented during the project's first phase, a recycling policy has been adopted, a local treatment facility has been built and nutrients have begun return to arable land. Distinct structural changes have occurred in the first years of the project, in particular, cooperation between different actors in the catchment area strengthened. The prospects for achieving improved water quality in Stavbofjärden increasing with the implemented and planned measures. The project also raises a number of challenges. Interviews and literature studies have shown that the use of sludge on farmland is not an entirely uncontroversial issue, mostly because of a concern about the possible effects of hormones and medicine which may occur in factions. Other challenges are that the replacement of sewer means a high investment cost and that people feel insecure when major changes happens. All actors involved in the project refers to the fact that human waste has to end up somewhere, and that it is much better to put the waste on soil than it leaks out in the water because there are far more degrading bacteria in the soil than in water.
8

Tillsynsmetoder riktade mot minireningsverk

Törnqvist, Elin January 2018 (has links)
Sweden today have about 700 000 sewer systems, among which half of the plants are considered inefficient. The wastewater contains nutrients such as phosphorus and nitrogen, which in turn contribute to the eutrophication of waters. According to the Water Authorities, there are 650 waters in the northern district of the Baltic Sea that suffers from eutrophication. Close by these waters it is common with smaller treatment plants for sewages. It is up to the monitoring authority to decide which degree of purification the plants need and to supervise. There are different monitoring methods of small treatment plants and it is up to each municipality to choose their way, which means that monitoring is very different between different municipalities. The purpose of this study is to identify how different municipalities preform monitoring. It is aimed to investigate the need of a more effective monitoring for Norrtälje Municipality and to see if any of the methods from the other municipalities may be suitable. Examination has been done through participation in sampling projects, survey and compilation of data from VISS. The survey showed that monitoring practices in the municipalities differ greatly since the number of smaller treatment plants and resources differs. Data from VISS shows that the need for monitoring is high since 68 waters in Norrtälje won´t reach good status until 2021. Previous projects show that the authorities find it hard to do the sampling by themselves but there is a high demand for such methodology.
9

Dimensionamento hidrÃulico de redes coletoras de esgoto sanitÃrio usando o critÃrio de atendimento crÃtico. / Hydraulic design of sanitary sewage systems using the criteria of Critical Care.

Alessandro de AraÃjo Bezerra 25 November 2011 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Redes coletoras de esgoto sÃo elementos importantes para garantir a saÃde, o bem-estar social e proteÃÃo ao meio ambiente, entretanto, elaborar projetos para desenvolver essas estruturas implica em atividades com etapas muito onerosas e repetitivas. Assim, com o objetivo de reduzir o tempo gasto, garantindo a qualidade e eficiÃncia do projeto final, os programas computacionais vÃm ganhando espaÃo e importÃncia em projetos de engenharia. O programa UFC9, objeto desenvolvido neste trabalho, à um aplicativo desenvolvido nas linguagens AutoLISP, VBA (Visual Basic for Applications) e VB (Visual Basic), o qual possui recursos grÃficos para auxiliar no desenvolvimento de projetos dentro do ambiente AutoCAD. Este trabalho foi desenvolvido para auxiliar no desenvolvimento de projetos de redes coletoras de esgoto nos elementos relacionados a desenho, dimensionamento, quantitativos e orÃamento destes importantes elementos de um sistema de esgotamento sanitÃrio. Em se tratando de desenhos, o software objeto deste trabalho auxilia no traÃado da rede coletora e geraÃÃo de perfis, no caso do dimensionamento, o software permite o dimensionamento da rede considerando ou nÃo o atendimento crÃtico, ou seja, o atendimento de casas em cotas baixas. Outra consideraÃÃo importante à a possibilidade de prever obstÃculos na rede, evitando, assim, problemas durante a execuÃÃo da obra. As planilhas de dimensionamento e de orÃamento geradas pelo programa podem ser exportadas para o Excel, facilitando a elaboraÃÃo de memoriais descritivos e de cÃlculos, alÃm de permitir alteraÃÃes ou complementaÃÃes nos orÃamentos das redes gerados pelo software. / Sewage systems are important elements to ensure the health and social welfare, however, elaborating projects to develop these structures involves activities with very onerous and repetitive steps. Thus, with the objective to reduce the time spent, ensuring quality and efficiency of the final project, computer programs have been gaining space and importance in engineering projects. The program UFC9 is an application developed in languages AutoLISP, VBA (Visual Basic for Applications)and VB (Visual Basic), which has graphics resources to assist in developing projects within the AutoCAD environment. This work was developed to assist in developing projects of sewage systems in the elements related to design, sizing, quantification and budget for these important elements of a sanitary sewage system. In the case of drawings, this software helps in tracing the collection network and profiling, in the case of dimensioning, the software allows the network dimensioning considering or not the critical coverage, in which they are located houses below the pipes. Another important consideration is the possibility of setting obstacles in the network, thus avoiding problems during the execution of the work. The dimensioning worksheets and budget generated by the program can be exported to Excel, facilitating the development of descriptive memorials and calculations, and allow for changes or additions in the budgets of networks generated by the software.
10

Tillsyn av små avlopp : Bättre stämma i bäcken än i ån

Wijk, Anders January 2020 (has links)
Water is crucial for all life on this planet. Despite this much of our aquatic environments have become affected by pollution and nutrient-loading. One large contributor to the problem is privately owned sewers, also called on-site sewage systems. Currently there are approximately 691 000 on-site sewage systems in Sweden, which carry the infamous distinction of representing one of the largest point sources of phosphorus and nitrogen. Furthermore roughly 180 000 of these sewers are by legal definitions unlawful, because of substandard wastewater treatment. The purpose of this study was to investigate how Sweden’s 290 municipalities conduct their supervision towards privately owned sewages and what inventory and administration rates they have. A hypothesis was there should be a correlation between municipalities’ inventory and administration rates. The study was conducted by a web-survey sent out to all municipal environmental and health offices. The results show a majority of the municipalities have an inventory ongoing, or have already conducted one. Administration and inventory rates at which on-site sewage systems are being controlled are rather low, numbering 3.1 respectively 3.6 percentages per year. Surprisingly there was also a low correlation between the inventory and administration rates, with an r-value of only 0.29 (r2 ≈ 0.085). Overall, the results indicate a need to increase oversight of inadequate and non-regulatory on-site sewage systems if we are to meet our national environmental goals and our global sustainable development goals.

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