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

• Main Author: Engström, Linda
• Format: Others
• Language: Swedish
• Published: Umeå universitet, Institutionen för ekologi, miljö och geovetenskap 2014
• Subjects: household sewage systems; eutrophication; infiltration; soil type
• Online Access: http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-96223

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.