Metodik för framtagande av konsekvenskartor för klimatanpassad dagvattenplanering

Sammanfattning: The extreme short-term precipitation in Sweden is expected to increase due to climate change. This means that there will be an increased risk of floodings in urban areas. Several cloudbursts during the past decade have caused major damage to communities all over Sweden with high restoration costs as a result. To prevent further damage, solutions for managing increased amounts of water are needed. However, since new measures are often costly, it is necessary to develop strategies for which geographical areas should be prioritized. There is currently no national standard for how consequence analyses of floodings should be made, and a review of previous analyses shows that the investigated consequence categories and the methods used varied greatly. The purpose of this thesis has therefore been to conduct a literature review with the aim of finding out what consequences may arise in case of a flood as well as developing a methodology for future consequence analyses using QGIS. The availability of geodata as well as the possibility of analyzing the consequences without sitespecific studies were important factors when selecting which consequences to include. The selected categories are damage costs for buildings, vehicles, roads and railroads and also consequences for vital societal functions, cultural values, road accessibility and human health. The consequences are assessed by combining data of inundation depth and water velocity with geodata of buildings and roads amongst other things. The developed methodology was applied to a modelled flood in the city of Landskrona and a script containing all the steps was created with the plugin PyQGIS to facilitate the repetition of the analysis in other cities. The results of the methods for three of the consequence categories were also compared with alternative methods which highlighted that the prioritization order of areas based on the severity of the consequences differ depending on which method is used. The work showed that it is possible to carry out general consequence analysis using geodata with national coverage but also that there is a lack of information about when consequences can be expected and how they should be assessed in relation to others.