Skyfallsanalys av tätorter : En jämförelsestudie mellan svenska och fem andra europeiska länders rekommendationer.

Sammanfattning

Urban areas are increasingly vulnerable to extreme rainfall events, known as cloudbursts, whichare worsened by climate change and urbanization. This study compares cloudburst modelingguidelines in Sweden and the following european countries: Norway, Denmark, Finland,Germany, and the Netherlands. Key parameters that have been studied include return periods,surface roughness (Manning’s coefficient), infiltration capacity, rainfall duration, and designrainfall profiles. The methodology combines a literature review of national guidelines and a modeling studyusing MIKE+ to simulate cloudburst scenarios in Örnsberg, Stockholm, and central Uppsala.Simulations followed Swedish guidelines for Chicago Design Storms (CDS) and were comparedwith block rain profiles from the Netherlands and Germany. Modeled return periods were 100and 250 years for Sweden and the Netherlands, while Germany included a 100-year event anda 90 mm rainfall scenario. Results show Swedish methods produce higher water depths, velocities, and discharge ratescompared to Dutch and German methods for similar return periods. Incorporating high-intensityrainfall scenarios is recommended to improve preparedness for extreme events. Sweden’sinfiltration modeling is advanced, but adopting clearer guidelines for leakage rates and soildepth, as in Denmark, could enhance accuracy. While Sweden’s surface roughness methodsare comparable to others, using more customized Manning’s values, as done in Finland and theNetherlands, may improve precision. This study offers recommendations to refine Sweden’s guidelines, strengthening preparednessfor future cloudbursts.