In the NVF Road Design webinar on 18 June 2025, Matthias Borris from Trafikverket (Swedish Transport Administration) presented a case study about how a very local, extreme rainfall event caused serious damage to the E45 highway north of Gothenburg in July 2024.
The presentation explains how heavy rain, steep slopes, low soil infiltration, and earlier road construction choices (such as light filling materials and too small culverts) made the road more sensitive to flooding and damage.
The webinar includes:
- Weather and water conditions during the event
- Weak points in the road structure
- Traffic effects: full road closure for 2 days, and one lane closed for 9 months
- Lessons learned about drainage, construction risks, and how to make roads stronger in future.
Recording also available on the Road Design working group’s Public Materials page, where you can also find the previous webinar recordings Climate Change Adaptation by Gunnel Göransson and Rethinking Our Roads by Elina Kalliala.