Climate change causes increased occurrence of high water flows and elevated water tables in many freshwater systems. This increases the stress on structures for road dewatering and drainage. Many culverts, ditches, etc have limited capacity. The stress will increase with increasing frequency of heavy storms and high water flows. The Swedish Transport Administration (STA) has limited knowledge of the capacity of their draining structures. Maintenance of the structures and routines for their follow-up are insufficient. Floods may cause critical situations to road constructions. Changes in frost—thaw cycles can also add stress to drainage systems and road constructions. There is a great demand for securing a continuous function of the drainage systems. To this end, decision-makers will need a reinforced scientific knowledge base. Aim of this book: to produce a scientifically well-founded suggestion on a cost-efficient adaptation of road drainage and dewatering systems to climate change including more frequent floods.