According to Federal Highway Administration, up to 70% of weather-related accidents occur on wet pavement or in inclement weather. Consequently, surface drainage is one of the most challenging road safety problems. Efficiency of pavement surface drainage depends on numerous factors: pavement surface geometry, rainfall intensity and duration, pavement hydraulic properties etc. In general, the most critical locations are those where the low pavement cross grades are combined with shallow longitudinal grades of the road. This is typical for inflection zones (central parts of reverse curves) in flat terrain, where gentle longitudinal grades are applied. In these areas, insufficient total pavement grades induce thicker water film, increasing the risk of aquaplaning. Most of the analytical tools for the assessment of water film depth on the pavement surface originate from distant countries, countries with the climatological conditions and even design practices differing greatly from the European ones. According to some of the most relevant analytical procedures, even the range of surface flow path lengths is inadequate in comparison to the long surface flow paths in the inflection zones of the European motorways. Moreover, climatic changes taking place in recent years must be addressed as well. This paper presents plan of investigating surface drainage and aquaplaning risks in the road inflection zone, with the final goal of augmenting and updating national standards.

aquaplaning, water film depth, surface flow path length, infection zones, climate changes