Aquaplaning risk assessment in Portuguese road design guide

For a long time, the aquaplaning phenomenon has been acknowledged to cause serious road accidents, during heavy rainfall, given specific vehicle and road conditions. Accident statistics confirm that during adverse weather conditions the rate of crashes increases. Portuguese road concession contracts require accident rates to be monitored and define payment adjustment factors in relation to accident rate variation in comparison with data from previous years. However, there are no defined guidelines to assess the risk of aquaplaning and how to deal with it. A discussion of the definition of guidelines to assess aquaplaning risk at project level in Portugal, and the recommended countermeasures, considering other world administrations' analysis methodologies and published research results of the past 50 years are presented herein. The critical analysis highlights the conditions contributing to failure and the share of responsibility between the road administration and the driver.