What type of asphalt is designed to facilitate water drainage?

Open-Graded Asphalt Friction Course is specifically designed to facilitate water drainage on roadways. This type of asphalt features a porous structure that allows rainwater to drain through its surface. By incorporating a larger void space within the mix, it reduces the risk of hydroplaning, enhances traction in wet conditions, and helps to improve overall safety for motorists during inclement weather.

Unlike dense graded asphalt, which is more compact and does not provide significant drainage features, or warm-mix asphalt, which is formulated primarily for better workability and reduced emissions during production, open-graded asphalt prioritizes drainage capabilities. The ultra-thin bonded wearing course is also not intended primarily for drainage but instead serves to enhance the surface texture and improve ride quality. Therefore, open-graded asphalt stands out as the correct choice for facilitating effective water drainage on road surfaces.