How can proper drainage affect the lifespan of asphalt pavements?

Proper drainage is critical for the longevity of asphalt pavements, and this is highlighted by the correct choice. Effective drainage systems help prevent the accumulation of water on the surface of the pavement, which can lead to several forms of damage. When water seeps into the pavement, it can weaken the underlying materials, cause the asphalt to soften, and lead to issues such as cracking, raveling, and ultimately, structural failures.

Moreover, standing water can accelerate the deterioration of the pavement surface. It can erode the materials, leading to the formation of potholes or other surface irregularities, which require costly repairs. By facilitating the prompt removal of water from the pavement surface and subgrade layers, proper drainage helps to maintain the integrity and structural support of the asphalt, thereby increasing its lifespan.

While some options suggest that drainage has no effect or even worsens pavement conditions, it’s clear that adequate drainage directly contributes to preserving the pavement's quality and reducing maintenance needs, thus extending its useful life.