How does proper drainage impact highway construction?

Answer: B — It prevents erosion and maintains road integrity

Proper drainage is crucial in highway construction as it plays a significant role in preventing erosion and maintaining the integrity of the road. Effective drainage systems are designed to manage surface and subsurface water, which helps to divert water away from the roadway and its supporting structures. When water accumulates on or beneath the road surface, it can weaken the soil and sub-grade materials, leading to issues such as pavement cracking, subsidence, and ultimately road failure. By ensuring that water is properly drained, the highway can withstand the various stresses it experiences from traffic and environmental factors, thereby extending its lifespan and promoting safety for all users. In contrast, while some elements of drainage planning may initially appear to complicate maintenance, the overall benefits provided by effective drainage systems far outweigh these concerns. Additionally, though proper drainage can involve investment, its ability to prevent costly repairs in the future makes it a cost-effective measure over time. Lastly, unlike the idea that drainage is irrelevant, it is a fundamental aspect of highway durability that must be addressed to ensure long-term performance and safety.