What does the term "surface runoff" describe in earthworks?

The term "surface runoff" refers specifically to the flow of water that occurs when excess rainwater, melting snow, or other sources of water cannot be absorbed into the ground and instead flows over the surface of the land. This phenomenon often takes place in areas where the soil is saturated or where the ground is impervious, such as in urban settings with concrete or asphalt. Understanding surface runoff is crucial in earthworks because it affects erosion, sediment transport, and water management practices.

In contrast, the other choices focus on different aspects of the water cycle and soil interactions. For instance, filtration through soil describes how water percolates downward, while absorption refers to how soil takes in water. Evaporation, on the other hand, involves water changing from liquid to vapor and does not directly relate to flow over the surface of the land. Therefore, the correct interpretation of "surface runoff" is clearly aligned with the concept of water moving across the earth's surface.