What is essential when determining the slope gradient?

The slope gradient is an important aspect of earthworks and surveying because it directly influences drainage, erosion, and the stability of structures built on or within the slope. The correct way to determine slope gradient is by calculating the ratio of vertical rise to horizontal run. This ratio provides a concise mathematical representation of how steep the slope is, which is essential for various engineering and construction applications.

The vertical rise refers to the change in elevation from one point to another, while the horizontal run indicates the distance over which that elevation change occurs. By expressing slope as a ratio, it becomes easier to communicate and standardize the measurement for practical use in fieldwork and design.

The other options, while relevant in certain contexts, do not directly contribute to the determination of slope gradient. The height of structures may influence local slope considerations but is not a factor in calculating slope itself. Similarly, the amount of precipitation can affect stability and erosion but does not define the gradient of a slope. The depth of excavation pertains mostly to the extent of earth removal rather than the measurement of slope itself. Thus, the most accurate and relevant measure of slope gradient is indeed the ratio of vertical rise to horizontal run.