What defines a Land-Disturbing Activity (LDA)?

A Land-Disturbing Activity (LDA) is defined as any manmade change to the land surface that affects the runoff characteristics of that land. This definition encompasses a broad range of activities that modify the terrain, including construction, excavation, grading, and even certain landscaping activities. The key aspect of LDA is the impact on the hydrology of the area, particularly regarding how water flows across the surface and how it infiltrates into the ground. By changing the surface characteristics, such as texture, slope, and permeability, these activities can significantly alter water runoff patterns, potentially leading to erosion or increased sedimentation in nearby water bodies.

While other activities like planting vegetation, excavation in urban areas, and clearing structures for construction may involve some degree of land disturbance, they do not inherently change the runoff characteristics in a holistic sense. For instance, planting vegetation can be part of a stabilization effort that helps improve runoff conditions. Therefore, the fundamental concept of a Land-Disturbing Activity is rooted in its effect on runoff and hydrology, making the chosen definition the most accurate.