👉 Overfilling is a term used in environmental science to describe the accumulation of sediment or other material within a natural or artificial surface. It occurs when excess water, sand, or other substances are deposited on top of the surface of an existing layer of soil, rock, or other material that is not being drained or cleared away. Overfills can be caused by various factors such as erosion, weathering, or mechanical forces such as pressure or force applied to the surface. They can also result from improper