Long-term effects of Erosion on stone caused by a stream bed in Watkins Glen, NY

Erosion is the natural phenomenon of surface forces, mainly wind or water, gradually wearing away at the soil and stone on Earth’s surface. It is one of the primary geological processes that gives Earth its mountains and canyons. Water is one of the most significant contributors to the progression of erosion.

As water naturally flows downwards, rivers and streams intermingle with one another to form drainage basins. As rain falls on the ground, the earth will eventually become saturated which leaves the remaining rainfall to move over the surface. This movement picks up dust, dirt, and debris along the way and carries the material along with the water flow into the drainage basin. Once the water reaches rivers and streams, the picked up debris is carried away leaving only pebbles and rocks. These small remnants are constantly hit against one another by the force of the river resulting in them progressively becoming smaller and smaller. This is how rock formations along rivers or in canyons are often formed over a long period of time.

However, as this erosion continues over time the ground itself can become more unstable to walk on or in other cases incredibly steep. These effects can develop more quickly when an abnormal amount of rain is dropped onto a region. For example, the Shenandoah National Park receives an average of 3-4 inches of rain per month. In extreme cases, a single high-impact storm has the ability to drop anywhere from 10-15 inches over the span of a few days. This can, and often does, cause flooding that accelerates the normal effects of erosion and causes damage to the trails in its way. As the ground becomes oversaturated, this also makes it easier for strong winds to uproot trees which causes more damage.