(From Michigan Shoreline Partnership)
Shorelines change naturally over time because the shoreline is constantly being bombarded by wave or ice movement. This perpetual motion grinds and displaces soil particles which end up in the lake. In natural conditions this is typically a very slow process over a long period of time.
However, human activities have changed the balance which greatly accelerates the natural erosion processes – this is called accelerated erosion.
An eroding shoreline can be the result of natural or human elements, can be site-specific or widespread, and may have more than one cause. In addition the causes of shoreline erosion may differ because of a property’s location on the lake, water level changes and season.
Shoreline erosion is a problem for both property owners and the lake. This sedimentation changes the lake ecosystem by:
1) Covering or removing plants and bottom habitat required for fish feeding and spawning.
2) Carrying nutrients and other pollutants that may also be attached to the soil.
3) Causing the water to become turbid, or cloudy. Loss of water clarity makes feeding difficult for fish and wildlife species that rely on sight for finding their food.
There are many causes of accelerated erosion but the two most destructive actions to the lake ecosystem are:
1) Native vegetation removal – land and aquatic.
2) Hardening of the shoreline (example: seawalls).
See https://www.mishorelinepartnership.org/erosion-at-the-shoreline.html) for explanations of these and potential solutions.