Accretion vs. Avulsion

Even though I've been teaching the MBE for many years now, occasionally I'll come across a distinction in a question that surprises me.  It may seem rather insignificant with so much else to know in the area of Real Property, but a testable (and tested) distinction is that between avulsion and accretion.  Here's what's to know:

Both of these concepts deal with the fact that the natural effects of water upon land has the potential to change the nature and extent of the land in a way that might affect real property rights.

Accretion: A key point to keep in mind regarding accretion is that the changes to the land happen over a lengthy period of time.  For example, if you were to view over a long period of time the bank of a river or the shoreline of a lake you would notice that the water from the river or lake was depositing soil on the bank or the shoreline.  And this deposit of soil is known as accretion.  Importantly for the MBE, land formed by accretion is generally recognized to be owned by the owner of the bank or the shoreline upon which the accretion occurs.

Avulsion:  An important distinction between avulsion and accretion is one of time.  Whereas accretion takes place over a long period of time, avulsion is a sudden change in land (for example by depositing soil far downstream) brought about by water.  It may result in addition or removal of land from a bank or shoreline.  Importantly, the law generally provides that soil removed by avulsion remains the property of the original owner.

There is one other point worth noting about avulsion.  There may be a situation in which a stream acts as a boundary between two parcels of land.  Avulsion might cause that boundary to shift, and when it does the law generally holds that the landowners will retain the property that they owned before the shift in the course of the stream if the shift is due to avulsion.