Accretion Real Estate

The term accretion is used in real estate law to refer to an increase of land due to the accumulation of soil on the shoreline of a lake, stream, or the sea. While accretion is a gift bestowed on landowners by Mother Nature, land can also decrease in size through erosion and avulsion. To explore this concept, consider the following accretion real estate definition.

Definition of Accretion Real Estate


  1. An increase to land by natural growth or deposits due to moving water of a lake, stream, or the sea.


1605-1615       Latin accrēscere  (to grow)

What is Accretion Real Estate

Properties that border bodies of water, such as lakes, rivers or streams, and the ocean, are subject to changes in that line from erosion, or from deposits of dirt and sand. Water, over time, acts almost like a living thing, as it moves and affects the land around it. This is a powerful force, considering that the Grand Canyon was carved by the force of moving water over thousands of years.

Accretion in real estate works on a somewhat smaller scale for most land owners, slowly increasing or decreasing the actual amount of land mass owned. The three ways that moving water can affect a property’s geography include accretion, avulsion, and reliction. Just how such changes affect the ownership and value of an affected property varies by state, but there are some rules generally adhered to.


Accretion is the gradual increase of land mass by the washing up of silt or soil, caused by the movement of a neighboring body of water.

For example:

Arnold’s farm boarders a large lake, which is enjoyed by tourists and locals alike throughout the summer seasons. Arnold’s grandfather owned the land before passing it down to Arnold, and he recalls spending time as a boy at the lake over which the large house looked.

The shoreline, as Arnold remembers it, was much closer to the house and immediate yard. In this example of accretion in real estate, the lake has slowly deposited silt and soil with each wave that surfs the shore.

While, in this example of accretion, Arnold is considered to be the owner of the increased land surface left behind over the past half century or so, there is a limit. Should that accretion land mass happen upon an existing right of way, the land owner has no more claim to the area than he had before the accretion occurred.


Avulsion is a sudden, obvious change in the land caused by water. For instance, during a storm, a river may swell, the water running higher on its banks than normal. This can wash way large chunks of unstable soil, carrying it downstream.

For example:

Neal and John bought a small piece of property next to a medium-sized tributary of a large river. The pair had caught gold-panning fever, and planned to pan on their own little slice of the shore. They built a small one-room cabin to stay in on weekends, and had moderate success pulling small bits of gold out of the stream.

One day, as a large storm brought deluge after deluge, the swollen stream weakened the banks, and a large chunk of Neal’s and John’s parcel joined the rushing waters. The laws regarding avulsion of property generally provide that the actual soil that is broken off remains the property of the original owner.

In this case, had the men been finding gold in the very location from which the large chunk of land had been washed away, they might want to pursue where it landed (assuming it remained at least partially intact).

While the law may support their continued ownership of the soil, they may have difficulty proving the soil found on someone else’s stream bank was originally theirs, and then there would be the expense involved in collecting it and trucking it back to their parcel.


Reliction is, in a way, the opposite of accretion, in that the land area is gradually increased because the waterline is receding, or moving farther out. Reliction may also refer to a change in property boundaries resulting from a river’s or stream’s change of course over time. In general, property gained by reliction belongs to the owner of the property.

For example:

Millie’s family has owned a home that butts up against a small river for generations. Over the past several decades, the water has moved soil, taking some with it on its journey, and leaving some further down the way. This has gradually pushed the river out of its course, changing the property lines on both sides.

The sandy riverbank on which the family had been holding family picnics and get-togethers has grown wider over the years, and the family’s property line with it. Because the land gained by reliction belongs to the owner of the property adjacent to the water, commissioning a new survey of the property might result in an increase of the property’s value.

Accretion Real Estate Example on Topsail Island

There is a 26-mile long coastal barrier island off the coast of North Carolina called Topsail Island. Topsail Island is a sanctuary for sea turtles, and its beautiful beaches attract visitors in droves. An interesting thing has been happening on the southern end of the island, as accretion has added additional land at the surprising rate of about 100 feet per year.

Accretion has the power to add significant acreage. In this example of accretion, the southern tip of Topsail Island gained as much as 300 acres of new land in about 20 years. In fact, according to historic records, the inlet adjacent to the island has migrated about 6 miles since its original recorded location in 1738.

Related Legal Terms and Issues

  • Acre – A unit of land area equal to 4,840 square yards, or 0.045 hectares.