Usufructuary right is a term mostly used in civil law to describe the right of a person to use and enjoy a property that legally belongs to someone else.
Technically, a usufrust refers to the right, while the usufructuary refers to the person.
Usufructuary is a combination of the two words usus and fructus. Both of which have legal connotations in terms of property.
The most common example of usufructuary right is land situated along rivers or streams. Even though the water channel would be owned by the public, al landowners of land adjacent to the stream would have the rights to use the natural resource.
This is related to how easements functions in real estate.
The types of restrictions on the use of the water would depend from place to place.
For example, it would be really pushing the boundaries of the patients of the neighbors and the government decides to build a dam on the river.
It would be an abuse of usufructuary rights.