Encroachment

An illegal intrusion in a highway or navigable river, with or without obstruction. An encroachment upon a street or highway is a fixture, such as a wall or fence, which illegally intrudes into or invades the highway or encloses a portion of it, diminishing its width or area, but without closing it to public travel.

In the law of EASEMENTS, where the owner of an easement alters the dominant tenement so as to impose an additional restriction or burden on the servient tenement, he or she is said to commit an encroachment.