berm

A berm is an artificial earthform in the shape of a linear ridge elevated above the surrounding terrain on both sides. Berms are built with piled material, usually soil, gravel, sand, rock, waste material, or similar matter so as to form a long elevated ridge or barrier and are usually covered with pavement, grass, or landscaping. A berm can be used for water retention, as in a levee or dike, or as a roadbed or railroad bed, and may be built in sections connected by overpass bridges.

The piled mass forms the elevated ridge itself. Pavement, grass, or landscaping can cover the material without changing the underlying earthform.

The ridge can carry a road or railway or act as a barrier for water retention. Sections joined by overpass bridges can form part of the same extended arrangement.