Ridge and swale

[3] Freshwater ridge-and-swale ecosystems are globally rare and found only in parts of the Great Lakes of North America.

[4] They were formed as a result of the gradual retreat of beaches due to falling water levels and post-glacial rebound.

[5] The swales and the adjoining lake or river commonly form a single hydrological unit, so that rising or falling lake levels will cause water levels in the swales to rise or fall as well.

The remaining dune-and-swale complexes along the Great Lakes are often home to extremely rare plants and animals, such as the endangered Karner Blue butterfly.

In the Calumet Region, the difficulty of moving equipment through dune-and-swale topography greatly slowed industrial development, but could not stop it after the turn of the 20th century.

An aerial photograph of the meandering course of the Red River in Lafayette and Miller counties, Arkansas. It shows point bars, abandoned meander loops, ox bow lakes, and ridge and swale topography associated with the active course of the river