Some construction jargon comes from the appearance of wildlife and, after consideration, makes sense, like the term “alligatoring.” While others like “girder” come to life from related words. In this case, I have no frame of reference for the term “berm.”
However, Merriam-Webster gives us the word origin:
French berme, from Dutch berm strip of ground along a dike; akin to Middle English brimme brim | First Known Use: 1704
According to the Construction Dictionary, 9th Edition © 2001 published by the Greater Phoenix, Arizona Chapter #98 of the National Association of Women in Construction alligatoring is defined as follows:
(1) An artificial ridge of earth, generally side slopes of a roadbed and commonly called the shoulder. The space between the toe and slope and excavation made for intercepting ditches or borrow pits. Berms are built to hold water on land that is to be flood irrigated. (2) In dam construction, a horizontal step or bench in the sloping profile of an embankment dam.
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