That portion of the foundation, especially in the sides of a valley, which is in contact with a dam. Also, that portion of a dam which makes contact with and abuts against the foundation at the sides of a valley.
The part of a valley or canyon wall against which a dam is constructed. Right and left abutments are those on respective sides of an observer looking downstream.
That part of the valley side against which the dam is constructed. An artificial abutment is sometimes constructed where there is no suitable natural abutment. Right and left abutments are those on respective sides of an observer when viewed looking downstream. The wall between a spillway or gate structure and the embankment can also be referred to as an abutment. See Illustration 1 and Illustration 2