Morning-Glory Shaft Spillways: A Symposium: Prototype Behavior

According to available records, the first morning-glory shaft spillway was completed in 1896, but the design did not come into general use until the latter part of the 1920's. Since then, approximately thirty spillways of this type have been completed or are under construction (as of 1955). As less than 30 years have elapsed since completion of the first spillway, it has not been until recently that a morning-glory spillway of any size has operated. Thus the spillway designer has been forced to rely entirely on theory and the results of model studies. Unfortunately, model studies do not solve all the problems involved, and therefore an investigation was begun in 1950 to collect information from spillways which have operated; the results of this investigation are presented herein.