The basis of the original design module of the MELS program suite was developed by Lucia Cade as a part of her research program for the degree of Master of Engineering Science. Frank Winston, during the course of his Master's research, overhauled the design module, developed the performance module of the program and integrated all components. The MEL design concepts grew out of an original idea proposed by the late Prof. Gordon McKay in Queensland, who suggested that a waterway could theoretically be designed such that the flow was critical along its full length. (Hence the early name "Minimum Energy Culvert") To avoid the real and perceived problems inherent with critical flow, the concept was modified to ensure flow remained sub-critical at the design flow. To make a clear distinction between this and the earlier sytems, the name was changed. Apart from Prof McKay, key contributions by Norm Cottman, Colin Apelt and Lew Isaacs are also acknowledged.