This technical report presents a method for the preliminary hydraulic design of a step-pool type, nature-like fishway. The method and its companion example, “Nature-Like Fishway at the Obex Mills dam site”, are presented as an instructional exercise illustrating how one may bridge the gap between a conceptual layout and subsequent, more detailed, design phases. This report is intended to supplement the “Federal Interagency Nature-like Fish Passage Guidelines for Atlantic Coast Diadromous Fishes” (unpublished; forthcoming 2015).