Technical Abstract: Provision must be made in the design of almost every dam to permit the safe discharge of water downstream. The function of the spillway is to safely convey this discharge past the dam without unacceptable damage. The high velocities and large levels of energy involved in flow over spillways make their design of considerable importance. The design and capacity of spillways play an important role in the layout and economics of every dam project. Spillways are selected for a specific dam and reservoir on the basis of discharge requirements, topography, geology, dam safety, and project economics. This manuscript describes the types, components, and design considerations of open channel spillways.