Streambank Protection by Submerged Vanes

Abstract

A summary is given of the design, installation and performance of a system of submerged vanes (“Iowa Vanes”) for erosion protection in a bend of East Nishnabotna River, Iowa. The system functions by eliminating, or reducing, the centrifugally induced helical motion of the flow (the root cause of bank undermining). The system was installed during the summer of 1985. Its performance was evaluated with data obtained in surveys in the spring of 1986. The system was found to effectively reduce velocity and scour along the bank without changing the energy slope of the channel. Areas of design improvements were identified. The summary includes a brief description of the theoretical and experimental background for the design.