ABSTRACT
Submerged vanes are an unobtrusive and cost-effective way for river engineers to address many problems associated with river management. The vanes are small flow training structures designed and installed on the river bed to modify the near-bed flow pattern and redistribute flow and sediment transport within the channel cross section. The structures are laid out so they create and maintain a flow and bed topography that is consistent with that of a stable channel creating optimum conditions for managing the river. A relatively new technology, submerged vanes are a low-impact method for restoring river banks, stabilizing or re-meandering river reaches previously modified (straightened) by humans, increasing flood flow capacity, reducing sediment deposits, and for helping maintain or enhance the ecosystem in and around rivers. Following laboratory research and feedback from field installations, guidelines are now available for designs that are effective and sustainable. Several field installations have been in place for a substantial length of time. The experience from these installations is summarized. One such installation is described in detail. In another case, a vane system has been used to re-activate a submerged-screen water intake system that had been inundated with bed sediment to the extent that it could be used only following significant dredging operations. A vane layout was designed in 2011 to intercept and deflect bed sediment around the screen system and create and maintain sediment free approach-flow conditions at the screen system. This design is also described. The results suggest new, promising areas of application for the vane technology.
