IWRA Proceedings

Urban stream flooding is of increasing frequency largely due to watershed development. Many cities are faced with providing flood protection for higher and more frequent flood flows. Generally, projects have provided improved channels along with levees and facilities to contain flood flows at desired frequency levels. However these proven solutions have been labeled as “structural” and are generally attacked by certain non-technical environmental planning groups which advocate nonstructural or naturalist approaches for flood containment. The hydraulic engineering technology for controlling floods is well known and has long been successfully applied in the USA by the Army Corps of Engineers and other flood control agencies. The benefit/cost ratio of a project has been a standard reference for project approval, but this measure of tangibles seems to be ignored where certain environmental issues come into play. Yet the question remains as to how human life and property can be properly protected at a reasonable cost to the public at large and still satisfy all environmental desires. The aim of this paper is to examine the application of flood control alternatives for the conveyance of floods and to draw some conclusions as to their effects.