Flood Control and Wetland Restoration: Meeting Environmental and Drainage Requirements for Multi-Objective Channels

Drainage channels in California have progressed from trapezoidal channels to multi-terraced corridors, primarily as a result of Federal and State wetland and other environmental requirements. The environmental benefits of these more complex channels are significantly greater than those that would have been present with the standard projects that would have been built at these sites and they have also generally provided the drainage benefits predicted. However, costs for two channels assessed in this analysis were much higher than trapezoidal channel projects originally proposed. Essentially, where the sponsor is willing to incur the higher capital costs and has an appropriate design which considers the relevant factors, multi-objective channels can meet all appropriate criteria and will assist the sponsor with permitting and other works.