Operational Condition Indices for Coastal Hydraulic Structures with Discharge Capabilities

Operations of multipurpose hydraulic structures in coastal regions and inland are severely impacted during high water levels, whether accompanied by local precipitation extremes or not. The operational and discharge capabilities of the coastal structures are sometimes adversely affected by high upstream stages and downstream sea levels influencing the tailwater conditions. Despite numerous improvements in assessing canal structures concerning structural safety or hydraulic efficiency, operators have limited tools for decision-making and assessment during severe events. This study, therefore, holds significant importance as it evaluates the associations between extreme (headwater and tailwater) stages and precipitation data sets in a dependency analysis. Furthermore, it proposes and develops multiple operational condition indices to assess the operative capabilities of the structures. The practical implications of these indices are significant, as they can help evaluate the extreme stage levels based on any threshold stage level of interest, such as canal bank elevations, bypass elevation, or top-of-high operating levels. The methodology was applied to nine coastal hydraulic structures in southern Florida. Results point to the advantages of index-based assessments that can lead to improved coastal and inland hydraulic structure operations under extreme hydrometeorological conditions.