SmithGroup engineers perform an underwater breakwater inspection at the Ayai Napa marina in Cyprus.Įven though it may seem obvious to conclude that a particular storm caused a specific problem or failure, the monitoring data will provide the information needed to more accurately determine how the breakwater structure and the marina sustained damage. Rising water levels also impact shoreline erosion and sediment levels along breakwaters and harbor entrances, so it is helpful to monitor how those conditions are changing as well. This monitoring also needs to account for changes in the baseline environmental conditions that the structures are subjected to, such as water level, wave climate, river flows and sediment transport. In addition to identifying immediate need repairs, the initial inspection provides a critical baseline to reassess breakwater performance and stability in the future, especially after major wave/storm events.Įstablishing an ongoing monitoring program is also essential to identify whether a breakwater’s condition and performance are stable, improving or deteriorating over time. The destructive consequences of waves, tides and fluvial action on marina breakwaters can be readily observed through changes in the profile shape of the structures, scouring at the toe, settlement and deterioration of rubble mound breakwaters as stones are displaced or fractured. Determining the current service level and condition of all breakwater structures within a harbor system is essential to identify and prioritize maintenance needs moving forward. The next step is to perform a thorough inspection and conditions assessment both above and below the water line. Even knowing the typical performance assumptions for a comparable breakwater cross-section can be extremely helpful in evaluating how performance is likely to change as water levels rise and storms intensify. While there isn’t always specific documentation available to help a marina owner answer these questions, particularly if a facility is very old, in many cases there are relevant examples of similar breakwaters that were built around the same time using similar specifications and materials. What were the known historic high and low water levels and tidal dynamics that informed the design? How did the design account for extreme wave and storm events and their potential impact on structural stability and overtopping? What storm severities/frequencies were assumed? Most existing breakwaters were designed in response to historic averages known at that time for a particular geographic region. The first step is having a clear understanding of the conditions for which the breakwater structure was designed. Adopting an appropriate strategy to monitor breakwater facilities allows a marina owner/operator to make informed decisions on how to maintain the desired protection and performance level in the most cost-effective manner possible. When water levels pass a certain height, the breakwater will become ineffective and no longer safeguard the vessels and infrastructure it was originally built to protect. Larger storm waves can also accelerate breakwater deterioration and potentially lead to structural failure. As water levels rise, wave overtopping of the breakwater will increase, resulting in agitation in the marina basin that can damage the infrastructure and vessels moored within. This is particularly important for marinas facing sea level rise, along with the more severe storms caused by global warming. Regular monitoring and maintenance are paramount if the performance levels of these breakwaters are to be preserved. Many marinas are protected by rubble mound or sheetpile breakwaters, some of which are approaching the end of their life cycles.
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