Session B.3: Coastal Developments

I was surprised that the design standard for the marina berth was 50% at 0.7m for a 1 in 50 year return period storm. This is considerably higher than the design standard used in UK and Ireland. Was the design standard 50% of the berths could have wave heights in excess of 0.7m?

The design requirement was that for 50% of the moorings the H_s would not exceed 0.7m. So indeed for the other 50% of the moorings an H_s larger than 0,7m was allowed. However the design of the breakwaters was made such that only for 4.4% of the moorings the wave height of 0.7m was exceeded. The maximum H_s was 0.8m. This was for a particular wind direction. For the other wind directions the percentage of exceedance was varying between 0 and 0.4% with a maximum H_s of 0.73m.