Excellent point! Every year there is a 1 % chance (1  in 100) of occurrence of this event. But, what about a more severe event like what has happened in Florida? In such a case, these flood walls would likely be overtopped. So, in reality, Waikiki is only protected up to a point. What happens with sea level rise? Sure, the walls along the Ala Wai would prevent its water from entering Waikiki, but what prevents water from the ocean side from entering Waikiki? Already storm drains back up during high tides, and we have seen this year king tides pushing wave water into hotel entrances on the beach side.  I don't think that this proposed project and a $300 million expenditure would really help things. Maybe Civil Beat could explore the somewhat larger picture of "protecting" Waikiki overall. Is it even possible? The State is working on some sort of plan or report due at the end of this year which may be our first look at sea level rise impacts.