Standard criteria for wind waves and swell in deep draft harbors, such as Kahului 

 Harbor, are not so well established. However, the criteria for shallow draft 

 harbors can provide a useful basis for comparing alternative plans at Kahului 

 Harbor. 



Another, perhaps more valuable, criterion for evaluating proposed new pier 

 areas is to conduct comparisons with existing piers. Many years of practical 

 experience at Piers 1 and 2 can then be approximately transferred to new plans. 



Wave heights for assessing the USACE criteria were computed by combining 

 the time-history of array gage parameters over the time period November 1993 

 through September 1994 with numerical model results to create a time-history of 

 wave heights at each harbor basin. For each array record, the corresponding 

 wave height at a harbor basin is 



(31) 



= (A ), x (H) 



where 



(HJharbor = significant wave height at a harbor basin 



(^amp)eff = spectral amplification factor interpolated between values for 



periods and directions in Table 15 to represent T p and 6 m at the 

 array 



(HJarrw, = significant wave height at the array 



The 1 1 -month time-history of (HJ harbor at each basin was sorted into 

 descending order and the value of H s which was exceeded 10 percent of the time 

 was identified. The H s value exceeded 1 percent of the time was also identified. 

 The H s with 1 percent exceedance relates to a more demanding operational 

 condition, which may be more applicable to large commercial vessels. 



Significant wave heights exceeded 10 percent of the time are less than 1 ft at 

 all existing and most proposed pier areas (Figure 50). The existing harbor is 

 included in each panel of the figure to give a common reference. Existing 

 Piers 1-3 extend approximately between Basins 3-9. Basin 3, which is centered 

 on the proposed extension of Pier 1, has higher wave conditions than any basins 

 along existing piers. Basin 2, the location of a possible future extension of 

 Pier 1, has wave heights approximately twice as high as the main existing Pier 1 

 (Basins 4 and 5). Wave heights at the exposed end of Pier 2 (Basin 10) also 

 approach this level. The significant wave height exceeded 10 percent of the time 

 computed directly from Pier 2 wave gage results is 0.39 ft, which compares well 

 with corresponding numerical model results at Basin 8 in the existing harbor and 

 helps to validate the model wave heights (Table 19). 



Chapter 5 Harbor Response to Wind Waves and Swell 73 



