Table 9 



Port Allen Breakwater 



Port Allen Harbor, Kauai, Hawaii 



Date(s) Construction and Rehabilitation History 



1935 The 1 ,200-ft-long structure was completed as an extension to a 

 privately constructed breakwater (Figure 21). 



1982 Until damaged by Hurricane Iwa of November 23, the old 8-ton 



keyed-and-fitted armor stone structure had no repair history. The 

 breakwater light at the seaward end had been damaged and repaired 

 several times (Coast Guard cost) prior to its present destruction. 

 The estimated 20-ft breaking waves at the structure first dis- 

 lodged the stones on the inboard crest which eventually resulted 

 in the total destruction of the outer 130 ft of the breakwater. 

 Overtopping waves also displaced crest stone and exposed under- 

 layer stone on a 150-ft length at the extreme root of the struc- 

 ture. Minor damage also was sustained along the inboard slope. 



1984 The head was rebuilt, and the minor damage on the inboard slope 



was repaired at a cost of $178,000. The breakwater was shortened 

 to a total length of 1,126 ft. The outer 74 ft was abandoned. 

 The repair was accomplished by resetting stone remaining on the 

 structure and by retrieving stone from the harbor and replacing it 

 on the structure using the old keyed-and-fitted construction 

 (Figure 22). The crown elevation on the last 80 ft of structure 

 was increased to +13.0-ft mllw. This was done to improve the 

 stability of the inboard slope by decreasing wave overtopping. 

 The root of the breakwater was not repaired. 



38 



