Table 11 

 Halfmoon Bay Breakwaters 

 Halfmoon Bay, California 



Date(s) Construction and Rehabilitation History 



1961 The CE completed construction of two rubble-mound, shore-connected 

 breakwaters to protect the harbor during severe storms (Figure 16). 

 The west breakwater was 2,620 ft long, and the east breakwater 

 4,420 ft long. The crest of each structure varied from +11 to 

 +13 ft mllw with side slopes of 1V:1.5H and 1V:1.75H (Figure 13). 

 The cost of the project was $4,840,000. 



1961- Storms experienced subsequent to breakwater construction indicated 

 1964 they did not provide adequate protection during periods of heavy 



seas and swell. Between 1 96 1 and 1964, 58 moored vessels were lost 

 or damaged, various marina facilities suffered damages, and two 

 lives were lost during storm conditions. 



1967 A 1 ,050-ft-long extension of the west breakwater in an easterly 



direction (Figure 16) was completed to alleviate undesirable wave 

 conditions in the harbor (Wilson 1965). The breakwater extension 

 was constructed with a crest el varying from +13 to +15 ft mllw. 

 The side slopes on the harbor side of the structure were 1V:1.5H 

 with 1V:1.75H side slopes on the sea side for the first 900 ft. 

 The side slopes on the head varied from 1V:1.5H to 1V:2.25H. The 

 cost of the extension was approximately $1,957,400. 



1986 A condition survey of the navigational facilities presently is 

 under way. 



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