Table 5 



North and South Jetties, Humboldt Bay 



Eureka, California 



SPD, SPN 



Date(s) Construction and Rehabilitation History 



1889-1899 Construction of 4,500-ft north jetty and 5,100-ft south jetty; 

 armor stone. 



1911-1915 Reconstruction of south jetty; armor stone. 



1915-1916 Concrete monolith (1,000 tons) added to seaward end of south 

 jetty. 



1915-1925 Reconstruction of north jetty, armor stone; 1,050-ton concrete 

 monolith added to seaward end. 



1925-1927 Parapet walls and concrete caps added to crests of both jetties 

 and mass concrete poured on channel slopes to stabilize armor 

 stone. 



1930-1958 Rehabilitation of both jetties. Mass concrete poured to fill 



eroded areas on crests; armor stones replaced in areas breached 

 and washed out. Both 100-ton concrete blocks (number not 

 known) and 12-ton tetrahedons (number not known) placed on 

 heads of both jetties during this period. 



1960-1963 Rehabilitation of both jetties. Trunks repaired with 12-ton 



stone; reconstruction of heads using 20-ton concrete blocks to 

 form perimeter of heads and centers filled with mass concrete; 

 100-ton concrete blocks (250 total) placed around seaward tip 

 of south jetty head. 



1971-1972 Rehabilitation of both jetties (model tested, Davidson 1971); 



concrete monoliths reconstructed; 42-ton dolosse placed around 

 seaward quadrant of both jetty heads (4 unreinforced, 

 1,271 steel-reinforced, and 17 steel fiber-reinforced dolosse 

 on north jetty, and 22 unreinforced and 1,423 steel-reinforced 

 dolosse on south jetty); 43-ton dolosse placed on the 

 shoreward-transition sections of both jetty heads (967 and 

 1,090 steel-reinforced dolosse placed on north and south 

 jetties, respectively); two layers of dolosse placed using a 

 concentration of 11 dolosse per 1,000 sq ft of slope. 



1986 Repair of spot damage to both jetties using 42-ton fiber rein- 

 forced dolosse (not model tested) . 



NOTE: Design Storm Conditions. 16-sec, 40-ft breaking waves. 



Maximum Storm Condition Exposure. No recorded data but design condi- 

 tions probable. 



