Table 28 (Continued) 



Date(s) Construction and Rehabilitation History 



1912, The north jetty was extended 400 ft seaward in each of these years 



1913, (1,200-ft total) at a cost of $4,940, $4,800, and $5,000, respec- 



1914 tively. Extensions were 6.0 ft wide with +7.0-ft mlw pile elevations 

 and +5.5-ft mlw stone elevations. 



1915 Both jetties were repaired by adding or replacing broken and decayed 

 timber or piling, and a preservative was applied to tops of piles. 

 Stone was placed to fill settled sections. The cost of repairs was 

 $6,312. 



1920 The south jetty was extended 700 ft to a total length of 5,800 ft 

 using the same type of construction and geometry as the existing 

 jetty. Both jetties were repaired in the same manner as the 1915 

 repairs. Costs of repairs and the extension were $2,422 and $26,033, 

 respectively. 



1939 The north jetty was extended 3,500 ft seaward at a cost of $129,140, 

 using 1912-1914 construction geometry. 



1944 Tops of piles were coated with tar on the north jetty near the river 

 mouth at a cost of $320. 



1948 The north jetty was repaired beginning 708 ft from the shoreward end 

 and extending 942 ft seaward. The original timber crib section was 

 rehabilitated to a rubble-mound structure (Figure 34). The cost of 

 repairs was $51,493, and 4,870 tons of stone were used. 



1963 A survey of the north jetty indicated there was no visible trace of 

 the shoreward 708 ft. The total length of the existing jetty was 

 5,642 ft. The shoreward, rubble-mound, end had an average height of 

 +6.2 ft mlw. The 1 ,200-ft-long timber crib structure adjacent to the 

 rubble-mound section had deteriorated. Upper crib work was virtually 

 nonexistent, and tops of piles were rotted or broken off. Stone had 

 settled an average of 2.8 ft from design, was displaced, and had 

 spilled out between piles. Piles, tie rods, and wales in the most 

 seaward 3,500 ft appeared to be in good condition. Stone had settled 

 an average of 1.5 ft in this section. 



1964 Minor rehabilitation was done on the north jetty at a cost of 

 $377,848. The 1 ,200-ft-long deteriorated timber crib section was 

 rehabilitated to a rubble-mound structure. The center line of the 

 rubble-mound structure was placed north of the center line of the 

 timber crib jetty to prevent failure of the jetty on the channel side 

 due to lateral forces. The offset was 11.0 ft over a distance of 

 650 ft and 9.0 ft over a distance of 400 ft, shoreward and seaward 

 ends of the section, respectively. Transition sections were on 

 either end of the new structure and between the two offset sections. 

 Crest elevation was +7.0 ft mlw, crown width was 10.0 ft, and side 

 slopes were 1V:1.5H. Twenty-five ton minimum capstone was placed 

 over 1- to 50-lb matstone. A layer of willow matting, compressed in 



(Continued) 



59 



