Table 46 



Swinomish Channel 



Washington 



Date(s) Construction and Rehabilitation History 



1892 The project was adopted. 



1893 The north Jetty was constructed. The jetty was extended west from 

 "Hole in the Wall" to Saratoga Passage. The Jetty was of rubble- 

 mound and timber pile construction over brush mattresses with crest 

 elevation of +8 ft mllw, crest width of 4 ft, and side slopes of 

 1:1. The timber piles were placed in a row along both sides of the 

 crest with 6-ft center-to-center spacing. 



1900 The north Jetty was reconstructed. 



1908 The south Jetty, extending west from Goat Island into Saratoga Pass- 

 age, was constructed of pile and rock. The Jetty extended 3,650 ft 

 to deep water with a crest elevation of +8 ft mllw. A 300-ft gap for 

 fish and boat passage was left between Goat Island and the Jetty. 



1938 The Goat-McGlinn Island Jetty was constructed of rubble mound over a 

 30-in. -thick layer of brush mattresses. The crest elevation was 

 +15 ft mllw with a 3-ft crest width and 1:1 side slopes. 



1941 The Goat-McGlinn Island Jetty was reconstructed to a +15 ft mllw 

 crest elevation with 5-ft crest width and 1:1 side slopes using 

 33,185 cu yd of stone. It was then repaired in September with 

 197 cu yd of stone and in October with 210 cu yd of stone. 



1945- The Goat-McGlinn Jetty was rehabilitated with side slopes changed 

 1946 from 1:1 to 1:1.5, using 38,812 tons of rock. 



1962 Navigation hazards at "Hole in the Wall" were removed. 



1963 The Goat-McGlinn Jetty was repaired using 16, 408 tons of rock. 



1973 Major rehabilitation and extension of south Jetty were effected. The 

 Jetty had originally extended to deep water, but sediment deposits 

 had enlarged the shallow shelf, and the Jetty head was 1,000 ft from 

 deep water at this time. The crest elevation of the Jetty was +1 to 

 +2 ft mllw, except for the outer 8OO ft which was below mllw. The 

 Jetty was reconstructed of quarry spall and rock, 4,100 ft long, with 

 crest elevation of +8 ft mllw, crest width of 8.5 ft, and side slopes 

 of 1:1.5. Treated timber piles were placed on 200-ft centers on the 

 Skagit Bay side to mark the structure, which would be submerged at 

 high tide. Two gaps, each 50 ft wide, were left for fish passage, 

 along with the existing 300-ft gap for fish and boat passage. A 

 3-pile dolphin was placed at each end of the Jetty. Construction 

 required 54,310 tons of rock. 



(Continued) 



170 



