Table 21 



Chetco River 



Brookings, Oregon 



Date(s) Construction and Rehabilitation History 



1957 The Jetties were completed. The north jetty was 850 ft long, and the 

 south jetty was 1,550 ft long. The jetties converged to 325 ft apart 

 at the outer ends. 



1959 Rock pinnacles and abandoned bridge piers were removed. 



1962 The outer 440 ft of the south jetty was repaired and raised to pre- 

 vent movement of sand and drift into the navigation channel. Select 

 class "A" stone was used on the outer 110 ft. The rest of the repair 

 work placed a 5-ft layer of class "A" stone over a core of class "B" 

 stone. Select class "A" stones weighed more than 12 tons, class "A" 

 stone weighed a minimum of 6 tons and averaged 10 tons, and class "B" 

 stone weighed between 1 and 6 tons and averaged 3 tons. 



1968 The north jetty was raised to +16 ft mllw and extended 450 ft. The 

 work required an estimated 61,900 tons of class "A", "B", and "C" 

 stone and 14,800 tons of bedding material. Class "B" stone was 

 placed to raise the inner 800 ft of the jetty to +16 ft mllw. An 

 armor layer of class "A" stone was placed over a core of class "B" 

 and "C" stone on the outer portion of the jetty. The final 50 ft of 

 the jetty was composed entirely of select class "A" stone. Based on 

 a unit weight of 160 pcf , select class "A" stone weighed a minimum of 

 11.6 tons; class "A" stone weighed a minimum of 8.1 tons and averaged 

 9.9 tons, placed in a 10-ft- thick armor layer; and class "B" stone 

 weighed a minimum of 5.2 tons, averaged 6.7 tons, and was placed in a 

 layer with a minimum thickness of 9 ft. The rock was placed by a 

 crane on the jetty. 



1970 A protective dike was constructed to protect the small-boat basin 



about 2,500 ft upriver from the jetties. The dike, 1,781 ft long by 

 18 ft high, was constructed of a gravel embankment covered with a 

 riprap revetment of 12-in. quarry spalls on the river side. 



1977 An extension of the north jetty by 750 ft and the south jetty by 

 1,250 ft was recommended. 



1985 The harbor and jetty cross sections are shown in Figure 52. There 

 have been no reports of repairs or rehabilitation since 1970. 



Ill 



