Table 1 



Crescent City Breakwater 



Crescent City Harbor, California 



Date(s) Construction and Rehabilitation History 



1920- The initial work at the project (Figure 3) provided for a 3,000-ft- 

 1926 long rubble-mound breakwater, 6 to 11 ft above mean lower low water 

 (mllw) with a 20-ft crest width. The first 2,245-ft length of 

 breakwater was completed in 1926. Ten- ton armor stones were used 

 for slope protection (Figure 4). 



1928- A 14-ft-wide concrete cap was added to the original 2,245 ft of 



1930 structure raising the crest elevation to 14 ft mllw. 



1931 An additional 755 ft of breakwater construction was completed re- 

 sulting in a 3,000-ft-long structure. 



1939 Construction of a rubble-mound sand barrier connecting Whaler 



Island to the shore (Figure 3) was completed to prevent shoaling. 

 The barrier structure was 17 ft wide at its crest with an ele- 

 vation* of +10 ft mllw (Figure 4). An armor layer of 4- to 6-ton 

 stones protected the ocean side of the sand barrier. 



1946 Construction of a 1 ,200-ft-long inner breakwater was completed to 

 provide protection to a small-craft basin. The inner breakwater 

 extended from Whaler Island northwest (Figure 3). The crest el of 

 the structure was +18 ft mllw (Figure 4) and 10- to 12-ton armor 

 stones were utilized during construction. 



1948 A 1 ,000-ft-long extension of the original (outer) breakwater ex- 

 tending toward Round Rock (Figure 3) was completed. Ten- to 12-ton 

 armor stones were used. 



1948- During storms of 1948 and 1949, the 1 ,000-ft-long extension of the 



1949 outer structure suffered considerable damage. 



1950 The crest el of the entire outer breakwater, with the exception of 

 a 300-ft segment (sta 12+50 to 15+50), was raised to +20 ft mllw 

 with a 22-ft-wide concrete cap to prevent overtopping. 



1950- Winter storm seasons resulted in further damage to the outer break- 



1951 water. Damages consisted of displacement of the concrete cap and 

 armor stones down to about 0.0 mllw in all of the extension located 

 seaward of sta 37+00. 



1952 A modification was authorized which provided for a 1 ,000-ft-long 

 extension of the outer breakwater on a bearing of S80° E (Figure 3) 

 and for abandonment of the existing structure seaward of sta 36+70. 



(Continued) 



All elevations (el) cited herein are in feet referenced to National 

 Geodetic Vertical Datum (NGVD) of 1929. 



11 



