Table 49 



Willapa River and Harbor and Naselle River 



Willapa Bay, Washington 



Date(s) Construction and Rehabilitation History 



1916 Willapa River and Harbor project adopted. 



1954 The Willapa River and Harbor project was modified to include the 

 mooring basin and the breakwater at Nahcotta. 



1957 The breakwater design at Nahcotta was modified to conform to requests 

 by local interests. 



1957- The Nahcotta breakwater was constructed. The 1 ,500-ft-long break- 



1958 water was of rubble-mound construction, with the crest at elevation 

 +15 ft rallw, width of 6 ft, and side slopes of 1:1.5. The landward 

 end tied into an existing oystershell mound at the landward end of 

 Nahcotta Wharf. A 2-ft-thick layer of quarry spalls was extended 

 15 ft from the seaward toe on the channel side of the breakwater to 

 protect against toe scour. The breakwater required 43,700 tons of 

 rock to complete. 



1958 The Nahcotta mooring basin and channels were dredged. 



1985 The harbor layout and breakwater cross sections are illustrated in 



Figure 82. There are no reports of needed repairs or rehabilitation 

 for the breakwater. 



177 



