Table 65 



Alpena Harbor Breakwater 



Alpena Harbor, Michigan 



Construction and Rehabilitation History 



Date(s) 



1939 A 750-ft-long rubble-mound breakwater (Figure 178) was constructed 

 from the shore extending parallel to the entrance channel. 



1965 The project was modified, which entailed removal of the existing 

 breakwater and construction of a new 550-ft-long offshore rubble 

 breakwater. The new structure would include an 8-ft crest width, 

 4-ton cover stone, a crest el of +8 ft Iwd, and 1-V:1.5-H side slopes 

 on the harbor side with 1-V:1.75-H side slopes on the lakeside 

 (Figure 178). 



1969 The 1965 modification to the project was reclassified into an in- 

 active status based on an unfavorable benefit-to-cost ratio. 



1986 The existing breakwater has never undergone maintenance during its 

 lifetime and is considered presently to be in good condition. 



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(NOT CONSTRUCTED) 



Figure 178. Alpena Harbor, Michigan 



276 



