Table 51 (Concluded) 



Date(s) Construction and Rehabilitation History 



breakwater (Figure 142, Sections D and E) involved the placement of 

 new core stone over the existing riprap and cover stone on each side 

 of the structure. The cover stone was 8 tons (minimum 10-ton 

 average) with a crest el of +3.0 ft Iwd and side slopes of 1V:1.5H. 



1970- Portions of the north and south breakwaters (Figure 139, Sections A, 

 1971 B, C, and Fl) were repaired. The lakeward portion of the north 



breakwater (Figure 141, Sections A and B) included the placement of 

 new core stone over the existing riprap and 8-ton minimum to 10-ton 

 maximum cover stone with an el of +3.0 ft Iwd on each side of the 

 breakwater and 1-V:1.5-H side slopes. Repairs to Sections C and Fl 

 of the north breakwater and Section Fl of the south breakwater (Fig- 

 ures 141 and 142) included core stone and 8- to 12-ton cover stone on 

 the lakeside of the structures with an el of +3.0 ft Iwd and 

 1-V:1.5-H side slopes. Toe stone on each side of the breakwaters 

 ranged from 10 to 15 tons. 



1974- A hydraulic model investigation was conducted (Crosby and Chatham 

 1975 1975) to determine optimum design features at the breakwater entrance 

 which would allow the passage of larger and deeper draft vessels 

 while still providing wave protection at the existing docking 

 facilities. 



1977- The south pier (Figure 139, Sections L, M, and N) was reconstructed. 



1981 The new pier consisted of a rubble-mound structure with a concrete 



cap which ranged from 9.5 to 11 ft in width (Figure 143, Sections L, 

 M, and N) and had a crest el of +7.0 ft Iwd. The lakeward portion of 

 the pier included 3- to 6-ton cover stone (Sections L and M) , and the 

 remaining portion had 100- to 250-lb cover stone. Side slopes of the 

 pier were 1V:1.75H. A wave absorber was installed adjacent to the 

 north pier (Figure 140) with a slope of 1V:1.5H and an el of +7.0 ft 

 Iwd. Cover stone ranging from 2.5 to 5 tons was utilized. 



1985 Site inspection of the structures indicated that they were generally 

 in fair condition with the breakwater caps in need of maintenance. 

 An aerial view of the Ludington Harbor structures is presented in 

 Figure 144. 



225 



