Table 39 



Indiana Harbor Breakwaters 



Indiana Harbor, Indiana 



Date(s) Construction and Rehabilitation History 



1922 Construction of a 1 , 120-f t-long north breakwater (Figure 102, Sec- 

 tion A) was completed. The breakwater was built of rubble-mound con- 

 struction. It had a crest el of +6 ft Iwd and side slopes of IV:1.5H 

 (Figure 103, Section A). Armor stone sizes along the crest were 

 7 tons (minimum) , and armor stone along the slope (beneath the water 

 surface) ranged from 1 to 7 tons with an average weight of 3 tons. 



1926 Construction of a 201-f t-long east breakwater (Figure 102, Section B) 

 was completed. The breakwater was a stone-filled concrete structure 

 (Figure 103, Section B) built on a stone base. It had a crest el of 

 +6.1 ft Iwd and a width of 8.3 ft. 



1935 A 2, 324-f t-long lakeward rubble-mound extension of the each break- 

 water was completed (Figure 103, Section C) . It had a crest el of 

 +9.0 ft Iwd, a crest width of 10 ft, and 1-V:1.5-H slide slopes. 

 Armor stones along the crest ranged from 7 to 20 tons, and armor 

 along the slope (beneath the water surface) ranged from 2 to 7 tons 

 (Figure 103, Section C) . 



1951- A series of model tests was conducted (Hudson and Housley 1959) to 

 1957 determine the extent of reflected waves in the navigation channel and 

 remedial measures required to alleviate the problems. 



1986 Maintenance costs have been low throughout the lifetime of the break- 

 waters, and the structures are presently in good condition. 



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