Construction: This FTB is 198.1 m (650.0 ft) long and 9.1 m (30.0 ft) wide. 

 Flotation relies on air trapped in the tire crowns and is aided by 

 polyethylene blocks inserted in some of the tires. A 3/8-inch- 

 high test chain bolted together is used to couple the tires. 



Site: 



Installation: The breakwater is moored by 45 kg (100 lb) mushroom anchors on 

 its leeward side and 363-kg (800 lb) to 454-kg (1,000 lb) railroad wheels 

 .'.'" on its exposed side. The anchors are spaced 30.5 m (100.0 ft) apart. 

 Mooring lines are of chain-wire and are 18.3 m (60.0 ft) long. 



Special Equipment: Flashing white lights and red pylons are situated atop the 

 structure to warn boaters of its presence. 



Field Experience 



Operation: A host of problems are listed as infrequently occurring, but all 

 are considered minor problems of little consequence. These include 

 instability, corrosion, interference with boating traffic, ice damage, 

 fouling growth, inadequate buoyancy, coupling failure, and litter 

 entrapment. Under typical storm conditions with waves 1.1 m (3.5 ft) in 

 height and 20.9 m (68.5 ft) in estimated length, the transmission 

 coefficient is 0.29. No deterioration in performance has been noted since 

 installation. 



Maintenance: Scheduled maintenance consists of shooting compressed air into 

 the tires before the spring deployment for adequate buoyancy. 



Cost: The total construction cost for this breakwater was $10,000 in 1978. 



This figure translates to a cost of $6.72/m 2 ($0.62/ft 2 ) in 1980 dollars. 



Benefits: The operator felt that the structure had a positive effect on 



sport fishing and a strongly beneficial effect on boaters' comfort. He 

 rated the breakwater as providing excellent performance in suppressing 

 waves, meeting design goals and satisfying his needs. Overall performance 

 was rated excellent with the added comment that without the structure, 

 most of the docks could not be properly utilized or maintained. 



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