the launching and haul -out periods for the marina by 2 to 3 weeks in 

 the spring and the fall. The breakwater is in operation from April to 

 December and is swung up against the shoreline when not in use. A fixed 

 rubble-mound breakwater is also located at the site. 



Design Source: The builder utilized design literature from the University of 

 New Hampshire and the University of Rhode Island. 



Construction: This FTB is 45.7 m (150.0 ft) in length and 6.4 m (21.0 ft) in 

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

 polyethylene blocks inserted in some of the tires. Rubber conveyor 

 belting fastened with nylon bolts is used to couple the tires. 



Site: 



LITTLE BAY 



Stone 

 Breakwater 



I I I I I 



IN 



Installation: The breakwater is fastened at its southern tip to the fixed 

 stone breakwater, elsewhere it is anchored in place. Seven anchoring 

 points are located around the perimeter of the breakwater. The anchors 

 are 1,589-kg (3,500 lb) stone blocks. Mooring lines are of nylon/chain. 



Special Equipment: Orange traffic cones are situated atop the FTB to warn 

 boaters of its presence. 



Field Experience 



Operation: Numerous problems have been encountered in the operation of this 

 breakwater. Litter entrapment is cited as an extreme problem. Fouling 

 growth and inadequate buoyancy are regarded as major problems. To improve 

 flotation which originally relied solely on trapped air, the operator 

 later inserted polyethylene blocks into the tires. Because this repair 

 was done while the FTB was in the water, it was a very difficult task with 

 few blocks actually installed and little improvement made. The operator 

 acknowledges the inadequacy of the present flotation system and notes that 

 a much better one is needed. Anchoring system and mooring-line failures 

 are considered moderate problems. On several instances, the anchors have 

 dragged under strong wave and current action. Structural failure is cited 

 as a moderate problem and instability as a minor one. Coupling failure is 

 also considered a minor problem. Under typical storm conditions with 



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