Design Source: The builder utilized design literature from the New York Sea 

 Grant Program. 



Construction: This FTB is 91.4 m (300.0 ft) in length and 1.8 m (6.0 ft) in 



width. Flotation relies solely on air trapped in the tire crowns. Rubber 

 conveyor belting fastened with stainless-steel bolts is used to couple the 

 tires. 



Site: 



ST. LAWRENCE RIVER 



i — r 



15 



Installation: The breakwater is tied to pilings by conveyor belting on its 

 leeward side and anchored on its exposed side. The pilings are spaced 



3.0 m (10.0 ft) apart. The anchors are 227-kg (500 lb) concrete blocks 

 and are spaced 7.6 m (25.0 ft) apart. Anchor lines are of chain and are 



6.1 m (20.0 ft) long. The builder noted that transporting the breakwater 

 from its inland construction site to the water was a very difficult 

 undertaking. 



Special Equipment: Red and green navigational lights and daymarkers are 



installed on the structure as per local Coast Guard requirements. On his 

 own initiative, the builder placed flashing white lights between the 

 colored navigational lights to further deter possible collisions. 



Field Experience 



Operation: Litter entrapment is considered a major problem by the operator. 



Inadequate buoyancy is cited as a moderate problem. Given the opportunity 

 to rebuild, the operator would fill the tires with polyurethane foam to 

 improve flotation. Ice damage and fouling growth are both minor problems. 

 Under typical storm conditions with waves 0.6 m (2.0 ft) in height and 

 7.4 m (24.3 ft) in estimated length, the transmission coefficient is 0.08. 



Maintenance: Scheduled maintenance consists of occasionally lifting the tires 

 to retrap air. 



Severe Storm Effects: During an exceptionally bad storm in April 1979, some 

 of the tires sank and it was necessary to lift them out of the water to 

 capture air and refloat them. Nonetheless, the FTB successfully 



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