waves 0.8 m (2.5 ft) in height and 6.1 m (20.0 ft) in estimated length, 

 the transmission coefficient is 0.40. 



Maintenance: Scheduled maintenance includes winter storage of the FTB and 

 occasionally cleaning the structure of fouling growth, an undertaking 

 which the operator notes is very difficult. 



Benefits: The operator rated the breakwater as having a positive effect on 

 preventing shoreline erosion and on increasing boaters' comfort. He 

 regarded the FTB as having a negative effect on waterfront appearance. 

 The operator rated the breakwater as providing excellent performance in 

 suppressing waves and moderate performance in meeting design goals and 

 satisfying his needs. Overall performance was rated moderate. 



Fouling Characteristics: A variety of marine life inhabits the structure 

 including mussels, crabs, seagulls, and muskrats. 



Project Analysis: The operator's analysis of this project appears exact. This 

 FTB is a good wave suppressor; otherwise, it is providing but moderate 

 performance. Inadequate buoyancy is the key problem. Although poured 

 polyurethane foam is the best flotation system presently available, this 

 was not the case in 1975. Anchoring system failure is also understandable 

 considering the extreme tidal currents encountered at the site. Perhaps 

 mushroom anchors should have been used instead of stone blocks, so that 

 some additional resistance is met when the structure starts to shift. 

 Finally, the specific purpose should be noted that was originally as- 

 signed this FTB--to extend the launching and haul-out periods of the 

 marina during poor early spring and late fall weather. In this capacity, 

 the breakwater met design goals perfectly. 



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