Maintenance: No routine maintenance was scheduled. 



Severe Storm Effects: In September 1979, Hurricane David passed over the 

 project area. Winds reaching 145 km/hr (78 knots) were sustained for 

 nearly 2 hours. Seas were from 0.6 m (2.0 ft) to 0.8 m (2.5 ft) high 

 Under these conditions, the anchoring system eventually failed and the 

 tire mat was dragged ashore. 



Cost: The original construction cost was $12,500 divided as follows: $3,000 



for materials, $6,000 for labor, $1,000 for legal fees and permits, $1,500 

 for planning and engineering, and $1,000 for installation. Rebuilding the 

 FTB in 1980 was an additional $10,000. These figures translate to an 

 overall cost of $23.13/m 2 ($2.15/ft 2 ) for the latest design. Disposing of 

 the sunken structure was $3,000. 



Benefits: The operator rated the structure as having a strongly beneficial 

 effect on sportfishing and bird habitation. In its primary role as a 

 shoreline protection device, the FTB was considered as having a positive 

 effect on both sediment movement and shoreline erosion. It is interesting 

 to note that its length to distance offshore ratio was 1:0.36, indicating 

 that its influence on littoral transport should have been very strong. 

 Finally, the operator regarded the breakwater as having a negative effect 

 on waterfront appearance. He rated the FTB as providing high performance 

 in suppressing waves and meeting design goals, and providing moderate 

 performance in satisfying his needs. Overall performance was rated 

 moderate. 



Fouling Characteristics: A variety of marine life inhabited the structure 



including seaweed, barnacles, oysters, crabs, seagulls, terns, and other 

 birds. 



Project Analysis: The primary fault with this project was the use of outdated 

 design literature. Several years before this project began, it was known 

 that polypropylene rope and steel cable were poor couplers. Likewise, it 

 was known that inserted polyethylene blocks seldom held fast and usually 

 provided insufficient buoyancy to balance heavy fouling growth. The 

 eventual sinking of the structure testifies to this--that both 

 accumulated sand and extreme fouling growth overcame the flotation system. 

 More poured foam should have been used, in addition to the structure being 

 placed farther out from shore. Based on the case history of the Santa 

 Rosa Sound FTB, it would appear probable that the breakwater could still 

 protect the shoreline in somewhat deeper water where sand accumulation 

 would not have been so severe. Finally, it should be noted that the lack 

 of regular maintenance precluded any chance of relieving the structure of 

 its problems and signaled the unfortunate demise of the project. 



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