One of the major goals of the test program was to investigate various 

 methods of connecting (or fendering) the two 140- ton floats. Several different 

 connection methods were tested: rigidly bolting the units together, using 

 three types of flexible connectors, and disconnecting completely (with fender- 

 ing). Both the rigid connection and the fendering (Photograph 22) were suc- 

 cessful. None of the flexible connector designs survived their test period 

 undamaged, although considerable progress was made toward a viable flexible 

 connection design. 



Upon completion of the field test, diver inspections of the anchor lines 

 and the concrete floats were made. No significant damage, wear, or cracking 

 was found on the floats. The galvanized steel anchor lines were visibly cor- 

 roded, and the shackles used to attach the clump weights to the anchor lines 

 were worn; otherwise the anchor line hardware, including the chain, was found 

 to be in excellent condition. 



For nearly a year, the pipe-tire breakwater proved to be remarkably dur- 

 able. Except for minor repairs to the keeper pipes, it withstood the winter 

 storms of 1982 without any maintenance (Photograph 23). But in June 1983, 

 almost a year to the day after the pipe-tire breakwater was installed, the 

 first problem of any consequence developed. After a minor storm, routine in- 

 spection revealed that one of the longitudinal pipes had broken (Photograph 

 24). Further scrutiny revealed that the 45-ft pipe had been fabricated from a 

 40-ft section and a 5-ft section. A poor weld between the two sections had 

 finally failed because of a combination of corrosion and fatigue, allowing the 

 two pipe sections to pull out of the tires. One month later, when a second 

 pipe failed in exactly the same manner, a decision was made to terminate test- 

 ing of the pipe-tire breakwater. The pipe-tire breakwater anchor lines were 

 inspected during the removal process, and no major problems were found in 

 either the nylon anchor lines or the connecting hardware. After the break- 

 water was removed, it was eventually reinstalled at a private marina in 

 southern Puget Sound. Monitoring of the long-term durability of this unit is 

 planned. 



While the Floating Breakwater Prototype Test Program was under way, two 

 projects using floating breakwaters were designed and constructed by NPS. In 

 1983, a 600- ft- long breakwater was constructed for the 800-boat East Bay Marina 

 at Olympia, Washington (Photograph 25). A year later, another floating break- 

 water, 1,600 ft long, was anchored at Friday Harbor, Washington (Photograph 26). 



117 



