Designer : URS 



4th and Vine Building 

 Seattle, Washington 



Designer-Fabricator: Bellingham Marine Industries 

 Bellingham, Washington 



(3) Perfor mance . No information is available. Tlie breakwater was 

 under coiistructioa in February 1981. 



d. Discussion, Module connections have been a source of concern for many 

 floating breakwaters. The design for the Seraiahmoo connectors provides for 

 restraint, flexibility, adjustments for maintaining a no-slack connection, and 

 also appears to be easily assembled in the field. 



The Semiahmoo site could be a good site for a field measurement program to 

 collect data on breakwater structural, kinematic, and hydraulic responses. 

 The input data would be limited naturally by the shallow-water conditions and 

 probability of storm and high tide coexistence. 



8. Langley, Washington. 



a. I..oc ation. Langley, Washington (Fig. 27), is a small community on the 

 southeast side of Whidbey Island and faces Saratoga Passage. 



b. Site Conditions. The fetch is long, 8 to 12 nautical miles to the 



northwest and about 4 nautical miles to the east-northeast. Wind data spe- 

 cific to the SLte are not available, but the speed-duration curves for Puget 

 Sound (Fig. 28) should be representative for design purposes. 



Tide data, gathered at Tulallp, Washington, include a mean range of 7.6 

 feet and a diurnal range of 11.2 feet. 



c. Breakwater Description. 



(1) Desi gn and Installation . The breakwater is the Goodyear module 

 floating tire type, composed of tire groups banded together with belting and 

 nylon bolts, with Styrofoam added to the tire crowns for extra buoyancy. The 

 northwest-facing section has a planform of 52 by 230 feet; the east-facing 

 section is 65 by 216 feet. Figure 29 is an east-facing view of the installa- 

 tion. The breakwater is anchored by cables fastened to piling. 



Those responsible for the breakwater design and operation are as follows: 



Owner-Operator: Port of Whidbey Island 



Designer: Parametrix, Inc. 



Everett, Washington 



(2) P erformance . The breakwater reduces the short-crested waves sat- 

 isfactorily, but transmits too much energy in the lower frequencies. Connec- 

 tions in the boat slips were overstressed , and boats have not been permitted 

 to use them. The slips were removed for the 1980-81 winter season. The north 

 end of the east breakwater has been sinking, possibly due to the combination 



47 



