(8) Does the structure serve functions other than wave attenua- 

 tion? 



(9) What changes in any step from design to operation would be 

 done differently now? 



(10) Has the structure served its intended purpose? 



This report provides an evaluation of 11 floating breakwater installations 

 located in the Pacific Northwest — the thrust of the evaluation being the ques- 

 tions listed above. The results of each site evaluation are presented, and 

 a list of conclusions summarizes the overall field performance of floating 

 breakwaters. 



II. FLOATING BREAKWATER SITES 



1. Ketchikan, Alaska. 



a. Locat ion. The Bar Point Harbor breakwater is located on the north 

 side of Tongass Narrows, a fjordlike waterway, at Ketchikan, Alaska (Figs. 1 

 and 2) . There are 390 moorage spaces planned for both pleasure and fishing 

 craft. Most of the boating activity occurs in the period 15 June to 1 Novem- 

 ber, which spans the seasons for tourism, pleasure craft, and fishing. 



b. Site Conditions. Tue fetch toward the southeast is about 8 miles, 

 about a half-mile across the waterway and practically unlimited toward the 

 northwest. Structures along the shoreline shield the breakwater along the 

 southeast-northwest line. The wind waves travel nearly parallel to the break- 

 water, and sustained windspeeds of 45 to 50 miles per hour with gusts to 70 

 miles per hour are to be expected most winters. 



Tide data are as follows: 



Highest (estimated): 19.5 feet 



Mean higher high water (MHHW) : 15.4 feet 



Mean: 8.0 feet 



Mean lower low water (MLLW): 0.0 foot 



Lowest (estimated): -5.0 feet 



Tidal currents are from south to north on both flood and ebb, with maximum 

 about 6 knots according to harbormaster; National Oceanic and Atmospheric 

 Administration (NCAA) tidal current data report only 1.2 knots. Bottom ele- 

 vations are as follows: 



Along inner row of anchors -20 to -60 feet 



Along breakwater: -50 to -70 feet 



Along outer cow of nachors: -100 to -110 feet 



