displaced along the toe, but this movement was considered acceptable. The 

 rock buttress sloughed off to a depth of approximately -5 ft mllw; however, 

 dolosse in the seaward transition area remained stable throughout Hydro- 

 graph A. Photos 202-204 show the structure after testing with Hydrograph A. 

 Testing was then continued using Hydrograph B without rebuilding the struc- 

 ture. The structure remained stable throughout the second hydrograph. 

 Photos 205-207 show the structure after cumulative testing of Hydrograph A 

 and B. Plan 26 was rebuilt and again subjected to Hydrograph A. A total 

 of 409 42-ton dolosse and 152 25- ton armor stone were placed. The structure 

 survived the storm up to the +10 mllw still water level. Damage initiated 

 at the end of the trench for this water level and progressed shoreward as the 

 storm continued; a total of 10 dolosse were displaced. Photos 208-210 show 

 the structure after testing. Although the damaged area eventually appeared 

 to stabilize, it was felt worthwhile to repeat testing of Plan 26 with Hydro- 

 graph A again. A total of 415 42-ton dolosse and 154 25-ton armor stone 

 were placed during rebuilding. Plan 26 performed satisfactorily for this 

 repeat test. Photos 211-213 show the results. Based on these test results, 

 -5 ft mllw is the minimum allowable depth at which the trench should end 

 and Plan 26 appears to be a viable option for stability from wave direc- 

 tion 1 . 



57. Plan 27 (Plate 29 and Photos 214-216) was constructed with a berm 

 of 25-ton armor stone placed offshore of the structure in an attempt to trip 

 the wave and dissipate energy before it reached the seaward transition area. 

 The berm was built after the dolosse were placed and had an average elevation 

 of approximately -14 ft, which stayed about constant shoreward to where it 

 transitioned into the existing breakwater material or dolosse. The berm tran- 

 sitioned from the -14 ft elevation to the sea floor over a distance of about 

 30 ft. Plate 29 shows a plan view of the stone placement. The rehabilitation 

 dolosse were placed in the same geometry as for Plan 26, but no trenching or 

 buttressing was used. A total of 410 42-ton rehabilitation dolosse and 354 

 25-ton stone were used. Plan 27 was subjected to the abbreviated hydrograph. 

 The dolosse in the seaward transition area sustained extensive damage. 

 Photos 217-219 show the structure after testing. The stone berm constructed 

 in Plan 27 was not nearly large enough to dissipate the incoming wave energy, 

 and it was surmised that it would take at least two to three times more volume 

 of stone selectively placed in order for wave attenuation to occur. Based on 



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