jetty could be seen seaward of the structure in wave troughs as they 

 passed. Other observations revealed some low areas in the crest and 

 some voids on the sea side of the jetty. Consideration should be 

 given to designing a cap to stabilize the head of the jetty and pre- 

 vent it from unraveling further. In addition, consideration should 

 be given to placing armor stones in the voids of the structure during 

 scheduled maintenance to prevent future major damage, and in areas 

 along the structure crest to bring the jetty back to its design cross 

 section. The structure should be checked after major storm events. 



e. Inspection of the Siuslaw River jetties, Oregon, indicated that some 

 damage had occurred since the previous monitoring in 1993. Voids 

 at two locations on the channel side of the north jetty were observed 

 as well as low areas in the center of the jetty crest. Damage on the 

 head of the south jetty was observed as evidenced by a lack of stone 

 above the water surface and a very steep slope. In addition, two 

 void areas were noted on the shoreward side of the south jetty spur. 

 Consideration should be given to placing armor stones in the voids 

 and damaged areas identified on the jetties and jetty spur during 

 scheduled maintenance to prevent further damage in the event of a 

 major storm. Consideration should also be given to placing armor 

 stones in areas along the structure's crest to bring it back to its de- 

 sign cross section. The structures should be inspected after major 

 storm events. 



/. Inspection of the Umpqua River training jetty, Oregon, indicated it 

 was generally in very good condition. At the shoreward end of the 

 structure it was noted that some stone from the jetty was scattered 

 on the shore. Inspection of the south jetty indicated a breach at its 

 head and a large void on the sea side of the structure just shoreward 

 of the breach. The breach did not extend below the water surface. 

 The trunk of the south jetty was in good condition. Consideration 

 should be given to repairing the breach and void at the head of the 

 south jetty with armor stones during scheduled maintenance to pre- 

 vent further damage and potential failure of the structure in the 

 event of a major storm. The breakwater system then should be in- 

 spected periodically especially after major storms. 



g. Inspection of the Crescent City Harbor breakwater, California, indi- 

 cated that most of the armor unit positions were similar to those of 

 the previous survey of 1993. Only a couple of units had slightly 

 changed positions along the waterline on the sea side of the outer 

 portion of the main stem. Broken armor units were observed, but 

 validated as being broken during the 1993 survey. Overall the struc- 

 ture is in good condition. It should be periodically monitored, and 

 particularly after major storm events. 



h. Inspection of the Spud Point Marina breakwater, California, indi- 

 cated no evidence of misalignment, movement, spalling, or subsi- 

 dence of the structure. Hairline cracks across the breakwater cap 



Chapter 3 Summary and Recommendations 51 



