b. Plan 2 (Plate 2) included the elements of Plan 1 with a 198-m-long 

 (650-ft-long) seaward extension of the breakwater, resulting in a 1,006- 

 m-long (3,300-ft-long) structure. 



c. Plan 3 (Plate 2) entailed the elements of Plan 1 but the dogleg portion of 

 the breakwater was reoriented slightly to the west and extended by 46 m 

 (150 ft) in length. This resulted in an 853-m-long (2,800-ft-long) struc- 

 ture with a 122-m-wide (400-ft-wide) navigation opening between the 

 breakwater and the causeway dock. 



d. Plan 4 (Plate 3) consisted of the elements of Plan 2 with a slight reorienta- 

 tion of, and a 12.2-m-long (40-ft-long) extension to, the block dogleg 

 breakwater. This resulted in a 1,018-m-long (3,340-ft-long) structure. A 

 107-m-wide (350-ft-wide), 6.7-m-deep (22-ft-deep) entrance channel, and 

 a 6.7-m-deep (22-ft-deep) turning area (adjacent to the docks on the 

 causeway) were installed. From this point the channel transitioned to 

 45.7 m (150 ft) in width and 3.7 m (12 ft) in depth and extended northerly 

 through the sand spit into the Snake River and then easterly into the 

 existing harbor. A 3.7-m-deep (12-ft-deep) deposition basin also was 

 installed between the 3.7-m-deep (12-ft-deep) inner channel and the 

 causeway. 



e. Plan 5 (Plate 3) involved the elements of Plan 4, but the breakwater was 

 reduced in length by 1 10 m (360 ft) and the outer end was reoriented to 

 the west. The total breakwater length was 908 m (2,980 ft) and the 

 navigation opening was 137 m (450 ft) in width between the breakwater 

 and the causeway dock. The existing harbor entrance also was closed. 



/. Plan 6 (Plate 4) entailed the elements of Plan 5 with a 41 . 1-m-long 



(135-fHong) southerly extension of the causeway. The causeway exten- 

 sion was of rubble-mound construction. 



g. Plan 7 (Plate 4) included the elements of Plan 6 with an additional 15.2-m 

 (50-ft) extension of the causeway, resulting in a 56.4-m-long (185-ft-long) 

 structure. 



h. Plan 8 (Plate 4) involved the elements of Plan 7, but the breakwater was 

 reduced by 73 m (240 ft) in length and its head reoriented westerly. The 

 total structure length was 835 m (2,740 ft), and the 137-m-wide (450-ft- 

 wide) navigation opening was maintained between the breakwater and the 

 causeway dock. 



i. Plan 9 (Plate 5) consisted of the installation of a 927-m-long (3,040-ft- 

 long) rubble-mound breakwater. The structure originated approximately 

 579 m (1,900 ft) east of the causeway and extended seaward parallel to 

 the entrance channels before it curved to the southwest. The navigation 

 opening between the breakwater and the outer causeway dock was 137 m 

 (450 ft) in width. The plan also included the dredging described in 

 Plan 4, and the existing harbor entrance was closed. 



Chapter 4 Experiments and Results ' " 



