became larger in April and remained through August. The trough continued to 
shoal through the summer and became more symmetric about the pier axis. 
During this time, the scour hole reached a minimum depth for the year of 
7-1/2 m. Dramatic changes occurred in response to the October storms. The 
high waves and strong currents scoured out the trough, the scour hole depth 
increased to 8-1/2 m, and the fillet at the landward end of the pier was 
eroded away. Only minimal changes occurred during the remainder of the year. 
Bathymetric surveys 
119. Contour diagrams created from the data obtained during the bathy- 
metric surveys are presented in Appendix C; characteristics of the bathymetric 
conditions are discussed below. Birkemeier (1984) provides a detailed discus- 
sion of the nearshore profile changes. 
120. Figure 40 shows the location of the profile lines surveyed away 
from the pier during the monthly bathymetric surveys. 
121. The bathymetric survey on 5 January (Figure 41) shows a trough 
under the pier extending 50 m north and 100 m south with a deeper scour hole 
dominating the seaward 180 m. A wide but fairly stationary storm bar (250 to 
400 m) traversed the survey area interrupted only by the trough under the 
pier. In addition, the nearshore was dominated by a smaller but very mobile 
bar and trough system. 
122. Little change is visible on the 9 February survey (Figure C1). 
The hole at the end of the pier (180 m) had filled in slightly and diminished 
in size. A small amount of shoaling (200 m) was also visible 350 m south of 
the pier. 
123. Very little activity was observed in the 18 March survey (Fig- 
ure C2). Some shoaling of the storm trough (250 m) was visible 150 to 400 m 
north of the pier, and a minor amount of deposition in the trough under the 
pier had taken place. 
124. By 21 April (Figure C3), the scour hole at the end of the pier 
(180 m) had been substantially reduced in area, though the depth remained con- 
stant. The storm bar and trough (200 to 400 m) remained stable with only 
minor changes visible on the nearshore bar (125 m), except under the pier 
where a pronounced 25-m seaward migration of the bar crest had produced a 
prominent seaward bulge in the -1 m contour line. 
125. The next survey on 2 June (Figure C4) showed the nearshore bar 
(175 m) had been replaced by a fairly featureless slope. The storm trough 
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