49. During Diana's first pass-by on 11 September, tides along the coast 

 were 2 to 3 ft above predicted levels with a maximum surge of 3 ft occurring 

 around 1530 hr. This maximum surge corresponded with the predicted time of 

 low water, so the actual still-water level at this time was only +0.5 ft. The 

 peak water level associated with the first pass-by occurred around 2200 hr on 

 the 11th with a height of +4.6 ft recorded at Carolina Inlet Marina, located 

 directly across the AIWW from Carolina Beach Inlet. 



50. Diana finally made landfall during the morning of 13 September. 

 Recorded tide levels at the Carolina Inlet Marina during the hurricane's land- 

 fall along with predicted tides for Masonboro Inlet are shown in Figure 1 1 . 

 The Masonboro Inlet predicted tides were used as a basis of comparison since 

 predictions are not available for Carolina Inlet Marina, and the phasing and 

 tide range for Masonboro Inlet and the marina are similar. When Diana made 

 landfall, the predicted astronomical tide was falling and stood at a level of 

 approximately -0.4 ft when the peak surge of 5.5 ft occurred around 0200 hr. 

 Thus, the maximum still-water level recorded at the marina was +5.1 ft. Maxi- 

 mum tides along the open coast were probably similar to this but could have 

 been slightly higher. 



51. Following the passage of Hurricane Diana, beach profile surveys of 

 Carolina Beach were made to determine the changes in the shoreline caused by 

 the storm. These surveys were made between 24 and 28 September and covered 

 the profile lying above the -4 ft plane. The prestorm survey for Carolina 

 Beach was made 4 months earlier in May; therefore, the effects of Diana had to 

 be estimated by subtracting the changes that normally would have occurred dur- 

 ing the 4-month interval from the changes that were actually measured. Normal 

 changes during the 4-month period were based on the average monthly rate of 

 change measured between June 1983 and May 1984. A typical example of the pro- 

 file surveys for June 1983, May 1984, and September 1984 measured at sta 40+00 

 is given in Figure 12. 



52. Between sta 0+00 and 100+00, the volume of material on the profile 

 above the -4 ft plane decreased by 222,900 cu yd between May and September 

 1984. Of this amount, approximately 23,600 cu yd would normally have been 

 lost. Thus, the volume change above the -4 ft plane apparently caused by 

 Diana was 199,200 cu yd. This volume change above the -4 ft depth is equiva- 

 lent to a 45-ft average retreat of the entire foreshore from +8 to -4 ft . 



53. Although poststorm surveys of the offshore section of the profiles 



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