front. The excursion loss due to sorting was determined in the same 

 manner from estimates on the volume of beach fill lost due to sorting or 

 from volumetric loss calculations based on the critical ratios of the 

 beach-fill material. Note that the initial fill distance, the excursion 

 loss (due to sorting), and the net fill excursion are only comparison 

 estimates and should not be considered as absolute values. Figure 8 

 shows the spatial distribution of the beach-fill excursions along the 

 study area, with an obvious concentration of fill activity in front of 

 the townships of Wright svi lie Beach and Carolina Beach. Areas of 

 reported net beach fill are shown to extend in some places to 

 approximately 100 meters (300 feet). Because these values only reflect 

 the fill excursion remaining after the initial loss period and do not 

 consider the fill loss due to storm-induced or long-term (annual) 

 erosion rates, they are slightly misleading. Most fills were placed 

 after the previous fill had been severely eroded away. 



Table 5 presents all historical events influencing beach volumes 

 since 1965, with a brief description of each event. Storms were 

 included in this table only if noted beach erosion occurred, if asso- 

 ciated storm surge was noted, or if the windspeeds were in excess of 

 80 kilometers per hour (50 miles per hour). A complete list of all 

 storms during the study period is available in supplemental data 

 Volume I, Section B. 



3. Excursion Distance Analysis. 



Selected beach profiles from all stations were plotted at a small 

 scale and visually checked for accuracy and acceptability of data 

 points. Larger scale profiles were then drawn to compare sequential 

 outlines. Areas of erosion from one sequential profile to the next were 

 highlighted by a dot-screen pattern. Typical short and long beach 

 profile plots are shown in Figures 9 and 10. All of the larger scale 

 plots of the short and long beach profiles are contained within sup- 

 plemental data Volumes II to VIII. 



A common base line was established for each sequential profile and 

 the horizontal distance from that base line to the location of the MHW, 

 MSL, MLW, -1.83 meters (-6 feet), -3.66 meters (-12 feet), and 

 -5.49 meters (•'-18 feet) contours were calculated. These distances were 

 plotted against time of measurement, and the relative distance between 

 the first and subsequent distances represents the excursion distance 

 through time for each contour. 



A sample plot from each beach is shown in Figures 11 to 15. A 

 linear regression ("least squares") line which mathematically "best 

 fits" all data points is drawn on these plots. One straight line is not 

 representative of the average excursion rates between the years 1965 and 

 1975, especially for Wrightsville and Carolina Beaches. 



When few data points exist, the scatter due to seasonal fluctua- 

 tions, prior storm erosion, etc., can totally mask the longer term or 



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