g. Profile Site 7 . Essentially no loss of sediment occurred during 

 either of the last 2 years; however, there was a considerable loss during 

 1970-71. Although the distance and depth of each permanent longshore bar 

 are slightly greater than the mean, ephemeral bars are typical at this 

 site. The effect of these bars appears to be paramount in protecting the 

 coast from high wave energy. 



h. Profile Site 8 . There was no significant loss of sediment from 

 the profile at this site. A total of 55.5 cubic feet was lost over the 3- 

 year period with only 16.5 cubic feet during the last year. Although an 

 ephemeral bar was present during the August 1972 nearshore survey, such 

 bars were not typical at that site. A twofold explanation is offered for 

 the lack of erosion at this site. The second permanent bar is relatively 

 close to shore and almost 2 feet shallower than the mean. In addition, 

 the profile is located just south of a concrete slab seawall which shelters 

 the profiles from waves coming from the north and serves as a site of sedi- 

 ment accumulation for material transported to the north by waves approach- 

 ing from the south. Unlike the structure at site 4, this protective struc- 

 ture is quite open so that there is a minimal reflection of wave energy. 



i. Profile Site 9 . The loss of almost 200 cubic feet of sediment 

 from this profile during 1972-73 places this location among the most se- 

 'verely eroded during that period. Nearshore profile data collected in 

 August 1972 indicate that the coast at this site should have been well 

 protected. An ephemeral bar was typically present at this site, and the 

 permanent bars were near mean values for depth and distance. Apparently, 

 there was considerable change in the profile during high wave energy per- 

 iods or other factors not apparent from the data caused this erosion. 



j. Profile Site 10 . Erosion at this site was the least (9 cubic feet) 

 during 1972-73 of all sites surveyed. Ephemeral bars were not present 

 and the permanent bars were close to the mean in depth. They were some- 

 what closer to the beach than mean values; however, this is not considered 

 significant in itself. The most effective protection afforded the coast 

 at this site is the tough and resistant clay till which comprises the 

 bluffs. There was essentially no beach throughout the 1972-73 study year; 

 waves were imported directly on the till bluffs with no appreciable effect. 



k. Profile Site 11 . This site is one of the most puzzling of all 

 those monitored. More than 100 cubic feet of sediment was lost from the 

 profile although the August 1972 nearshore survey indicated excellent pro- 

 tection by the longshore bars. An ephemeral bar was present which is com- 

 mon at this site. The depth of the first bar was 1 foot less than the mean; 

 the second bar was 15 feet less. All of this suggests that much of the 

 wave energy should be dissipated before reaching the beach. 



During July 1970, nearshore profiles were surveyed across the same 

 traverse at site 11 as part of another study (Davis and Fox, 1971) . A 

 total of four profiles was surveyed during the study. At that time the 

 first permanent bar was more than 100 feet farther from shore and had a 

 crest 1 foot deeper than in August 1972. The second bar was about the same 



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