The prevailing littoral currents and littoral drift of beach sediment through- 

 out the study area are north to south (U.S. Army Engineer District, Detroit, 

 1980). This prevailing drift is reflected in the accretion of beach sediment 

 on the north sides of groins and other shoreline structures, including the 

 harbor's north breakwater, which interrupt the drift (Figs. 2 to 5). An excep- 

 tion to the prevailing north to south drift apparently occurs immediately south 

 of the harbor, where the accretion of beach sediment on the south side of 

 groins and similar structures suggests that an eddy current causes the prevail- 

 ing drift to move from south to north along the shoreline in areas B and C 

 (Figs. 2 to 5) . 



The beach face profile on 1 6 June 1980 represents the condition which 

 existed before the Corps performed its beach nourishment activities. The accre- 

 tion of beach sediment in area A and the apparent erosion of beach sediment in 

 areas B and C (Fig. 3) are consistent with the conclusion (U.S. Army Engineer 

 District, Detroit, 1980) that the installation of the harbor contributed to 

 erosion of the shoreline south of the harbor by interrupting the littoral drift 

 of beach sediment. 



The removal of about 19,000 cubic meters of beach sediment from area A, 

 the deposition of that sediment in area B, and the deposition in area C of 

 about 3 5,000 cubic meters of sediment from a nearby land borrow site by the 

 Corps in October 1980 caused changes in the beach face profile that are 

 reflected in aerial photographs taken on 3 December 1980 (Fig. 4). Among the 

 major changes that occurred were a retreat landward of the beach face in area A 

 and an advance lakeward of the beach face profile in areas B and C (Fig. 4) 

 from the position occupied on 16 June 1980 (Fig. 3). These changes, caused by 

 the nourishment activities, were relatively short-lived in area A, but were 

 more persistent in areas B and C (Fig. 5). On 6 December 1981 (Fig. 5) the 

 beach face in area A occupied a position lakeward of that observed on 16 June 

 1980 (Fig. 3) before the removal of beach sediment occurred there in October 

 1980. In areas B and C, the beach face on 6 December 1981 had retreated land- 

 ward from the position occupied on 3 December 1980, but had not yet returned to 

 that occupied on 1 6 June 1980. The minor lakeward extension of the beach face 

 at the northern end of area B, which occurred between 3 December 1980 and 6 

 December 1981 , is consistent with the hypothesis that an eddy current exists in 

 areas B and C. 



2. Substrate . 



The results of tests to determine if there was significant variation in 

 particle-size distribution at station 1 among all six transects (the station 

 most likely to be affected by beach nourishment) and for stations 1 to 4 com- 

 bined among all six transects indicated that there were no significant (P = 

 0.05) differences in distribution during any of the six sampling periods, 

 either before or after the beach nourishment activities. These results indi- 

 cate that the beach nourishment project did not alter the ccanposition or the 

 relative distribution of various particle sizes within the sediments in the 

 nearshore area near Lexington Harbor. 



3. Water Quality . 



The water temperatures in both years were typical of the location and 

 season and the DO concentrations never approached levels that could be 



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