The effect of the pier on shore-parallel contours occurs as far as 300 m away, and 

 the shoreline may be affected up to 350 m from the pier (Miller, Birkemeier, and 

 DeWall 1983). 



Approximately once a month, surveys were conducted of an area extend- 

 ing 600 m north and south of the pier and approximately 950 m offshore. These 

 surveys were conducted to document the temporal and spatial variability in 

 bathymetry. Contoiu' maps resulting firom these surveys, along with plots of 

 change in elevation between surveys, are given in Appendix A. 



All surveys used the Coastal Research Amphibious Buggy, a 10.7-m-tall 

 amphibious tripod described by Birkemeier and Mason (1984), in combination 

 with a Geodimeter 140-T self-tracking, electronic theodolite, distance meter. 

 Profile locations are shown in each figure in Appendix A. Monthly soundings 

 along both sides of the FRF pier were collected by lowering a weighted measuring 

 tape to the bottom and recording the distance below the pier deck. Soundings were 

 taken midway between the pier pilings to minimize errors caused by scour near the 

 pilings. 



A history of bottom elevations below Gauges 645 and 625 is presented in 

 Figure 23 for pier stations 7+80 (238 m) and 18+60 (567 m), along with 

 intermediate locations, 323 and 433 m. 















Distance 















- 1- 











(m) 





-2- 





^_^— ^^^ 







238 





- 3- 





^^^^ ° 





-&-_ 





E 



-4- 





^^^ 



^^-^ 







O- 



-5- 

















Q 



- 6- 



-7- 



' 







~* & 



323 

 433 



" 







-8- 

 -9- 



^ 









567 











JAN FEB 



MAR APR MAY JUN JUL AUG 

 Month 



SEP 



OCT NOV DEC 





Figure 23. Time-history of bottom elevations at selected locations under the FRF pier 



Chapter 7 Surveys 



47 



