trap (typically, about 1 m) so that sand scoured from the seaward trap and 

 transported shoreward with the incoming waves would not be collected by the 

 shoreward trap. Waves and currents were not measured during consistency 

 tests. The consistency tests performed on 9 September were made in the south 

 longshore feeder current of a rip current. 

 Rip current measurement 



36. An experiment was performed on 9 September, the final day of data 

 collection, with the objective of measuring the water flow and sand transport 

 in the rip current located just north of the FRF property line. Two traps 

 each were placed in the north and south longshore feeder currents of the rip, 

 and three traps were placed in the throat of the rip. Streamers on traps 

 placed in the strong offshore current flow in the rip throat extended seaward, 

 directly against the incident waves. The experiment showed that the amount of 

 sand entering the rip from alongshore was approximately equal to that leaving 

 seaward in the throat (Kraus and Nakashima 1987). Sampling in the rip current 

 can be seen on the DUCK85 video (Hughes and Kraus 1985). 



Currents 



37. The two current meters were placed at representative locations 

 along a line crossing the surf zone just north of the photopole line. The 

 meters were moved as necessary if the surf zone width changed with the tide. 

 Positions of current meters are listed in Table A3 of Appendix A. The basic 

 processed current speed data are given in Table 3 for nine runs. The run ID 

 number for the current meter records have a "dot extension" which identifies 

 the current meter component (C) as the x- or y-component, and the meter as 

 number 1 or 2 . The x-axis points offshore (positive x-component indicates 

 seaward -directed flow), and the y-axis points north. Current meter 1 was 

 located shoreward of current meter 2. 



38. In Table 3, current speeds are given to the tenth of a centimeter 

 per second to reduce roundoff error in analysis; the meters probably do not 

 measure with that accuracy. The mean current speed, standard deviation, and 

 maximum and minimum current speeds listed in columns three through six, 

 respectively, were calculated for the indicated trap sampling interval. The 

 mean over the trapping interval can be compared to the mean speed for the 



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