Water level was maintained within ±0.002 foot. The concrete bottom 

 elevations varied as much as 0.1 foot in the 6-foot tank and 0.05 foot 

 in the 10-foot tank. The wave period was controlled to within ±0.01 

 second. 



The reflection coefficient was determined by both a manual and an 

 automated method, with the automated method giving values Q.Q3 and 0.04 

 lower than the manual method for the 1.90-second wave. 



Profile surveys were recorded by a point gage with a 1-inch gimbaled 

 foot in place of the point. The survey accuracy was ±0.05 foot in the 

 x-direction [onshore-offshore), ±0.02 foot in the y-direction (longshore) 

 and ±0.02 foot in the z-direction (vertical). The vertical accuracy 

 includes the effect of ripples. Data were reduced by the BEPROF package 

 of programs at CERC. 



Breaker type, position, and, in some experiments, height were deter- 

 mined. Ripple formations were photographed and sand samples collected 

 when the wave tanks were drained. Sand samples were analyzed for size 

 distribution by the RSA, the dry sieve method, and the VA Tube. 



Water temperature was measured twice daily at the surface and the 

 bottom of each tank. Current data were collected in the last six experi- 

 ments by observing the paths taken by small, nearly neutrally buoyant 

 floats. 



46 



