wale— A strake, rib, ridge, or raised reinforcing strip along any structure. A horizontal 

 stringer along a sheet-pile bulkhead to which tie rods are attached or against which king 

 piles bear. 



water exchange— Cyclic replacement from outside sources of water in a basin. This may 

 occur as a result of tidal action, river currents, forced circulation, or other means. 



wave attenuation— Reduction of wave height or ampUtude for any reason as the wave is 

 propagated from one area to another. 



wave breaker— A device that absorbs a large amount of wave energy with respect to the 

 amount it reflects or transmits. 



wave convergence— (1) In refraction phenomena, the decreasing of the distance between 

 orthogonals. Denotes an area of increasing wave height and energy concentration. (2) In 

 wind setup phenomena, the increase in setup observed over that which would occur in an 

 equivalent rectangular basin of uniform depth, caused by changes in planform or depth; 

 also the decrease in basin width or depth causing such increase. 



wave energy— The theoretical capacity of a wave to do work. 



wave hindcasts— The calculation from historic synoptic wind charts of the characteristics of 

 waves that probably occurred at some past time. 



wave period— The time for a wave crest to traverse a distance equal to one wavelength. The 

 time for two successive wave crests to pass a fixed point. 



wave propagation— Transmission of waves through water. 



wave refraction— (1) The process by which the direction of a wave moving in shallow water 

 at an angle to the contours is changed. The part of the wave advancing in shallower water 

 moves more slowly than that part still advancing in deeper water, causing the wave crest 

 to bend toward ahnement with the underwater contours. (2) The bending of wave crests 

 by currents. 



wave steepness— The ratio of the wave height to the wavelength. 



weep hole— A drainage or pressure reUef opening in an otherwise watertight structure. 



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