fetch— The area in which seas are generated by a wind having a rather constant direction and 

 speed. Sometimes used synonymously with fetch length. 



fetch length— The horizontal distance (in the direction of the wind) over which a wind 

 generates seas or creates a wind setup. 



filter— The underlayer of small rock or gravel that permits proper seepage and dissipation or 

 distribution of water beneath or behind a structure wall or riprapped slope without 

 allowing the earth or other retained material to escape. Plastic cloth may also be used as 

 a filter. 



fines— Grains of silt and clay magnitude that are carried away in suspension by waves and 

 currents. In stonework, any material smaller than the smallest grading classification or 

 sieve size in a given specification. 



finger pier- A comparatively smaller pier structure attached (usually perpendicular) to the 

 headwalk of a multislip pier; usually provided to facilitate access to the berthed craft. 



foot-candle— A uniform measure of light intensity standardized by the Illumination 

 Engineering Society. 



formwork— The structure used to contain and shape poured concrete. 



freeboard-The additional height of a structure above design high water level to prevent 

 overflow. Also, at a given time, the vertical distance between the water level and the top 

 of the structure. On a ship, the distance from the water Une to main deck or gunwale. 



french drain— A continuous run of buried gravel through which water can flow for drainage 

 purposes. 



gabion-A connected system of wicker or metal cages filled with brush or rock and used for 

 slope protection or stabilization. 



gangway— A pedestrian or handcart bridge affording access from shore or a shore-connected 

 fixed pier to a floating structure (sometimes called brow). 



grid (gridiron)-A woven or welded metal mat or framework used for ramps, slope 

 stabUization, or erosion control. 



guide piles-The piles in a floating dock system that resist the horizontal displacement of the 

 system but allow and guide its vertical movement with changes in the level of the water 

 surface. 



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