support facilities— Installations or services needed to support the functions, such as utility 

 services, fueling stations, repair and launching facilities, the harbor headquarters, and 

 restrooms. 



surcharge loading— Any load applied to the surface area immediately behind a retaining wall, 

 bulkhead, or embankment. 



surge— The name applied to wave motion with a period intermediate between that of the 

 ordinary wind wave and that of the tide, say from 30 seconds to 60 minutes. It is of low 

 height; usually less than 0.3 foot. 



swell— Wind-generated waves that have traveled out of their generating area. 



temperature rebars- Reinforcing bars provided primarily to resist temperature and shrinkage 

 stresses in concrete. 



tidal prism— The total amount of water that flows into a harbor or estuary and out again 

 with movement of the tide, excluding any freshwater flow. 



trailing floating slips— Floating (usually multiboat) slips that aline themselves with the 

 prevailing river current. Although they must be secured against downstream displace- 

 ment, they do not require guide piles. 



training wall— A wall or jetty designed to direct or stabilize current flow. 



transient boater— A boater within the confines of a harbor that is not his home base facility. 



tremie-poured concrete— Concrete poured under water through a tube (tremie) and cured 

 below the water surface. The placement process systematically displaces a given water 

 volume with concrete, with very little dilution of the fresh concrete by water 

 penetration. 



tsunami— A long-period wave caused by an underwater disturbance such as volcanic eruption 

 or earthquake. Commonly miscalled tidal wave. 



unwater— To pump the water out of an enclosed basin to permit construction in the dry of 

 any facilities to be built within tlie enclosure. 



updrift— The direction opposite that of the predominant movement of littoral materials. 



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