STRUCTURE REPAIR - Correction of damage to coastal structures, in most 

 cases replacement of damaged sections of a pile. 



TIDAL ESTUARY WATER LEVEL - Control of tidal flow and water elevation in 

 the part of a river affected by tides to permit navigation, energy 

 production, or storm protection. 



TIDAL ESTUARY WATER QUALITY - Control of tidal flow in the part of a river 

 affected by tides to restrict the upstream movement of saltwater or 

 to flush polluted water from stagnant parts of the estuary. 



TIDAL INLET - Coastal structures that may be used in the short waterway 

 between a tidal bay or lagoon and the parent body of water or at the 

 mouth of a river where it flows into a large tidal body of water. 



TIDAL MEASUREMENT - Determination of tidal height, current velocity, 

 and period. 



TIRES - Scrap tires used as structural units in coastal structures such 

 as floating breakwaters or revetments. 



TOW WINCH CONTROL - Operation of a tow winch to launch, retrieve, or 

 control the depth of a towed instrument. 



TOWED BODY DEPTH CONTROL - Operation of position control devices on 



towed instrtnnents which, for example, regiilate buoyancy of seismic 

 streamer cables or manipulate diving planes on towed vehicles. 



TOWED VEHICLE - A body containing or attached to a towed Instrument to 

 provide streamlining or buoyancy, or to control position, accelera- 

 tion, or vibration. 



TOWING CABLE - Cable for towing instruments, usually equipped with 

 electrical conductors and fairings. 



WATER PLANT REMOVAL - Removal of shallow-water weeds, to improve navi- 

 gation or recreation in a body of water, by cutterhead dredges with 

 special apparatus for cutting and shredcjing plants or by plant- 

 harvesting watercraft with digging jets for uprooting plants and 

 conveyors for removing them from the water. 



WAVE ABSORBER BEACH - A wave-absorbing barrier or mattress to be placed 

 in a model basin or on a beach face, a typical mattress being of 

 loosely woven or perforated material which, unlike a revetment, 

 does not cover the whole area with durable material. 



WAVE FLUME - A facility using wave motion for research, educational 

 demonstrations, or recreational activities. 



WAVE GENERATOR - A means for making waves in a flume or model basin. 



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