CHANNEL - (1) A natural or artificial waterway of perceptible extent which 

 either periodically or continuously contains moving water, or which 

 forms a connecting link between two bodies of water. (2) The part of a 

 Body of water deep enough to be used for navigation through an area 

 otherwise too shallow for navigation. (3) A large strait, as the English 

 Channel. (.4) The deepest part of a stream, bay, or strait through which 

 the main volume or current of water flows. 



CLAY - A fine grained soil with cohesive strength inversely related to water 

 content. It is plastic when moist and hardens when baked or fired. See 

 SOIL CLASSIFICATION. 



CLIFF - A high, steep face of rock; a precipice. 



CLOGGING - The phenomena causing either a reduction in, or the elimination 

 of, the permeability of the filter. 



COAST - A strip of land of indefinite width (may be several miles) that 

 extends from the shoreline inland to the first major change in terrain 

 features. 



COASTAL AREA - The land and sea area bordering the shoreline. 



COBBLE (COBBLESTONE) - A naturally rounded stone larger than a pebble, 

 especially one 6 inches to a foot in diameter. 



COLLECTOR PIPE - A pipe capable of collecting and carrying water from the 

 soil. 



COLONIZATION - A natural phenomenon where a species invades an area pre- 

 viously unoccupied by that species and becomes established. To be 

 successful the species must be able to reproduce in that area. 



CONTOUR - A line on a map or chart representing points of equal elevation 

 with relation to a DATUM. It is called an ISOBATH when connecting points 

 of equal depth below a datum. 



CORAL - (1) (Biology) Marine coelenterates (Madreporia) , solitary or 

 colonial, which form a hard external covering ,of calcium compounds, or 

 other materials. The corals which form large reefs are limited to warm, 

 shallow waters, while those forming solitary, minute growths may be 

 found in colder waters to great depths. (2) (Geology) The concretion of 

 coral polyps, composed almost wholly of calcium carbonate, forming reefs, 

 •and treelike and globular masses. May also include calcareous algae and 

 other organisms producing calcareous secretions, such as bryozoans and 

 hydro zoans. 



CORE - A vertical cylindrical sample of the bottom sediments from which the 

 nature and stratification of the bottom may be determined. The interior 

 material of a breakwater or groin. 



CREEP - To slip or become slightly displaced; specifically of metal to shift 

 longitudinally under weight. 



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