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NAUTICAL CHART MANUAL 



LOW WATER LINE (A-10) (R) 



On new chart and reconstruction Compilations and on correction Drawings the low-water 

 line shall be shown as a single row of dots. It shall be delineated whenever possible from hydro- 

 graphic surveys. However, when the hydrographic surveys do not adequately portray the 

 low water line, it shall be compiled from the photogrammetric surveys. 



When a foul limit line is shown along shore, the low-water line, if inshore of the foul line, 

 may be omitted. 



The area between the high and low-water line shaU be tinted green and, when known, the 

 character of this area such as "Sand," "Mud," "Gravel" shall be labeled. 



MARSH (Fig. 1) (C-17) 



The mean high-water line in marsh, mangrove, cypress, or similar swamp areas is generally 

 obscm-ed by vegetation and wiU not ordinarily be located on topographic surveys. In such 

 areas, the outer edge of vegetation visible above Mean High Water, usually represented by a 

 fine line on the topographic survey, presents a fairly definite shoreline to the navigator and 

 should be charted by a .006" solid Itue. 



On photogrammetric surveys, the line of change between the solid marsh and an area 

 usually flooded is indicated by a difference in symbols; on the chart, it shall be shown by a 

 fine dashed line .006" in width. 



An area shown on the photogrammetric- survey by the open marsh symbol outside the 

 high-water line shall be indicated on the charts by the word "Grass" or "Grs". If the low-water 

 line is not indicated on the survey sheets, the area shall be defined by a single row of dots 

 and shall be tinted green. Areas too small to be tinted may be indicated by tufts of grass. 

 A marsh area inside of the mean high-water line shall be represented by a green tint and black 

 legend. A black broken line .004" in width shall be used to denote the inshore limits of marsh 

 when no other symbol furnishes such a limit. Symbols for roads, railroads, levees, and bluffs 

 are examples of symbols that may replace the black dashed line. 



SURVEY 



CHART 



