On USGA-USDA Forest Service Single-Edition Quadrangle maps, how is Channel represented in Bathymetric Features?

• A. Two parallel dash lines
• B. A solid blue line
• C. Dotted line with circles
• D. A wavy blue line

Answer: (A)

On these maps, bathymetric features use blue symbols to show underwater details. A channel is indicated by two parallel blue dash lines. This style marks the boundaries of the submerged channel rather than a surface water path, so you’re reading where the channel lies below the surface. The solid blue line would usually represent a surface water feature like a stream, while the other line styles aren’t used to denote a channel in this bathymetric context. So the double-dash blue symbol specifically communicates the submerged channel location on the map.