
Water Maps
How to Read Blue Lines on a Map
Learn how to read blue lines on a map by tracing their connections, comparing local detail and interpreting the…
Make sense of the lines, symbols and limits on maps of water.

Learn how to read blue lines on a map by tracing their connections, comparing local detail and interpreting the…
Look at the channel, the surrounding ground and the route downstream. Each offers a different clue; none tells the whole story alone.