How must contour lines bend on a topographic map to indicate a stream valley?

Answer 1

If the stream valley is very deep they will be close together and will follow the path of the stream bed.

Answer 2

Down

Because water erodes and cuts a channel it will be at a lower elevation than the rest of the ground around it. You can tell if there is a stream, river or creek by a pattern of V shaped contour lines and the bottom of the V points in the direction that the river is running. This is because it will be at a lower elevation than the ground around it. Most valleys are formed by the action of a river or stream that runs or ran through it, cutting the channel. So the same will be true for a valley.

Of course you have to check the contour lines to see which direction is up hill and remember that water runs downhill so the sides of the river will be higher than the bottom of the river forming that V shape.

When the contour lines get close together they indicate a drastic change in elevation like a steep river valley or a cliff. Old river beds or creeks that only have water in them during part of the year won't necessarly have a blue river running down them showing running water. This is why it is important to know the direction of the contour lines that signifiy a river.

Needless to say reading maps is a hugly important skill in the Army because if you try to cover land you need to recognize a dry river bed or a cliff that can't be crossed easily. So map reading and contour lines is taught in Basic Training.

Answer 3

Each of the lines on a contour map represents an elevation. Some of the line are likely marked with their elevation so you can determine what the contour scale is. If the lines are close together it indicates a significant change in the elevation - showing high spots and low spots. The low spots are the path the water is going to follow. Where the lines are further away from each other is where the land is flatter.

Answer 4

Instead use blue lines to indicate water systems