Contour Lines and Water Flow: What’s the Relationship?

Understanding Contour Lines and Water Flow

When navigating a map, it’s essential to understand the relationship between contour lines and water flow. Contour lines are the lines on the map that connect points of equal elevation. A contour line may be drawn at intervals of 10, 20, or 30 feet, depending on the map scale and the terrain. The closer the contour lines are together, the steeper the slope is between them.

To identify water flow on a map, look for a series of small arrows or ‘V’s that point downhill. This indicates the direction of water flow, which can be a stream, river, or even a dry wash. When following a contour line, the direction of water flow is often indicated by a change in the contour line’s orientation. For example, if a contour line turns sharply to the right, it may indicate a bend in the water flow.

Identifying Water Sources and Flow Paths

To identify potential water sources and flow paths on a map, look for areas where the contour lines converge or create a ‘V’ shape. This indicates a low-lying area that may collect water and create a source. Water flow paths can be identified by following the contour lines downhill, using the arrows or ‘V’s as a guide. When following a contour line, pay attention to the change in elevation and the orientation of the line to determine the direction of water flow.

Practical Applications

Understanding the relationship between contour lines and water flow has practical applications for outdoor enthusiasts, such as hikers, backpackers, and kayakers. By identifying potential water sources and flow paths on a map, you can locate areas with reliable water sources, avoid areas with fast-moving water, and plan your route accordingly. This knowledge can also help you navigate through dense vegetation or rugged terrain, where water flow paths may be obscured.