What do the shape and degree of slope of a hillside have to do with moving water? Does water move faster down-hill than it does on a level setting? If so, how can we find out?

We will ask a student to stand on a hilltop, or place a large object right on the top of the hill. We will stand at the bottom of the hill and sight the object or student through the straw on a clinometer. Read the angle indicated on the clinometer.

If there is a little creek flowing down the hill, we can calculate the rate of speed at which the surface water flows. We learned how to calculate this in Activity # C142.14.

If the creek is small and shallow enough, we could put a screen across the lower end, and catch the materials that the water carried (in addition to the object we floated to calculate the speed).

When you compare the shape and slope of a hill to the speed of water flowing down it and the amount of materials carried by the water, you will discover a relationship between the steepness of the slope, the speed of flow, and the amount of erosion taking place.