Did you ever think of water as a road? Not the kind of road you walk or drive on, but as a transportation system. Water moves, or transports, all different kinds of materials. Materials can be lots of things - from tiny specks of soil or sand, to small twigs or leaves to branches and entire trees! It can also be small pebbles or large rocks. Material is always on the move in streams.

A stream is a balance between water and material. When the amount of water or material changes, it takes time for the stream to become balanced again. Before reaching a balance, or equilibrium, the stream may wash away some of the bank. Or the stream may deepen, or add material to the bottom to make it shallower.

Sediment is soil moving in streams. When a stream has a lot of sediment in it, what color do you think it will be? Streams with too much sediment in them mean problems for fish. (Look for the "riffle hotspot" in the creek panorama to learn why.)

If You Don't Want To Be Considered A Watered Down Hydrologist, Here Are A Few Things To Remember:

Rivers are like roads. They're transportation systems for many kinds of materials.

Streams are water and materials in balance. Too much water or too much material causes changes in the stream.