This demonstration shows how ground pollution and upstream water pollution can be carried downstream to other bodies of water and land. The “ground” in the stream table model has been polluted with green food coloring (before the water is added). As the water passes over the polluted area, the pollution contaminates the stream, surrounding land and the larger body of water at the end of the steam.
After polluted water has entered into larger bodies of water (seas, gulfs and oceans), it can be spread to other areas by the Coriolis effect. The Coriolis effect is caused by the rotation of the Earth. The effect deflects objects moving along the surface of the Earth to the right in the Northern hemisphere and to the left in the Southern hemisphere. The resulting movements can cause pollution to spread far beyond its source and affect other parts of the world.
For this activity, stream table models are utilized. Students introduce pollutants into the sediment in the stream table. Then they introduce water into the stream table and observe the sediment and “downstream” waterway.