Hooked on Science: Special sewer lice

Have you ever wondered how sewage water is cleaned? Using a few ingredients from around the house, you can do an experiment that will trick those around you into believing there is a sewage cleaning creature.

Materials

* Raisins

* Transparent container

* Mountain Dew

Instructions

STEP 1: Inform the children you stopped by the local sewer plant for a sample of sewer lice to observe how they clean sewage water.

STEP 2: Fill the transparent container half of the way with sewer water [Mountain Dew].

STEP 3: Drop several sewer lice [raisins] into the sewer water and observe.

Explanation

The children will eventually realize what's floating inside the Mountain Dew is not sewer lice. Inform them that once enough carbon dioxide bubbles from the Mountain Dew collect on the sides of the raisins, they "swim" to the surface. Once at the top, the carbon dioxide bubbles pop and the raisins "swim" back to the bottom. Inform the children that sewage is cleaned at a sewage plant through one, two or three stages, and not by sewer lice.

Jason Lindsey is a science outreach educator with Hooked on Science. Check out his website www.hookedonscience.org for webcasts and experiments.