Water distribution system

Ask, "How does water get from natural sources of fresh water to our homes and other buildings? what is the system of water distribution in towns and cities?"

As participants volunteer responses, begin to draw a flowchart of the water and sewage system. Draw it on a flipchart paper so you can keep it and use it in activities that come up later in this unit. Draw and label the various stages of the water distribution system, starting with natural sources of water and ending with water users, such as homes, etc. You may have to ask questions to prompt thinking about any stages that the group doesn't come up with on its own. The stages include:

• pumping station that brings water from the source of surface water (eg. lake) into the distribution system
• wells to bring groundwater to the surface
• treatment plant to purify the water
• reservoir where the water is kept ready for further distribution
• pipes that take water into homes, and other buildings
• from homes, industries, etc. pipes that take sewage away
• sewage treatment plant

Ask, "what happens if untreated sewage goes back into the natural source of water?" Add the word pollution to the flipchart.

Brainstorm a list of causes of water pollution:

• fertilizers
• industrial wastes
• pesticides
• seepage from landfills, mining operations and industrial sites
• seepage of animal wastes from factory farms
• domestic sewage
• radioactive materials
• thermal pollution from cooling towers
• dumping of garbage