Water is a seemingly abundant resource on the planet, but that perception would be incorrect. Although 70% of the Earth’s surface is covered by water, less than 1% of that is potable—fresh water that people can drink and water crops with. The rest is unusable with about 97% of it in the oceans, which are too salty for these purposes.
The average American uses about 100 gallons of water per day, depending on how you calculate water usage. The majority of that water is used in the bathroom for bathing and flushing toilets. In addition to the water used in homes, water used by businesses, industries and storm runoff needs to be treated before it is released back into the environment. While nature can clean small amounts of wastewater the billions of gallons of wastewater generated daily requires treatment plants. Once water has been treated it can be effectively released back into the environment without harmful effects to ecosystems and human health.
Review how wastewater is treated (the water that you send down the drain):
Source: USGS (n.d.) What is Wastewater, and Why Treat it Retrieved from http://ga.water.usgs.gov/edu/wuww.html
In your posts this unit answer the following questions: