Using Water WiselyChapter 11 section 4 S6E5.i Describe methods for conserving natural resources such as water, soil, and air.
You will be able to ……………….………… • Identify two forms of water pollution • Describe two ways that wastewater can be treated. • Describe how water is used and how water can be conserved in industry, in agriculture, and at home.
While hiking, you realize your canteen is almost empty. Why should you not fill the canteen with water from the nearby stream? Even though the water may look clean, it might contain pollutants or bacteria.
Water Pollution • What is pollution? • Where does the waste come from? • The introduction of harmful substances into the environment. • Cities, factories, and farms
Point-source pollution • It comes from a specific site. • It can be controlled because its source can be identified.
Nonpoint-source pollution • It comes from many sources. • Reaches bodies of water by runoff. • Examples: street gutter, fertilizers, eroded soils, salts from irrigation. Hardest to Control
Health of a Water SystemProperties of water influenced by water quality? • Dissolved Oxygen (DO) – this is the oxygen that is dissolved in water. • Levels below 4.0 mg/L in can cause stress and death for organisms in the water. • Sewage, fertilizer runoff, and animal waste can decrease DO levels. • thermal pollution (increase in water temperature) causes a decrease in DO levels. Ex: nuclear power plants • Cold water holds more oxygen than warm water
Nitrates are naturally occurring compounds of nitrogen and oxygen. • Small amounts normal, elevated harmful • Lower DO levels • Examples: animal wastes or fertilizers that seep into groundwater.
Alkalinity refers to the water’s ability to neutralize acid. -too much acid (ph below 6.0), harmful to organisms living in water.
Cleaning polluted water • Sewage treatment plant • A facility that cleans the waster materials found in water that comes from sewers or drains. • Septic Tank • A large underground tank that cleans the wastewater from a household by separating solid waster from liquids. • Bacteria breaks down the solid waste.
Where is water used? Home Average 100 gal per day Industry 19% Agriculture
Ways to Conserve water>>>>>>Only use water that is needed<<<<<< • Industry: recycle water • Agriculture: drip irrigation system • Household: low-flow shower heads and low-flush toilets, time your showers, only wash dishes and clothes when there is a full load.