Freshwater Resources Unit C Chapter 2

Earth’s Waters Most of Earth’s water is 97% percent salt water that is found in oceans. Only 3% is fresh water. 76% ice masses .037% atmosphere (water vapor in a gaseous form. Less than 1% is fresh water available for human use. Some of the Earth’s fresh water is deep underground.

Distribution of Water on Earth

Freshwater available for human use Earth’s water supply Actual % on Earth Oceans Glaciers/Icecaps Groundwater Atmosphere Freshwater Lakes Saline lakes/Inland Seas Soil Moisture Rivers Easily available amount of freshwater*

Freshwater available for human use Earth’s water supply Actual % on Earth Oceans 97.2% Glaciers/Icecaps 2%* Groundwater .62%* Atmosphere .009%* Freshwater Lakes .008%* Saline lakes/Inland Seas .001%* Soil Moisture Rivers .0001%* Easily available amount of freshwater* 2.6291%

Why is water so important??? Our bodies are more than ½ water – our bodies need it to survive! We use it for many things….

Almost everything you do requires water…. Showering, brushing teeth, washing dishes and clothes,… And even eating a pizza! Farms need water to grow the tomatoes and wheat for your pizza, the cheese comes from a cow that drank water and the grain is grown using water.

The major ways people use water: * Farming – about 40% of water used in the U.S. goes toward crops and livestock Irrigation: supplying water to land (from aquifers, rivers, or lakes) to grow crops

The major ways people use water: Industry – water used to: Cool down machines Separate chunks of coal when mining Example: Process of making 1 car can require about 50x the car’s weight in water – the process begins with the mining of minerals and ends with the final washing as the car rolls out of the factory

The major ways people use water: Transportation Recreation

The major ways people use water: Fisheries & Aquaculture The science and business of raising and harvesting fish in a controlled situation. Negative: Can cause pollution! Positive: Helps maintain population of fish in rivers & lakes

The major ways people use water: ENERGY Dams Hydroelectric dam: as water rushes through, the dam turns turbines that generate electricity. May also be used to create a reservoir Potential problem: Blocks flow of rich soil to valley below dam Fish cannot reach breading grounds – “fish ladder” Locks

Locks Lock system video

Society depends on clean and safe water Fresh water can contain a variety of harmful substances and organisms – some are present naturally, others are there because of pollution. When the concentration of these substances are high, they can harm people

Society depends on clean and safe water Substance Common Source Max Allowed in Parts Per Million Copper Natural deposits; household pipes 1.3 Cyanide Various factories 0.2 Lead 0.015 Mercury Natural deposits; refineries & factories; landfills; crop fields 0.002 Nitrite Water running off fertilized fields; sewage leaks; natural deposits 1 EPA sets standards for safe, clean drinking water Water providers test water in their area and compare with EPA standards

Treatment of Drinking Water Clean water - how it's made

Sewage Systems Collects and treats wastewater from a city or town

Sources of water pollution Point-source pollution Pollution is easy to spot and laws can be enforced to stop it

Sources of water pollution Nonpoint-source pollution Runoff from streets, lawns, construction sites, etc

Sources of water pollution Homes Cities Sewage Farms Shipping, Boating, & Oil Transport

Water pollution can be PREVENTED Factories can maintain pipelines and equipment Inspect transportation to ensure there are no leaks Reduce amount of toxic waste from industries Construction companies can design projects to reduce pollution that new construction can cause New techniques in farming Choose organic foods Proper disposal of chemicals

Water shortages threaten society Global problem Overuse can cause water shortages Americans use an average of 80-100 gallons of water each day!

Conservation Use less water Reuse water Recycle water There are so many things we can do!