Freshwater Resources

Chapter 12

Lesson 1 Main Ideas

• Fresh water supports life

• Most human activities require water

• Dams and other structures alter rivers

Why is water so important to

humans? • Human body is mostly water (blood, skin, etc)

• No one can live without water more than a few days

• People use water to grow food

• Water is used for transportation of people and goods

U S cities near water

• Portland, Oregon

• Omaha, Nebraska

• Cleveland, Ohio

• Pittsburgh, Pennsylvania

• St Louis, Missouri

• New Orleans, Louisiana

• San Francisco, California

Activities require water

• Shower, brush teeth, clean dishes and clothes, cook, fill pools, grow crops, making paper, generates electricity, mining, etc...

• Farming, Industry, Transportation, Recreation, Fisheries and Aquaculture, Energy

Farming• 40% of the water that is used goes to

growing crops and raising livestock (eating)

• Farmers near dry areas must irrigate water- draw water from aquifers, rivers, or lakes

• Over half US farms use flood irrigation instead of spray irrigation

Industry

• Factories use water to make cars, notebooks, jeans, shoes, skateboards, and televisions- almost all products

• Water used in factories can be used again or cleaned and returned to lakes or rivers

Transportation & Recreation

• Trading goods or visiting areas

• Rafting, canoeing, kayaking, camping, picnicking, swimming, fishing, etc...

• Canals sometimes are built as a bypass or to connect waterways

Aquaculture • Fresh water is full of life! Tiny one celled

organisms, shrimp, worms, fish, etc…

• Food is provided to humans and to other animals like frogs, insects, birds, etc…

• Fish farming is very popular for catfish, trout, salmon-only problem is excess nutrients flowing into rivers

• Fish hatcheries help threatened species survive

Energy

• Force of water powers machines

• Water generates electricity

• Water is used to cool nuclear power plants

Altering Rivers

• Landscape changes when dams are built

• Ecosystems are changed when dams are built

• Canals are used to connect rivers

• Dams can cause flooding

Lesson 2 Main Ideas

• Treatment makes water safe for drinking

• Waste water is treated and released

• Water pollution comes from many sources

• Water pollution can be prevented

Drinking Water

• From wells or reservoirs

• Stored in tanks

• Flows through pipes to buildings

• May contain impurities or organisms that cause disease

Water Quality

• Environment Protection Agency (EPA) sets standards for safe clean drinking water

• Towns also have laws for safe water-Prattville Water Works constantly tests our water to make sure it is clean and safe

• If water is contaminated, it must be treated before used

Water Contaminates

• Chlorine and fluoride

• Copper, Lead and other metals

• Cyanide and Mercury

• Etc…

Treatment

• Water is piped into plant from lake or river

• Disinfecting can clumping occurs to collect dirt and bacteria

• Clarifying is next to make it clear

• Tiny particles are filtered by flowing through coal, sand and gravel

• Chlorine is added to kill bacteria then it is stored

Waste Water

• Waste water is treated with sewage or septic tanks

• Each city/town has a sewage system to carry waste water from building to the treatment plant

Sewage

• To begin with it is strained and sits to allow sludge to sink to bottom then removed

• Chlorine is added to kill about half bacteria

• Oxygen is pumped in and grease skimmed off the top

• Chemicals clean water and pump it back out

Septic Systems

• Used by a home or business (not town)

• Sludge settles to bottom of tank and is consumed by bacteria. Some sludge has to be removed from tank every few years

• Water exits tank and spreads and sinks into the ground

Water pollution • Humans make fresh water contaminated too.

• Homes-household chemicals and pesticides

• Cities-Toxic chemicals, Motor oil

• Sewage-dumping raw waste

• Farms-animal waste and fertilizers/pesticides

• Shipping-oil spills

Prevention • When water is polluted, there is less

fresh water to use. Polluted water can endanger our health.

• Pass laws to limit dumping, recycle and reuse, stop leaks, decrease pavement, inspect vehicles

• Fence animals on farms, organic foods, proper disposal of all hazardous waste

Lesson 3 Main Ideas

• Water shortages are a global problem.

• Overuse can cause water shortages.

• Fresh water can be conserved.

• People can balance water needs and uses.

Global water

• Many nations have severe fresh water shortages.

• Water supply is dwindling all over the world due to population growth (feeding)

• Aquifers are being emptied faster than they are refilling

Overuse • Agriculture uses most of the water around the

world but only half the water used on plants reaches the roots-other evaporates or runs off

• Seven states use water from the Colorado river. About half a billion people in 31 countries currently face water shortages. 3 states and Mexico share Rio Grande water

• Aquifers are emptying and river levels are decreasing-both take years to refill

Conserve • It’s not hopeless! Three ways to

conserve:

• 1) repair leaks 2) reuse water 3) recycle water

• Farmers conserve using drip irrigation, factories reuse water, modern plumbing in homes, shorter showers, turn off water, etc

Balance

• People need to balance needs and uses.

• Debates in our town, state, country on what is a need – pools, lawns, hydration, grow food, make products, etc…

Some Solutions • World Food Program -International

organization that provides food to countries experiencing drought. United Nations has food aid.

• States and countries make agreements about shared rivers and lakes and pollution levels

• Possible solution for future: pipeline for fresh water from Alaska to travel to California

New Solution

• Desalination-process of removing salt from the ocean

• Dry regions like Israel. Coastal areas like California and Florida.

• This process is difficult and expensive

• Icebergs-obtain fresh water from iceberg but the thawing and transportation is costly

U.S. Water Uses

• Americans use an average of 168 liters per person each day!

• 29% toilet flushes, 21% washing clothes, 21% showers, 12% faucet drain, 9% bath tub, 3% washing dishes, 5% water leaks

Conclusion

• Fresh water is a valuable natural resource that needs to be protected and not taken for granted!