water resources

The majority water (_____) is _____

97.5%; salty

And more water is inaccessible, leaving us with a tiny amount (____) readily available.

< 1%

Clean water is a ______, and water is not evenly distributed throughout the world

Renewable resource

Water that does not infiltrate the ground or evaporate is called

Surface runoff

Watershed/ drainage basin

Area of land that drains into a common area

Examples of watershed/drainage basin

River, ocean, lake, wetland

Groundwater : # 1

Evaporation and transpiration → clouds→ rain

Groundwater: # 2

Some water = runoff

Groundwater #3

Some water infiltrates then percolates

Groundwater #4

Eventually the water gets to aquifer — layer of permeable, porous rock saturated with water (groundwater)

Groundwater #5

The point where groundwater begins is called the water table, which can rise or fall with excessive rain, drought, or too much pumped out for human use

Groundwater #6

The ground above the aquifer that feeds it is called the recharge area

Groundwater #7

Aquifers typically flow to a lake or ocean (very slowly — in to ft per year)

Groundwater #8

The place where the water exits the aquifer is called the discharge area

Groundwater #9

An unconfined aquifer requires a pump to remove the water

Groundwater #10

An aquifer bound on both sides by impermeable rock and therefore under pressure is called a confined aquifer. If pierced, the water flows out readily from what is called an artesian well

Over the last century we’ve taken more baths; total use up ____ times. Per capita use up ____ times

7; 4

Who uses the most water? Ag = Ind = Dom =

70; 20; 10 %

Too little water 4 reasons

1. Drought

2. Dry climate

3. Water stress (too many people)

4. Dessication (dry out)

Pros of using dams and reservoirs

1. Hydroelectric power

2. Control flooding

3. Recreation = boosts economy

4. Guaranteed water to cities / farmland

Cons of using dams and reservoirs

1. Estuaries damaged (less water)

2. Lowers biodiversity

3. Habitat destruction

4. Deprives downstream of nutrients (farmland less fertile, aquatic life lack nutrients)

5. Costly

6. Displaces people

7. Economic losses (fisheries downstream)

Purpose of the california water project

Massive construction of aquaducts and dams to move water from northern california to southern california for agriculture and humans

Negatives of california water project

•pollutants accumulated in San Francisco Bay (less water to dilute)

• fisheries were damaged

•reduced biodiversity (mona lake)

Purpose of canada’s james bay project

Massive construction of dams to provide hydroelectric power

Negatives of canada’s bay project

• Displaced a large # of indigenous people

• caused habitat destruction and loss of biodiversity

Purpose of aral sea watershed transfer

A massive USSR project to divert water from the 2 rivers that feed the aral sea, primarily for agriculture (cotton)

many issues of aral sea watershed transfer

•local extinction of fish

•ruined crops from salt storms

•eye and lung disease in people from salt/pesticide storms

•altered climate - hotter summers and colder winters

Pros of tapping groundwater

• clean

•consistent

•cheap

•widespread

Cons of tapping water

•depletion (overdraft) - withdrawing too much

•saltwater intrusion (water from ocean gets pulled into fresh aquifer)

•subsidence (sinking of land)

•difficult to clean if polluted

Major methods of desalination

•distillation - boiling water= steam, leaving salt behind, steam then condensed into pure liquid water

•reverse osmosis- placing salty water under tremendous pressure

Major problems of desalination

•expensive

•large energy use

•disposal of brine (very salty water)

Ownership is unclear, but mainly it is

Too cheap

Solutions: use a better method, flood/furrow — center pivot — drip

<; <

Solutions of saving irrigation water #2-7

• Water when necessary- moisture water

•plant drought tolerant crop varieties

•irrigate at dawn - less evaporation loss

•implement polyculture - needs less water

•use grey water to irrigate norfood crops or golf courses

•reuse/ recycle water in industry

3 clases of water color

•white water, aka portable water = drinkable; can cook w/ it; bathe in it

•gray water = from sinks; requires less treatment

•black water = sewage water

Saving water in industry, homes and businesses

•reuse/recycle water in industry

•xeriscape - planting dry loving plants

•plant native plants

•drip irrigate flowerbeds and gardens

•fix plumbing leaks

•install meters (especially apartments)- makes people pay

•install a graywater system

•turn off sink while brushing teef

•take short showers and not bath

•do full loads of laundry only

•wash car with a hose nozzle that shuts off or patronize a carwash that recycles its water

•variable flush volumes