Title: 13-4 Is Transferring Water from One Place to Another the Answer?
113-4 Is Transferring Water from One Place to
Another the Answer?
- Concept 13-4 Transferring water from one place
to another has greatly increased water supplies
in some areas, but it has also disrupted
ecosystems.
2Water Transfers Can Be Wasteful and
Environmentally Harmful
- Using a lot of water to produce a water thirsty
plant, like ________________, is not necessarily
a bad thingif the crop is grown in areas with
___________ of water - However, U.S. lettuce primarily comes from
Californias _____________ Central Valley area,
and requires the use of heavy _________________
lettuce
a lot
arid
irrigation
3Southern California Lettuce Grown with
________________ California Water
Northern
Fig. 13-15, p. 331
4California Transfers Water from Water-Rich Areas
to Water-Poor Areas
transferred
- Water ________________ from north to south by
- Tunnels
- Aqueducts
- Underground pipes
- This water transfer project is called the
___________________ ___________ ___________ - ___________________ water use in arid regions
- Environmental damage to _______________ River and
San Francisco ___________
California
Water
Project
Inefficient
Sacramento
Bay
5CALIFORNIA
NEVADA
Shasta Lake Oroville Dam and
UTAH
Sacramento River
Reservoir
Feather River
Lake Tahoe
North Bay Aqueduct
Sacramento
SIERRA MOUNTAIN RANGE
San Francisco
South Bay Aqueduct
Hoover Dam and Reservoir (Lake Mead)
Fresno
San Luis Dam and Reservoir
San Joaquin Valley
Colorado River
Los Angeles Aqueduct
California Aqueduct
ARIZONA
Colorado River Aqueduct
Santa Barbara
Central Arizona Project
Los Angeles
Phoenix
Salton Sea
San Diego
Tucson
MEXICO
Fig. 13-16, p. 331
6California Transfers Water from Water-Rich Areas
to Water-Poor Areas
- Projected climate change may make situation
worse - snow packs in the _________ ______________
mountains may - melt _________________
- Receive ___________ precipitation during drought
years - Some analysts project that during this century,
many people living in arid, Southern California
cities, will have to _______________ elsewhere
High
Sierra
faster
less
move
7Case Study The Aral Sea Disaster (1)
- The ___________ Sea was once the worlds
_______ largest lake -
- 1960 has been used for a large scale water
transfer to irrigate one of the driest areas in
central _____________ - Cotton and rice
Aral
4th
Asia
8Natural Capital Degradation The Aral Sea,
Shrinking Freshwater Lake
Fig. 13-17, p. 332
9Case Study The Aral Sea Disaster (2)
- The large scale water transfer was also coupled
with - _____________________
- High ________________ rates
- Since 1961
- Water levels have dropped by an amount equivalent
to a _____________ building - the seas salinity (___________ content) has
risen _________________________
drought
evaporation
6-story
salt
seven-fold
10Case Study The Aral Sea Disaster (2)
- 85 of the areas ________________ have been
eliminated - ___________ of local bird and mammal species have
disappeared - Devastated the areas ______________ industry
- The southern portion of the Aral Sea is now a
desert covered with glistening white
_______________
wetlands
Half
fishing
salt
11Case Study The Aral Sea Disaster (2)
- Wind-blown salt and dust ________________ other
fields and wildlife areas - Settling on the __________________ in the
Himalayas causing them to melt at a ____________
rate - To increase yields, farmers are using _________
herbicides, insecticides, and fertilizers, which
have percolated into the ___________________
pollutes
glaciers
faster
more
groundwater
12Case Study The Aral Sea Disaster (2)
- People living in the Aral Sea watershed have
experienced increasing ___________ problems due
to all of the pollution - Anemia
- Respiratory illnesses
- Liver and kidney disease
- Eye problems
- Various cancers
health
13Case Study The Aral Sea Disaster (2)
- Since 1999, the United Nations and World Bank
have spent about 600 million to - _________________ drinking water
- _______________ irrigation and drainage systems
- Neighboring countries have been replacing
water-thirsty crops with others that require
________ irrigation - ___________ was built to raise lake levels in the
Northern Aral Sea
purify
improve
less
Dike
1413-5 Is Converting Salty Seawater to Freshwater
the Answer?
- Concept 13-5 We can convert salty ocean water to
freshwater, but the cost is high, and the
resulting salty brine must be disposed of without
harming aquatic or terrestrial ecosystems.
15Removing Salt from Seawater Is Costly, Kills
Organisms, Creates Briny Wastewater (1)
- Desalination - removing dissolved salts from
ocean water or from _____________ (slightly
salty) water in aquifers or lakes - Two most widely used methods are ________________
and _______________ osmosis - Distillation uses
- heat to evaporate water, leaving salts
______________ - Cool or ___________________ steam back into
liquid water
brackish
distillation
reverse
behind
condense
16Removing Salt from Seawater Is Costly, Kills
Organisms, Creates Briny Wastewater (1)
- Reverse osmosisalso called _________________
- Uses high ______________ to force salt water
through a membrane _____________ with pores that
are small enough to remove the salt - Currently there are about ________________
desalination plants mostly in arid areas of - Middle east
- North Africa
- Caribbean
- Mediterranean
microfiltration
pressure
filter
14,450
17Removing Salt from Seawater Is Costly, Kills
Organisms, Creates Briny Wastewater (2)
- Three major problems with the widespread use of
desalination - High __________ and energy footprint
- Chemicals are required to keep down ___________
growth____________ many marine organisms - Produces huge quantities of ____________ salts
that must go somewhere - Bottom Line Currently, desalination is
practical only for water _____________,
_______________ countries
cost
algal
kill
waste
short
wealthy
18Science Focus The Search for Improved
Desalination Technology
- Improved desalination?
- Using other forms of energy to power plants
- _____________________
- _____________________
- _____________________
- Using ___________ to carry desalination equipment
instead of land-based desalination plants - Use water from depths ______________ where most
marine organisms live - The remaining salt or _____________ could be
carried away from the coast and
___________________
solar
wind
ocean waves
ships
below
brine
diluted
19Review Questions
- What are some disadvantages of transferring
water? - What are some disadvantages of using desalination
methods?
inefficient
Dries other areas (ecological damage)
Pollution
High cost
High energy needs
Chemical use and salt waste