LIVING IN THE ENVIRONMENT 17 TH MILLER/SPOOLMAN Chapter 13 Water Resources

Case Study: The Colorado River Basin— An Overtapped Resource (1) Flows 2,300 km through ______ U.S. states to the Gulf of California 14 major dams and reservoirs Located in a __________ area Water supplied mostly from ______________ of the Rocky Mountains 7 desert snowmelt

Case Study: The Colorado River Basin— An Overtapped Resource (2) Supplies water and electricity for about __________________ people Las Vegas, Los Angeles, San Diego Used to produce about ______ of the nation’s crops and livestock Very little water reaches the Gulf of California because we use _____________ of it Prolonged dry weather since __________ 30 million 15% too much 1999

Aerial View of Glen Canyon Dam Across the Colorado River and Lake Powell Fig. 13-2, p. 317 Lake Powell - _____________________ reservoir in the U.S 2 nd largest

13-1 Will We Have Enough Usable Water? Concept 13-1A We are using available freshwater unsustainably by wasting it, polluting it, and charging too little for this irreplaceable natural resource. Concept 13-1B One of every six people does not have sufficient access to clean water, and this situation will almost certainly get worse.

Freshwater Is an Irreplaceable Resource That We Are Managing Poorly (1) Why is water so important? Needed for our __________ Plays a key role in sculpting the earth’s ___________ Moderates earth’s ________________ Removes and ______________ some of the pollutants we produce Earth is a watery world….covers _______ of the planet’s surface Poorly managed resource We ______________ and _______________ it Charge too ________________ for making it available cells surface climate dilutes 71% wastepollute little

Freshwater Is an Irreplaceable Resource That We Are Managing Poorly (2) Access to water is… A global ______________ issue - World Health Organization (______) estimates that 3,900 children under age five die every day from waterborne infectious diseases An ________________ issue – vital for producing food and energy A ________________ and children’s issue – females in _______ are often responsible for finding and carrying water A national and _____________ security issue – nations often ___________ water resources health WHO economic women’s LDCs global share

Girl Carrying Well Water over Dried Out Earth during a Severe Drought in India Fig. 13-3, p. 319

Most of the Earth’s Freshwater Is Not Available to Us Only a tiny fraction of our world’s water supply is available for freshwater use: ________ Groundwater, lakes, rivers, streams Fortunately our freshwater is continually recycled, purified, and distributed by the _______________ cycle We can still _________________ this cycle though Globally people are divided into “Water _________” and Water ___________” 0.024% hydrologic overload haves have-nots

Fig. 3-16, p. 67 Condensation Ice and snow Transpiration from plants Precipitatio n to land Evaporation of surface water Evaporation from ocean Runoff Lakes and reservoirs Precipitatio n to ocean Runoff Increased runoff on land covered with crops, buildings and pavement Infiltration and percolation into aquifer Increased runoff from cutting forests and filling wetlands Runoff Groundwater in aquifers Overpumping of aquifers Runoff Water pollution Ocean Natural process Natural reservoir Human impacts Natural pathway Pathway affected by human activities

Groundwater and Surface Water Are Critical Resources (1) Ground Water Water that percolates _______________ through spaces in soil, gravel, and rock Zone of saturation Below a certain depth spaces in soil are completely ____________ with water Water table ____________ of zone of saturation…can rise or fall downward filled top

Groundwater and Surface Water Are Critical Resources (2) Aquifers Underground _______________ and porous layers of rock through which groundwater flows at a typical speed of ___________ Natural recharge – through ________________ __________________ recharge – from nearby lakes, rivers, or streams Recharge in general is very ______________ caverns 1 m / year precipitation Lateral slow

Groundwater and Surface Water Are Critical Resources (2) Surface _____________ water that does not infiltrate the ground or evaporate back into the atmosphere Watershed the land from which water ___________ into a particular river, lake, etc… Also called a ______________________ Runoff drains drainage basin

We Use Much of the World’s Reliable Runoff 2/3 of surface runoff is lost by seasonal floods 1/3 is considered _______________ runoff = usable freshwater World-wide averages of water use Domestic: 10% Agriculture: 70% Industrial use: 20% reliable Currently = use 34%By 2050 = 90%

Science Focus: Water Footprints and Virtual Water (1) Water ________________ Volume of water we use directly and indirectly to stay alive and support our lifestyles Average American uses 260 liters per day…enough to fill ______ typical bathtubs Flushing toilets, 27% Washing clothes, 22% Taking showers, 17% Running faucets, 16% Wasted from leaks, 14% World’s poorest use ________________ per day Footprint liters

Science Focus: Water Footprints and Virtual Water (2) ________________water… water that is used indirectly to provide us food and other consumer products Producing and delivering a typical hamburger requires _________________ of water (16 bathtubs) Most of which is used to grow the grain that is fed to cattle Virtual water products are ________________ by many countries so that they can save real water Virtual 2400 liters imported

Fig. 13-A, p tub = 151 liters (40 gallons) = 1 tub = 4 tubs = 16 tubs = 17 tubs = 72 tubs = 2,600 tubs = 16,600 tubs

Case Study: Freshwater Resources in the United States The U.S. has more than enough renewable freshwater, but it is _________________ distributed and much is contaminated due to _______________ and _________________ practices Our water supply is also affected by _____________ and _______________.... – a prolonged period in which precipitation is at least ________ lower than average unevenly agricultural industrial flooding drought 70%

Average annual precipitation (centimeters) Less than More than 122 Acute shortage Shortage Adequate supply Metropolitan regions with population greater than 1 million Fig. 13-4, p. 322 Why do you think that some areas with moderate precipitation still suffer from water shortages? Over use

Water Hotspots in 17 Western U.S. States Fig. 13-5, p. 322 U.S. Department of the Interior has identified 17 water hotspots in our western states At least a total of 36 states are predicted to face water shortages by 2013 due to… drought Rising temperatures Pop. growth Urban sprawl Increased water use

Case Study: The Colorado River Basin— Misuse of a Resource Why/How is the Colorado River Basin misused? 1.Extremely _____ land 2.Only a __________ flow for its size 3. A legal __________ signed by the U.S. and Mexico in 1922 (and 1944) allocated more water for human use than the river can supply 4.Since 1960, the river has rarely flowed all the way to the _____________________ 5.Receives enormous amounts of _______________ from urban areas, farms, and industries dry moderate pact Gulf of California pollutants

Water Shortages Will Grow (1) More than ________ countries – most in the Middle East and Africa – now face stress from water scarcity By 2050 some _______ countries – may in Asia – may face water scarcity Due to the growing human population…China and urbanization ______ earth’s land area experiences severe drought Will rise to _______ by 2059 from climate change % 45%

Natural Capital Degradation: Stress on the World’s Major River Basins Fig. 13-6, p. 323

Water Shortages Will Grow (2) In 2009, the United Nations reported that about 1.2 billion people ( ______________________) lacked regular access to enough clean water By 2025, it is projected that ___________________ are likely to lack enough clean water As water shortages increase, so will…. ___________________ The need for grain _____________ Food ___________ 1 out of every 6 3 billion malnutrition imports prices

Review Questions What is a watershed or drainage basin? The area where water drains into a nearby river, lake, etc.

Review Questions Why are water shortages expected to grow? What is virtual water? What is reliable runoff? Climate change Growing population Increased water use Urban sprawl Water that is indirectly used to make a product Surface water that is available for freshwater use