US Water Sources and Usage

Population density - 1980

http://www.nationalatlas.gov/natlas/Natlasstart.asp

Population density - 2000

http://www.nationalatlas.gov/natlas/Natlasstart.asp

Trends in population and freshwater withdrawals 1950-2000

http://pubs.usgs.gov/circ/2004/circ1268/

Average annual precipitation1961-1990

http://www.nationalatlas.gov/natlas/Natlasstart.asp

Streams and waterbodies

http://www.nationalatlas.gov/natlas/Natlasstart.asp

U.S. Aquifers

US water use 2000

http://pubs.usgs.gov/circ/2004/circ1268/

408 billion gallons of water per day

withdrawn in 2000

Public water use

http://www.nationalatlas.gov/natlas/Natlasstart.asp

43 billion gallons of water per day

withdrawn in 2000

Industrial water use

http://www.nationalatlas.gov/natlas/Natlasstart.asp

20 billion gallons of water per day

withdrawn in 2000

Water used for irrigation

http://pubs.usgs.gov/circ/2004/circ1268/htdocs/figure07.html

137 billion gallons of water per day

withdrawn in 2000

Water used for irrigation

http://ga.water.usgs.gov/edu/wuir.html

Irrigation techniques• Flood irrigation

– Simple and cheap– 50% of water wasted

• Drip irrigation– Low pressure and volume

systems– Water applied directly to the

root zone– Approx. 70% efficiency

• Spray irrigation– Up to 35% of water lost due to

evaporation

• Low-energy spray irrigation– Nozzle very close to ground– Up to 90% efficiency

http://ga.water.usgs.gov/edu/wuir.html

http://pubs.usgs.gov/circ/2004/circ1268/htdocs/figure12.html

195 billion gallons of water per day

withdrawn in 2000

Water used by thermoelectric power plants

• Steam-driven turbine generators

• Cooling power-producing equipment

• Used water has to be cooled before release

http://ga.water.usgs.gov/edu/wupt.html

Total water withdrawals by state

http://pubs.usgs.gov/circ/2004/circ1268/

World Drinking Water Coverage

http://www.who.int/water_sanitation_health/monitoring/jmp04_3.pdf

Activities

• Hydrology trivia quiz

http://interactive2.usgs.gov/learningweb/fun/trivia_water_1.htm

• How would you handle this water crisis?

http://ga.water.usgs.gov/edu/sos3.html