Ecology & Environmental Problems

Dr. Ron ChesserSpring 2004

WaterReading: Chapter 20

Where is the Water?

• Oceans: ~97%

• Ice Caps and glaciers: ~2%

• Ground Water: ~0.3%

• Lakes

• Atmosphere

• Rivers, Streams,

How much water do we use?

Water Usage in the USA

USA water use…

• USA uses 338 Billion Gallons of Water per day (1.3 trillion liters)

• 1,400 gallons/person• USA uses almost 2x the average

European Country– 41% Agriculture– 38% power plants– 11% industry– 10% general public

Gallons of Water to Produce…

• 1 egg: 40 gallons• 1 glass of milk: 100 gallons• 1 pound of flour: 75 gallons• 1 pound of rice: 560 gallons• 1 pound of beef: 800 gallons• 1 Sunday paper: 280 gallons• 1 pound of Aluminum: 1,000 gallons• 1 car: 100,000 gallons

Water Use: Family of Four / day

• Toilet flushing: 100 gallons

• Shower/bath: 80 gallons

• Laundry: 35 gallons

• Dishwashing: 15 gallons

• Bathroom sink: 5 gallons

• Lawn: 100 gallons

• TOTAL: ~335 gallons/day

Water Consumption

• Consumed Water --- withdrawn but not returned to its source

Lost to the local water cycle

About 25% of all water withdrawn in the USA is consumed.

Industry is the major withdrawer of water, but Agriculture is the major (80%) consumer of water in the USA

Water Conservation

• Flush less: “If its yellow, let it mellow. If its brown, flush it down.”

• Low flush toilets

• Sprinkler regulations

• Make water expensive

• Build more dams

Dams

• Inhibit flooding• Provide Irrigation• Provide recreation• Enable hydroelectric• Drinking water

• Disrupt sediment flow• Loss of land

resources• Increase salination• Alters water chemistry• Alters fish migration• Alters fish ecology

IrrigationAlmost 60 percent of all the world's fresh water

withdrawals go towards irrigation uses.

Only 37% of water Used in irrigationIs taken up by the plant.

Since 1955 the amountOf irrigated land hasTripled.

Water Levels in Texas

• Ground water use: – By 2020 volume will be reduced to 37% of

1979 supply level– By 2010 output will be reduced by 8.1%

from 1970’s

What to do?

1. Use it all now…

2. Try to conserve…

3. Return to dry land farming…

Ogallalah and Floridan Aquifers

Edwards Aquifer

Ogallala Aquifer Facts

• Covers 11% of state of Texas• 3.3 Billion Acre feet• Would fill 100% of Lake Huron plums 20% of

Lake Ontario• Cover all 50 states with about 6” of water• Require about 6,000 years to refill• 170,000 wells (50,000 in NW Texas)• 90% Irrigation use (3 – 900 feet thick)• Plan (T. Boone Pickens) to sell groundwater

from Panhandle to San Antonio, Dallas and El Paso

Surface and Ground Water

Growing Use Patterns

Ground Water Uses in the USA

Where is water?

Ground Water

Industrial Water Use5 Companies use 90% of water

• Chemical Production

• Paper and Pulp Production

• Petroleum & Coal (Thermoelectric)

• Primary metals production

• Food Processing

Thermoelectric Power

Water for Thermoelectric Power

Water for Thermoelectric Power

Why the Decrease?

Too Much WaterIn the United States, the average annual cost of flood damage is more than $2 billion. Each year about 100 people lose their lives to floods.