Solar-powered movement of water between the sea, air, and land
Follows water as it evaporates from the earth’s surface, forms clouds, and then falls back to the surface as precipitation
Cycle is continuous with no beginning or end
Provide examples for the following terms:
Water available for use:
97.2% salt water
2.8% fresh water
2.2% is in glaciers and ice caps
0.6% is groundwater
0.01% in lakes, rivers, and streams
0.001% is water vapor
Glaciers and Ice Caps
Lakes and Rivers
Uses of Fresh Water
69% for irrigation
15% for power plants, refineries, manufacturing
15% for drinking, cooking, sanitation, gardening, etc.
What steps of the water cycle can we get our water from?
For each use of water, identify if you use it directly (D), indirectly (I), or not at all (N/A).
Estimated only 0.34% of all water on earth is available for human use
Fresh water supply decreasing due to pollution:
Leaking pipelines or storage tanks
Sewage/Combined Sewer Overflow (CSO)
Any chemical, biological, or physical change in water quality that has a harmful effect on living organisms or makes water unsuitable for desired uses
Disease causing bacteria
Non-point toxic chemicals
Discharges of untreated sewage
Discharges of industrial wastes
Toxic lead, arsenic, fluoride are permanent pollutants
Slowly degradable wastes
May be there for decades, centuries, or longer
Compare and contrast point and non-point pollution.
Consider runoff. Is this a bigger concern for point or non-point pollution?
Explain why slowly degradable and nondegradable water pollution is such a concern.