1. 13-00CO
Title:
Iceberg
Caption:
Water molecules superimposed onto an iceberg.
Notes:
Hydogen bonding occurs between water molecules in ice.

2. 13-02
Title:
The Hydrological Cycle
Caption:
Diagram illustrating the water cycle.
Notes:
Water is necessary for life on our planet.

3. UN
Title:
Waterborne Disease
Caption:
Fluorescent image of the microorganisms responsible for the Milwaukee water supply contamination in The organisms are less than inches in diameter.
Notes:
Contamination of water supplies by microorganisms from human wastes can cause typhoid fever, dysentery, and cholera.

4. 13-05
Title:
Water Treatment
Caption:
Diagram illustrating the process for water purification at a municipal water treatment plant.
Notes:
Water purification is a multistep process.

5. 13-06
Title:
Wastewater Treatment
Caption:
Diagram illustrating the steps in wastewater treatment at a sewage plant.
Notes:
Wastewater treatment is a multistep process.

6. 13-07
Title:
Activated Sludge Method
Caption:
Diagram illustrating the process for treating wastewater by the activated sludge method.
Notes:
Methods for wastewater treatment involve several steps.

7. 13-TB02
Title:
Table Some Substances Found in Natural Waters
Caption:
A list of compounds and elements found in natural waters and their sources.
Notes:
Water is a mixture of minerals and covalent molecules.

8. 13-TB03
Title:
Table Some Substances Added to Water
Caption:
A list of substances found in water from the breakdown of organic matter.
Notes:
The breakdown of organic matter produces ions and covalent molecules.

9. 13-TB05
Title:
Table Drinking Water Standards
Caption:
Limits on water pollutants established by the EPA.
Notes:
Water standards are classified as primary or secondary.

10. 13-TB06
Title:
Table Summary of Wastewater Treatments
Caption:
Comparison of different wastewater treatments.
Notes:
Wastewater treatments are classified as primary, secondary, and advanced.

11. 13-TB07
Title:
Table Average Daily Water Use
Caption:
Amount of water used daily by a person for different activities.
Notes:
Water use may be direct or indirect.