The legal right to use water from a river, stream, or other body for a purpose.

The water that is beneath Earth's surface.

Waste from production of consumer goods, mining, agriculture and petroleum extraction and refining.

A barrier constructed to hold back water and raise its level, the resulting reservoir being used in the generation of electricity or as a water supply.

Small groups of nomadic people in Arabia.

Limited quantities of resources to meet unlimited wants.

Electricity made by water power.

Water from farm fields due to irrigation or rain that flows over the earth and is absorbed into the ground or flows into bodies of water. Also can contain pesticides and herbicides.

The contamination of streams, rivers, lakes, oceans, or groundwater with substances produced through human activities.

Having little or no rain; too dry or barren to support vegetation.

Fertile spot in a desert where water is found

To fill up or build up again

The presence in or introduction into the environment of a substance or thing that has harmful or poisonous effects

The presence in or introduction into the air of a substance which has harmful or poisonous effects

Examples: Countries that dam rivers, living in a desert not near fresh water, polluted water sources, and large population groups in large cities.