The name for a smaller stream that flows into a larger stream. 

The act of adding water to crops.

A pit, hole, or shaft sunk into the earth to tap an underground source of water.

Lack of preciptation for a long period of time.

The temperature at which water changes from a solid into a liquid or vice versa.

Yes.

The chemical symbol for water.

The wearing down or washing away of soil and land by the action of water or ice.

Tanks used to hold waste from homes when a sewer line is not available.

This element is added to water to prevent tooth decay. 

The average number of gallons of water treated in the United States for each person every day. 

This is where the majority of the world's fresh water is stored and is inaccessible.

Two possible sources of groundwater contamination.

The process by which a vapour becomes a liquid or a solid.

A term used to describe the area drained by a river and its tributaries. 

A place where water is treated to make it safe to drink.

The percentage of the earth covered with water.

15 seconds.

The source of erergy for the hydrologic or water cycle.

The five great lakes.

The capacity of porous materials, such as sand and gravel, to transmit water.

Water-saturated lands where equatic plants and animals live.

The percentage of the human body composed of water.

Less than 0.007%

The percentage of the earth's water that is fresh water.

The three largest oceans.

The movement of water down through the earth's surface.

The change in the quality of water that makes it unsuitable for certain uses.

On average, almost 26% of the water used in a home is to do this.

The temperature at which water changes from a liquid ro a gas or vice versa.