[Free Registration/Login may be required to access all resource tools.] Describes the sources of water pollution, such as municipal, industrial, and agricultural.

The USGS explains the definition of a river and how a river is supplied with water. Included is a cross section of a river. Click Home to access the site in Spanish.

Students carry out a number of activities that demonstrate the concepts of evaporation, condensation, precipitation, and soil moisture and runoff. Then students construct a terrarium as a way to observe the water cycle. Immediately...

See how the topography and gravity affect the distribution and flow of Earth's water.

In this activity, students investigate a large watershed, look for sources of pollution in the watershed, and study the impacts of a rain storm on a watershed and estuary, without going on a field trip. Students investigate the nature of...

See how rainwater and snow melt flows from high areas to low areas which ultimately results in Earth's groundwater.

The National Weather Service offers information on the processes that make up the water (hydrologic) cycle, including evaporation and transpiration, precipitation, run-off, infiltration, and percolation. Has a good illustration and...

Students explore the chemistry behind the causes and effects of acid mine drainage on a modeled river. In this activity, students examine the chemistry of acidic mine runoff and its effects on river water.

Lake Mattamuskeet-so named by Algonquian Indians-is North Carolina's largest natural lake. The ancient body of water has not escaped man's intervention. Originally, Mattamuskeet was a shallow, self-contained lake without creeks or rivers...