Useful Terms & Concepts

"the commons": any resource—like the oceans and the water we drink—that is shared by a group of people and should be preserved for future generations

conservation: the sustainable use of natural resources

desalination: removing salt, especially from seawater

ecosystem services: benefits obtained from intact ecosystems, such as water purification, waste breakdown, and oxygen production

grey water: wastewater from showers, sinks, and washing machines (not toilets)

groundwater: fresh water that is stored under Earth's surface in aquifers, layers of sand, gravel, or porous rock; groundwater supplies springs and wells

pesticides: any substance intended to kill unwanted organisms, especially insects. They can remain in the food web and water supply, with unintended consequences.

reclaimed water: sometimes called recycled water, this is former wastewater that has been treated and purified for reuse rather than discharged into a sewer or drain.

surface water: fresh water found on Earth's surface, such as rivers, lakes, and reservoirs

sustainable: meeting current needs without losing the ability to meet future needs

virtual water: the volume of water required to produce a commodity or service

wastewater: water, including sewage, that has been used in homes, industries, or businesses and cannot be reused unless it is treated

water cycle: the continuous movement of water between the atmosphere, the land, and the sea

water ethic: the concept that humans must protect the quality and availability of water for all the species that depend on it, now and in the future

water footprint: the total volume of fresh water used to produce the foods and services consumed by an individual or community

water stress: the combination of high human population and low water supply

waterborne disease: a disease caused by microorganisms (such as protozoa, viruses, bacteria, and intestinal parasites), and which is directly transmitted by drinking contaminated water

watershed: all the land drained by a single river system. Large watersheds like the Mississippi River basin contain thousands of smaller watersheds.

wetland: shallow, often intermittently wet habitat, such as a swamp or marsh. Wetlands help filter water, absorb the force of storms and tides, and provide habitat for countless species.


Water: H2O=Life Online Educator's Guide