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Youth Activities: Water Resources


This glossary was developed to accompany the Youth Activities: Water Resources.

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Aeration:  The process of bubbling air through water or wastewater to remove impurities.

Aquifer:  Areas underground where groundwater exists in sufficient quantities to supply wells or springs.

Coagulation:  A clumping of particles in water and wastewater to settle out impurities; it is often induced by chemicals such as lime, alum, and iron salts.

Condensation:  The process by which a vapor becomes a liquid.

Contamination (Water):  The adding of any substance to water which makes it unfit for use.

Disinfection:  A process whereby most microorganisms in or on a substance are killed; there is A high probability that pathogenic (disease causing) bacteria are killed in the process but depending on the process, destruction of viruses is not as certain.

Distillation:  The separation of different substances in a solution by boiling off those of low boiling point first.  For example, water can be distilled and the steam condensed back into a liquid that is almost pure water.  The impurities (minerals) remain in the concentrated residue.

Diatomaceous Earth:  An earthy deposit formed mainly of diatoms (one-celled marine life forms) that are pulverized and resemble sandy flour.

Erosion:  The wearing away of the land surface by wind, water, ice, or other geologic agents.  Erosion occurs naturally from weather or runoff but is often intensified by human land use practices.

Evaporation:  The process by which water becomes a vapor usually through the application of heat energy.

Filtration:  A mechanical process which involves moving water through a material, usually sand, designed to catch and remove particles.

Floc:  The large particles formed in water and wastewater treatment processes when small particles begin to coalesce.

Floculation:  The formation of floc in the water and wastewater treatment process.

Groundwater:  Water found under the ground, in aquifers and between soil particles.

Groundwater Recharge:  Water that moves below the root zone as "deep percolation" and eventually joins the groundwater.

Hard Water:  Water containing excessive amounts of calcium and magnesium ions which prevents soap from lathering and produces scale and incrustation.

Hydrologic Cycle (Water Cycle):  The cycle of water movement from the atmosphere to the earth and back to the atmosphere through condensation, precipitation, evaporation, and transpiration.

Infiltration:  The gradual downward flow of water from the surface into the soil.

Irrigation:  The controlled application of water for agricultural purposes through human-made systems to supply water requirements for crops not satisfied by rainfall.

Leaching:  The process by which soluble materials in the soil, such as nutrients, pesticide chemicals, or contaminants, are washed into a lower layer of soil or are dissolved and carried away by water.

Nonpoint Source (NPS) Pollution:  Forms of pollution caused by sediment, organic and inorganic chemicals, and biological, radiological, and other toxic substances originating from land use activities, which are carried to lakes and streams by surface runoff.  Nonpoint source pollution occurs when the rate of materials entering these waterbodies exceeds natural levels.

Percolation:  The movement of water through the subsurface soil layers, usually continuing downward to groundwater.

Pollutant:  Anything which alters the physical, chemical, or biological properties of water making it harmful or undesirable for use.

Precipitation:  Water received on Earth directly from clouds as rain, hail, sleet, or snow.

Runoff:  Precipitation that flows overland to surface waters, such as streams, rivers, and lakes.

Sedimentation:  The removal, transport, and deposition of detached soil particles by flowing water or wind.  Also, the process of solid particles settling out of water and wastewater treatment processes.

Soft Water:  Any water that is not "hard," i.e., does not contain a significant amount of dissolved minerals such as salts containing calcium or magnesium.

Soil Profile:  A vertical section of the Earth's highly weathered upper surface often showing several distinct layers or horizons.

Stream:  A general term for a body of flowing water.  In hydrology, the term is generally applied to the water flowing in a natural channel as distinct from a canal.  More generally, it is applied to the water flowing in any channel, natural, or artificial.

Surface Water:  All water on the surface of the Earth including lakes, ponds, rivers, oceans, streams, puddles, and runoff.

Transpiration:  The process by which water vapor escapes from the living plant, principally the leaves, and enters the atmosphere.

Wastewater Treatment Plant:  A facility that receives wastewater (and sometimes runoff) from domestic and/or industrial sources, and by a combination of physical, chemical, and biological processes reduces (treats) the wastewater to less harmful byproducts; also known by the acronyms WWTP, STP (sewage treatment plant), and POTW (publicly owned treatment works).

Water Table:  The upper surface of the zone of saturation; the upper surface of the groundwater.

Watershed:  The land area from which surface water and runoff drains into a stream, channel, lake, reservoir, or other body of water; also called a drainage basin.

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Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture, James A. Christenson, Director, Cooperative Extension, College of Agriculture, The University of Arizona. The University of Arizona College of Agriculture is an Equal Opportunity employer, authorized to provide research, educational information, and other services only to individuals and institutions that function without regard to sex, race, religion, color, national origin, age, Viet Nam Era Veteran's status, or disability.

For problems or questions regarding this web contact Dr. Kitt Farrell-Poe.
This document was last modified: 04-Sep-2001 .