Glossary of Water and Wastewater Terms
A B C D E F G H I J K L M N O P Q R S T U V W Y Z5 random terms from our glossary
reuse
The use of water or wastewater after it has been discharged and then withdrawn by another user. Also see recycle.
uniformity coefficient (UC)
A measure of the degree of uniformity in a granular material such as filter media. The measure is the ratio of the diameter of a grain (particle) of a size that is barely too large to pass through a sieve that allows 60 percent of the material (by weight) to pass through to the diameter of a grain (particle) of a size that is barely too large to pass through a sieve that allows 10 percent of the material (by weight) to pass through.
uniformity coefficient = (particle diameter60%) / (particle diameter10%)
autotrophs (auto-TROFS)
Organisms (plants and some bacteria) that use inorganic materials (such as sunlight and carbon dioxide) for energy and growth.
ponding
A condition occurring on trickling filters when the hollow spaces (voids) become plugged to the extent that water passage through the filter is inadequate. Ponding may be the result of excessive slime growths, trash, or media breakdown.
sterilization (STAIR-uh-luh-ZAY-shun)
The removal or destruction of all microorganisms, including pathogens and other bacteria, vegetative forms, and spores. Also see disinfection.