Introduction to Desalination. Louis Theodore

sewer – A piping system employed exclusively for the transport of stormwater from streets, buildings, and surface runoff.

       Stormwater runoff – The portion of the volume of a rainfall event that exceeds the infiltration and storage capacity of a watershed.

       Subterranean water – The water that occurs in open spaces within rock materials of the Earth’s crust.

       Superheated steam – Steam at a temperature above its boiling point at a given pressure.

       Supersaturation – An unstable condition in which a solvent contains more dissolved matter or gas than is present in a saturated solution of the same components at an equivalent temperature.

       Surface water – All water that is above the surface of the ground and is naturally open to the atmosphere.

       Surge irrigation – The intermittent application of water to irrigation pathways; this method pulses water down the furrow and creates more uniform irrigation water distribution.

       Suspension – A system in which very small particles are uniformly dispersed in a liquid or gaseous medium.

       Tank – A stationary device that is essentially a container, e.g. designed to contain an accumulation of waste or liquid, that is constructed primarily of non-earthen materials which provide structural support.

       Temperature gradient – The change in temperature with distance or position.

       Tertiary treatment – The advanced treatment of wastewater beyond secondary treatment; it may involve combinations of physical, chemical, and biological treatment processes to remove solids, nutrients, metals, salts, nonbiodegradable organics, etc. to prepare the waste for disposal into highly sensitive environments or for reuse.

       Thickener – A small circular or rectangular sedimentation tank, designed to increase the concentration of solids in a suspension.

       Thickening agent – Any of a variety of substances employed to increase the viscosity of liquid mixtures and solutions without changing its other properties.

       Tidal wave – An exceptionally large wave, tsunami, or increase in the water level along a shore due to strong winds, volcanic eruption, or earthquake.

       Tide – The periodic rising and falling of water that results from the gravitational attraction of the moon and sun acting on the rotating Earth.

       Total organic carbon (TOC) – The total amount of organic carbon present in water as organic compounds (e.g. amino acids, hydrocarbons, proteins, etc.).

       Toilet displacement device – Object placed in a toilet tank to reduce the amount of water used per flush; for example, weighted plastic jugs filled with water or toilet dams that hold back a reservoir of water when the toilet is flushing.

       Toxic – A term used to describe a poisonous substance that has a harmful effect on an organism by ingestion, inhalation, or skin absorption.

       Trace – A very small quantity of a constituent, the amount of which cannot be determined precisely because of its low concentration.

       Transpiration – The process by which water passes through living organisms, primarily plants, and into the atmosphere.

       Treatment – Any method, technique, or process that is designed to change the physical, chemical, and/or biological composition of a waste so as to neutralize it, recover energy or material resources from it, render it nonhazardous or less hazardous, or make it safer to transport, store, reuse, or dispose of.

       Tributary – A stream or river that flows into a larger stream or main stem (or parent) river or a lake.

       Trough – A structure employed to hold or transport fluids.

       Tsunami – A sea wave caused by an underwater seismic disturbance such as sudden faulting, a landslide, or volcanic activity.

       Turbid water – Water that is cloudy due to fine particles in suspension.

       Turbidity – A measure of the fine particles suspended in a fluid; measured as the proportion of light passed through a sample that is refracted by suspended particles in a water column.

       Ultrafiltration – The separation of a solute with a specific molecular size and shape from a solution by applying pressure to force the solvent to flow through a membrane.

       Underground sources of drinking water – The aquifers that are currently being employed as a source of drinking water, and those that are capable of supplying a public water system.

       Unconfined aquifer – An aquifer whose upper surface is free of a confining layer and thus is able to fluctuate under atmospheric pressure.

       Upstream – The regions of a river system located in the direction opposite to the flow of a stream from a given position; a section of a river system that is hydraulically higher, if gravity transports the water away from the given location.

       Uptake – The act of taking up, drawing up, or absorbing.

       Urban runoff – The storm water from city streets and adjacent domestic or commercial properties.

       Utility – Public water service provider.

       Vapor pressure – The pressure exerted by a vapor in equilibrium with a liquid at a given temperature.

       Virgin material – A raw, unused material.

       Wake – The visible trail of turbulence left behind a moving stream.

       Wash solvent – A liquid added to a liquid–liquid extraction to wash or enrich the purity of the solute used in the extraction process.

       Wash water – The water employed to wash equipment.

       Wastewater – The water used to carry liquid waste material, consisting of dissolved and suspended solids, organics, and nutrients from homes, businesses, institutions, and industries to wastewater treatment plants for contaminant removal prior to release to surface water.

       Wastewater operations and maintenance – The actions taken after construction of wastewater treatment facilities to assure that the facilities will be properly operated and maintained.

       Wastewater treatment – A series of processes in which wastewater is treated in order to remove or alter its objectional constituents to a degree that renders it less harmful or dangerous.

       Wastewater treatment plant – A series of unit operations including screening, sedimentation, digestion, stabilization, dewatering, disinfection, and other processes for removing pollutants from wastewater before it discharges into the environment.

       Wastewater treatment unit – A device that is part of a wastewater treatment facility which is subject to regulation.

       Water – A colorless, odorless, tasteless liquid composed of the elements hydrogen and oxygen.

       Water audit – Program involving sending trained water auditors to participating family homes, free of charge, to identify water conservation opportunities such as repairing leaks and installing low-flow plumbing and to recommend changes in water use practices to reduce home water use.

       Water conditioning – The treatments, excluding disinfection, that are intended to produce a water which is free of taste, odor, and undesirable contaminants.

       Water conservation – Activities designed to reduce the demand for water, improve efficiency of use, and reduce losses and waste of water in a potable water system.

       Water consumption – The quantity of water supplied in a municipality or district for a variety of uses during a given period.

       Water main – The water pipe, located in the street, from which domestic water supply is delivered to specific premises.

       Water