ACRE-FOOT: The volume of water that would cover a 1-acre area 1 foot deep. Equivalent to approximately 1233.6 cubic meters or 325,900 gallons.

AGGRESSIVE WATER: Water having corrosive qualities.

ANION: A negatively charged ion that migrates to the anode when an electrical potential is applied to a solution.

BRACKISH WATER: Water containing low concentration of soluble salts, usually between 1,000 and 10,000 mg/L.

BRINE: Water saturated with, or containing a high concentration of salts, usually in excess of 36,000 mg/L.

BRINE CONCENTRATOR: Term used to describe a vertical tube falling film evaporator employing special scale control techniques to maximize concentration of dissolved solids.

CATION: A positively charged ion that migrates to the cathode when an electrical potential is applied to a solution.

COGENERATION: A power system that simultaneously produces both electrical and thermal energy from the same source.

CONDENSATE: Water obtained by evaporation and subsequent condensation.

DBOOT: Design-Build-Own-Operate-Transfer

DEIONIZATION: (DI) The process of removing ions from water, most commonly through an ion exchange process.

ELECTRODEIONIZATION: (EDI) A water treatment process combining an electrodialysis membrane process with an ion exchange resin process to produce high purity, demineralized water.

FORWARD OSMOSIS: (FO)Like reverse osmosis, forward osmosis is an osmotic process that uses a semi-permeable membrane to separate water from dissolved solutes. Whereas RO uses pressure to effect the separation, forward osmosis uses an osmotic pressure gradient, such as a draw solution, to induce the flow of water through the membrane.

INDIRECT REUSE: The beneficial use of reclaimed water after releasing it for storage or dilution into natural surface waters or groundwater.

MAKEUP WATER: Fluid introduced in a recirculating stream to maintain an equilibrium of temperature, solids concentration or other parameter(s).

ULTRAPURE WATER: Water with a specific resistance higher than 1 megohm-cm.

 Source: International Desalination Association and Water Desalination Report (www.idadesal.org).