Water Facts: Water Definitions

Terms & Definitions

Aqueduct - Man-made canal or pipeline used to transport water

Aquifer - An underground geologic formation of rock, soil, or sediment that is naturally saturated with water; an aquifer stores groundwater

Bond - A promise to repay money borrowed, plus interest, over a specific period of time

Bond Issue - A means of raising large amounts of money for major projects by selling bonds

Chlorination - The treatment of a substance, such as drinking water, with chlorine in order to kill disease-causing organisms

Confined Aquifer - An aquifer that is bound above and below by dense layers of rock and contains water under pressure

Conjunctive Use - Storing imported water in a local aquifer, in conjunction with groundwater, for later retrieval and use

Desalination - The process of removing salt from seawater or brackish water

Floodplain - Area formed by fine sediments spreading out in the drainage basin on either side of the channel of a river as a result of the river's fluctuating water volume and velocity

Groundwater - Water that has percolated into natural, underground aquifers; water in the ground, not water puddle on the ground

Groundwater Recharge or Replenishment - Pumping or percolating storm water runoff or imported water into an aquifer to replenish its supplies

Hydroelectric Plant - A power plant that produces electricity from the power of rushing water turning turbine-generators

Hydrology - The scientific study of the behavior of water in the atmosphere, on Earth's surface and underground

Irrigation - Supplying water to agriculture by artificial means, such as pumping water onto crops in an area where rainfall is insufficient

Recharge - Replenishing an aquifer with stormwater or imported water

Reclaimed Water - Wastewater that has been cleaned so that it can by reused for most purposes except drinking Source Water - The supply of water for a water utility. Source water is usually treated before distribution to consumers, but some groundwaters are of such a quality that they can be distributed untreated.

Supplemental Water - An additional source of water to replace the pumped water rights.

Surface Runoff - Water flowing along the ground into rivers, lakes, and oceans

Surface Water - All water, fresh and salty, on the Earth's surface

Unconfined Aquifer - An aquifer that discharges and recharges with an upper surface that is the water table

Water Quality Equivalents - Scientific testing has become more and more precise over time so that today the presence of one thing in another can be measured in previously unheard of amounts. Consider these examples of what certain detections mean in alternative situations:

• 1 part per million (ppm) = 1 millogram per liter
  1 second in 11 ½ days
  1 inch in 15.8 miles
  1 eye drop in 13 gallons

• 1 part per billion (ppb) = 1 microgram per liter
  1 second in 31.7 years
  1 inch in 15,800 miles
  1 eye drop in 13,000 gallons

• 1 part per trillion (ppt) = 1 nanogram per liter
  1 second per 31,700 years
  1 inch in 15,800,000 miles
  10 eye drops in Rose Bowl (13 million gallons)

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