TO WATER TREATMENT & ABSTRACTION
A brief glossary of terms
substance that has a pH of less than 7, which is neutral. Specifically,
an acid has more free hydrogen ions (H+) than hydroxyl ions (OH-).
water or soils contain an amount of alkali (strongly basic) substances
sufficient to raise the pH value above 7.0 and be harmful to the
growth of crops.
capacity of water for neutralizing an acid solution.
pipe, conduit, or channel designed to transport water from a remote
source, usually by gravity.
geologic formation (s) that is water bearing. A geological formation
or structure that stores and/or transmits water, such as to wells
and springs. Use of the term is usually restricted to those water-bearing
formations capable of yielding water in sufficient quantity to constitute
a usable supply for people's uses.
or rock below the land surface that is saturated with water. There
are layers of impermeable material both above and below it and it
is under pressure so that when the aquifer is penetrated by a well,
the water will rise above the top of the aquifer.
aquifer whose upper water surface (water table) is at atmospheric
pressure, and thus is able to rise and fall.
water that is under pressure when tapped by a well and is able to
rise above the level at which it is first encountered. It may or
may not flow out at ground level. The pressure in such an aquifer
commonly is called artesian pressure, and the formation containing
artesian water is an artesian aquifer or confined aquifer.
capillary action--the means by which liquid moves through the porous
spaces in a solid, such as soil, plant roots, and the capillary
blood vessels in our bodies due to the forces of adhesion, cohesion,
and surface tension. Capillary action is essential in carrying substances
and nutrients from one place to another in plants and animals.
process of water vapor in the air turning into liquid water. Water
drops on the outside of a cold glass of water are condensed water.
Condensation is the opposite process of evaporation.
desalinization--the removal of salts from saline water to provide
freshwater. This method is becoming a more popular way of providing
freshwater to populations.
volume of water that passes a given location within a given period
of time. Usually expressed in litres per second.
lowering of the ground-water surface caused by pumping.
process in which a material is worn away by a stream of liquid (water)
or air, often due to the presence of abrasive particles in the stream.
process of liquid water becoming water vapor, including vaporization
from water surfaces, land surfaces, and snow fields, but not from
overflow of water onto lands that are used or usable by man and
not normally covered by water. Floods have two essential characteristics:
The inundation of land is temporary; and the land is adjacent to
and inundated by overflow from a river, stream, lake, or ocean.
strip of relatively flat and normally dry land alongside a stream,
river, or lake that is covered by water during a flood.
well or spring that taps ground water under pressure so that water
rises without pumping. If the water rises above the surface, it
is known as a flowing well.
ground water--(1) water that flows or seeps downward and saturates
soil or rock, supplying springs and wells. The upper surface of
the saturate zone is called the water table. (2) Water stored underground
in rock crevices and in the pores of geologic materials that make
up the Earth's crust.
ground water, confined--ground water under pressure significantly greater
than atmospheric, with its upper limit the bottom of a bed with
hydraulic conductivity distinctly lower than that of the material
in which the confined water occurs.
ground-water recharge--inflow of water to a ground-water reservoir from
the surface. Infiltration of precipitation and its movement to the
water table is one form of natural recharge. Also, the volume of
water added by this process.
ground water, unconfined--water in an aquifer that has a water table that
is exposed to the atmosphere.
hardness--a water-quality indication of the concentration
of alkaline salts in water, mainly calcium and magnesium. If the
water you use is "hard" then more soap, detergent or shampoo
is necessary to raise a lather.
cyclic transfer of water vapor from the Earth's surface via evaporation
into the atmosphere, from the atmosphere via precipitation back
to earth, and through runoff into streams, rivers, and lakes, and
ultimately into the oceans.
impermeable layer--a layer of solid material, such as rock or clay,
which does not allow water to pass through.
controlled application of water for agricultural purposes through
manmade systems to supply water requirements not satisfied by rainfall.
milligram (mg)--One-thousandth of a gram.
milligrams per liter (mg/l)--a unit of the concentration of a constituent in
water or wastewater. It represents 0.001 gram of a constituent in
1 liter of water. It is approximately equal to one part per million
unit (NTU)--unit of measure for
the turbidity of water. Essentially, a measure of the cloudiness
of water as measured by a nephelometer. Turbidity is based on the
amount of light that is reflected off particles in the water.
organic matter--plant and animal residues, or substances made
by living organisms. All are based upon carbon compounds.
place where a sewer, drain, or stream discharges; the outlet or
structure through which reclaimed water or treated effluent is finally
discharged to a receiving water body.
need for molecular oxygen to meet the needs of biological and chemical
processes in water. Even though very little oxygen will dissolve
in water, it is extremely important in biological and chemical processes.
measure of the relative acidity or alkalinity of water. Water with
a pH of 7 is neutral; lower pH levels indicate increasing acidity,
while pH levels higher than 7 indicate increasingly basic solutions.
particle size--the diameter, in millimeters, of suspended sediment
or bed material. Particle-size classifications are:
 Silt—0.004-0.062 mm;
 Gravel—2.0-64.0 mm.
parts per billion--the
number of "parts" by weight of a substance per billion
parts of water. Used to measure extremely small concentrations.
parts per million--the
number of "parts" by weight of a substance per million
parts of water. This unit is commonly used to represent pollutant
disease-producing agent; usually applied to a living organism. Generally,
any viruses, bacteria, or fungi that cause disease.
maximum instantaneous discharge of a pump, stream or river at a
polychlorinated biphenyls (PCBs)--a group of synthetic, toxic industrial chemical
compounds once used in making paint and electrical transformers,
which are chemically inert and not biodegradable. PCBs were frequently
found in industrial wastes, and subsequently found their way into
surface and ground waters. As a result of their persistence, they
tend to accumulate in the environment. In terms of streams and rivers,
PCBs are drawn to sediment, to which they attach and can remain
of a quality suitable for drinking.
snow, hail, sleet, dew, and frost.
reservoir--a pond, lake, or basin, either natural or artificial,
for the storage, regulation, and control of water.
(Desalination) The process of removing salts from water using a
membrane. With reverse osmosis, the product water passes through
a fine membrane that the salts are unable to pass through, while
the salt waste (brine) is removed and disposed. This process differs
from electrodialysis, where the salts are extracted from the feedwater
by using a membrane with an electrical current to separate the ions.
The positive ions go through one membrane, while the negative ions
flow through a different membrane, leaving the end product of freshwater.
(2) (Water Quality) An advanced method of water or wastewater treatment
that relies on a semi-permeable membrane to separate waters from
pollutants. An external force is used to reverse the normal osmotic
process resulting in the solvent moving from a solution of higher
concentration to one of lower concentration.
A natural stream of water of considerable volume, larger than a
brook or creek.
(1) That part of the precipitation, snow melt, or irrigation water
that appears in uncontrolled surface streams, rivers, drains or
sewers. Runoff may be classified according to speed of appearance
after rainfall or melting snow as direct runoff or base runoff,
and according to source as surface runoff, storm interflow, or ground-water
runoff. (2) The total discharge described in (1), above, during
a specified period of time. (3) Also defined as the depth to which
a drainage area would be covered if all of the runoff for a given
period of time were uniformly distributed over it.
saline water--water that contains significant amounts of dissolved
Here are example parameters for saline water:
water - Less than 1,000 parts per million (ppm)
water - From 1,000 ppm to 3,000 ppm
Moderately saline water
- From 3,000 ppm to 10,000 ppm
Highly saline water - From 10,000
ppm to 35,000 ppm
applied to material in suspension in water or recently deposited
from suspension. In the plural the word is applied to all kinds
of deposits from the waters of streams, lakes, or seas.
formed of sediment, and specifically: (1) sandstone and shale, formed
of fragments of other rock transported from their sources and deposited
in water; and (2) rocks formed by or from secretions of organisms,
such as most limestone. Many sedimentary rocks show distinct layering,
which is the result of different types of sediment being deposited
tanks in which floating wastes are skimmed off and settled solids
are removed for disposal.
The slow movement of water through small cracks, pores, Interstices,
etc., of a material into or out of a body of surface or subsurface
water. (2) The loss of water by infiltration into the soil from
a canal, ditches, laterals, watercourse, reservoir, storage facilities,
or other body of water, or from a field.
substance that dissolves other substances, thus forming a solution.
Water dissolves more substances than any other, and is known as
the "universal solvent".
general term for a body of flowing water; natural water course containing
water at least part of the year. In hydrology, it is generally applied
to the water flowing in a natural channel as distinct from a canal.
that is on the Earth's surface, such as in a stream, river, lake,
fine soil particles that remain in suspension in water for a considerable
period of time without contact with the bottom. Such material remains
in suspension due to the upward components of turbulence and currents
and/or by suspension.
that are not in true solution and that can be removed by filtration.
Such suspended solids usually contribute directly to turbidity.
Defined in waste management, these are small particles of solid
pollutants that resist separation by conventional methods.
transpiration--process by which water that is absorbed by plants,
usually through the roots, is evaporated into the atmosphere from
the plant surface, such as leaf pores.
smaller river or stream that flows into a larger river or stream.
Usually, a number of smaller tributaries merge to form a river.
amount of solid particles that are suspended in water and that cause
light rays shining through the water to scatter. Thus, turbidity
makes the water cloudy or even opaque in extreme cases. Turbidity
is measured in nephelometric turbidity units (NTU).
wastewater--water that has been used in homes, industries,
and businesses that is not for reuse unless it is treated.
the circuit of water movement from the oceans to the atmosphere
and to the Earth and return to the atmosphere through various stages
or processes such as precipitation, interception, runoff, infiltration,
percolation, storage, evaporation, and transportation.
term used to describe the chemical, physical, and biological characteristics
of water, usually in respect to its suitability for a particular
top of the water surface in the saturated part of an aquifer.
artificial excavation put down by any method for the purposes of
withdrawing water from the underground aquifers. A bored, drilled,
or driven shaft, or a dug hole whose depth is greater than the largest
surface dimension and whose purpose is to reach underground water
supplies or oil, or to store or bury fluids below ground.