Water Quality
Glossary
of Water Quality Terms
Words within the definitions which are bold are themselves defined
in the glossary.
A
Absorption
The
incorporation of a substance into the body of another, (see sorption,
adsorption).
Accuracy
This is an indicator of how close a measured
value comes to the actual or true value (see precision).
Acid
A compound resulting in a pH less
than 7 when in aqueous solution, a molecule that can give
up
a proton to a base, accept an unshared pair of electrons from
a base or react
with a base to form
a salt, a substance that has more free hydrogen ions,
H+, than hydroxyl ions,
OH-, (see alkaline).
Acidity
Having the properties of an acid;
a pH less than
7.
Activated
carbon
Pure carbon heated to promote active sites which
can adsorb pollutants, used in some water
treatment systems to remove certain
organic chemicals and radon gas.
Acute toxicity
As commonly used it is a pronounced effect,
severe biological harm or death, produced in an
organism by a toxicant, a substance
or a mixture of substances within a short period of time, usually
96 hours or less, after exposure. The strict implication is simply one of rapid
onset
of
effects, in comparison with the life span of the organism; severity is not
necessarily implied. For
algae and bacteria 96 hours would be a chronic exposure
since it would last for several
generations.
Adhesion
The molecular attraction exerted between
the surfaces of materials in contact, (see cohesion).
Adsorbable
organic halides, AOX
The total
of all halogenated organic compounds, particularly
that are fluoridated,
chlorinated or brominated, (see adsorption,
halides).
Adsorption
The attachment or adhesion of a substance or chemicals generally
on the surface of another
solid material, adsorption is often
used to extract pollutants by causing them to be attached
to
materials such as activated
carbon, (see sorption).
Aeration
The addition, by bubbling, mixing or turbulent exposure, of air
or oxygen into water, or by
spraying the water into the air,
increasing the dissolved oxygen concentration in the water
and
dissipating or stripping volatile contaminants and other
pollutants from the water into the air.
Aerobic
The presence of gaseous or dissolved oxygen,
the presence of or utilizing oxygen, (see
anaerobic).
Aesthetic
Pleasing or acceptable to the senses, primarily taste, odor and
vision.
Algae
A group of chlorophyll-containing,
non-flowering plants, mostly
aquatic, although many are
planktonic,
some species are extremely large.
Algal bloom
A bloom of algae occurs
when their growth is so rapid that they become numerous enough to
colour a body
of water, a population explosion of phytoplankton in response
to changing
environmental conditions, including eutrophication from wastewater and non-point sources,
blooms can result
in oxygen depletion and biological impacts such as fish kills,
blooms are often
the result of urban runoff of lawn fertilizers.
Alkaline
Having a pH greater than 7, the measurement of constituents in
a water supply which determine
alkaline conditions, the alkalinity of water is a measure of its capacity to neutralize acids.
Alkalinity
The measurement of chemicals in a water supply which determine
alkaline conditions, the
alkalinity of water is a measure
of its capacity to neutralize acids.
Alluvial
Refers to particles carried by running water which are deposited
when the flow rate decreases.
Alum
An aluminum sulphate salt, generally potassium or ammonium is
the cation, used to coagulate particles in water
treatment.
Amphipoda
An Order of Crustacea which
includes shrimp, these numerous small, but generally visible,
flea-like organisms which are laterally
flattened, are abundant in marine environments.
Ambient
Refers to natural background conditions in the surrounding environment
outside the zone in which water quality may be influenced
by a discharge or source of contamination.
Anadromous
Ascending from the sea to fresh
water for spawning at certain seasons.
Anaerobe
An organism that can only exist in the absence or near-absence
of gaseous or dissolved oxygen.
Anaerobic
Denotes absence of gaseous or dissolved oxygen, submerged sediments below a narrow oxygenated layer may be anaerobic, also refers
to metabolic activities, glycolysis, in the absence of oxygen
which occurs in some microorganisms.
Anion
A negatively charged ion.
Annelids
A phylum of segmented marine and freshwater worms,
distinguished from non-segmented roundworms
and flatworms, (see worms,
polychaetes and oligochaetes).
Anoxia
Absence of oxygen, (see anaerobic,
hypoxia).
Anthropogenic
Having to do with the activities of man as opposed to those of
nature, man-made, -modified or
-influenced.
AOX, Adsorbable
organic halides
The total of all halogenated
organic compounds particularly
those that are fluoridated, chlorinated or brominated, (see
adsorption, halides).
Aquatic
Living and growing in or on and
generally requiring water, (see
freshwater, marine, brackish).
Aqueous
Water based; an aqueous
solution is a solution where water is
the solvent.
Aquifer
Water within the soil or
rocks beneath the surface of the earth that supplies wells and
springs, water in the zone
of saturation where all openings
in rocks and soil are filled with water, the
upper surface of which forms
the water table, the streams or
pools of water that flow or collect under
the surface of the land and not on the surface, these may be
confined if there are
layers of impermeable material
both above and below 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,
or unconfined when the upper
water surface, the water table, is at atmospheric
pressure, and is able to rise and fall,
any geological formation containing
or transmitting water, especially one that supplies the water
for wells and
springs, use of the term may be restricted to those water-bearing
formations capable of yielding
water in sufficient quantity to constitute a usable supply, (see
surfacewater,
ground water).
Arithmetic
mean
The average of the sum of all
the observations, (see geometric
mean).
Artificial
recharge
The process where water is
put into ground water, or aquifer,
storage from surface water supplies
such as irrigation water, reclaimed wastewater
or induced infiltration from streams
or wells.
Aromatic
A general term that includes the organic compounds containing
at least one benzene ring.
Assimilative
capacity
The amount
of pollution a water body can receive without
noticeable degradation, as a result of the
natural ability of the water and its associated chemical
and biological systems to dilute or transform contaminants.
Atmospheric
deposition
The contribution
of atmospheric pollutants or chemical constituents to land
or water
ecosystems, deposition results from materials
in rain or snowfall, combined with dry dust fallout,
atmospheric sources
are a significant source of nutrients and contaminant to aquatic
systems.
Return to the Index
B
Backwashing
Reversing the flow of water through a water
treatment filter or membrane to clean and remove
deposits.
Bacteria
Small unicellular organisms lacking a nucleus and some other
eukaryotic organelles, they
may have photosynthetic pigments
but lack chloroplasts, the specialized photosynthetic
organelles in higher plants, and mitochondria.
Base
A compound resulting in a pH greater than 7
when in aqueous
solution,
a molecule that can
accept a proton from an acid,
donate an unshared pair of electrons to an acid or
react with an
acid to form a salt,
a substance that has fewer free hydrogen
ions, H+, than hydroxyl ions,
OH-, (see alkaline).
Base flow
The volume of flow in a stream or river during dry conditions,
as opposed to conditions
influenced by storm runoff.
Bay
A relatively small body of
water partially isolated from the main portion of the sea, ocean or lake by
a relatively narrow opening or channel.
Beneficial
use
Water used for an anthropogenically accepted purpose such as
domestic and municipal water supply, industry, irrigation,
mining, hydroelectric power, navigation, recreation, livestock
raising, aesthetics, aquatic life and wildlife, (see contact
recreation, non-contact
recreation).
Benthic
Associated with the sediments on the bottom of a water body
Benthic
organism
Any organism that lives in or near the bottom of a water body
or in the sediment.
Benthos
The organisms that live in or near the bottom of a water body
or in the sediment.
Benzene
An organic compound, a ring molecule of six carbons and six hydrogens
with three shared or
resonant double carbon-to-carbon bonds,
known as an aromatic compound.
Bioaccumulation
The uptake, retention and concentration above background levels
of environmental substances
by an organism from its environment
and food, (see biomagnification).
Bioassay
The quantitative estimation of biologically active substances
by the amount of their actions
under standardized conditions
on or in living organisms; often linked, unnecessarily, with
drug testing; some people prefer to simply use toxicity
test.
Biochemical
oxygen demand, BOD
A measure of the amount of dissolved oxygen required
to completely
oxidize the available organic wastes,
a quantitative measure of
the degree to which organic compounds consume
oxygen in water, based on a five-day test in which loss of oxygen
in a sample results
from bacterial respiration and chemical processes, a traditional
water quality measurement applied to wastewater such as treated
sewage.
Bioconcentration
The increase of a substance or contaminant in
a food web such that the organisms eventually contain
higher concentrations of the
substance than their food sources, the magnification of contaminant
concentrations in organisms due to increased
tissue concentrations at each successive trophic level
in a food chain, generally, but not always,
occurs due to a
contaminant being soluble in fatty tissues and
not in water. (see bioaccumulation, biomagnification).
Biomagnification
The increase of a substance
or contaminant in a food web such
that the organisms eventually contain
higher concentrations of
the substance than their food sources, the magnification
of contaminant
concentration in organisms due to increased
tissue concentrations at each successive trophic level
in a food chain, generally, but not always,
occurs due to a
contaminant being
soluble in fatty tissues and not in water,
(see bioaccumulation, bioconcentration).
Biomass
The total amount of biological material present at any given
time or over a defined time period, (see productivity, standing
crop).
Biosolids
A nutrient-rich organic material resulting from the treatment
of wastewater which contains nitrogen and phosphorus along
with smaller amounts of other nutrients, such as potassium,
sulfur, magnesium, calcium, copper and zinc, soil that is
lacking in these substances can be fertilized with biosolids which also improve soil properties and plant productivity reducing dependence on inorganic fertilizers.
Biota
All living organisms including bacteria, plants and animals.
Bioturbation
The disturbance of sediments due to displacement by organisms,
bioturbation resulting from burrowing of organisms in the
benthic habitat increases sediment
aeration and influences
contaminant equilibria with the overlying water.
Blackwater
Wastewater from toilets, latrines, privies, water containing
feces or body fluids and water from sinks used for food preparation
or disposal of chemical or biological ingredients, (see greywater).
Blue-green
algae
Prokaryotic organisms with a bacteria-like cell structure,
lacking a nucleus and other organelles, these species manufacture
photosynthetic pigments but lack chloroplasts, the specialized
photosynthetic organelles in higher plants, in some situations
an increase in
blue-green algae can indicate an environmental
stress such as pollution.
BOD, Biochemical
oxygen demand
A measure of the amount of dissolved oxygen
required to completely
oxidize the available organic wastes,
a quantitative measure
of the degree to which organic compounds consume
oxygen in water, based on a five-day test in which loss of
oxygen in
a sample results from bacterial respiration and chemical processes,
a traditional water quality measurement applied to wastewater such as treated sewage.
Bog
A wetland that is perched above the watertable and has no direct
hydraulic connection to it, bogs accumulate peat and the
vegetation is dominated by sphagnum moss.
Brackish
Water that is
neither fresh water nor marine but a mixture of the two or intermediate
in salinity, usually found in estuaries where the amount
of salinity is constantly fluctuating.
Brine
Highly salty and heavily mineralized
water containing heavy metal and organic contaminants.
Brominated
A compound that has been
reacted with the halide bromine and now contains at least one
bromine atom in the molecule.
Buffer
A compound or solution capable of resisting a change in pH.
Return to the Index
C
Carcinogen
A substance capable of causing cancer.
Cation
A positively charged ion.
CFS,
Cubic feet per second
A quantitative measure of the flow, in streams and rivers,
it is equal to a volume of water one foot high and one foot
wide flowing a distance of one foot in one second, one cfs is equal to 7.48 gallons of water per second.
CFU,
Colony forming units
A quantitative measure of the concentration of bacteria in a water sample, bacterial colonies on laboratory media resulting from filtering and culturing
bacteria from a water sample, each colony in the laboratory
culture is presumed to have arisen from the multiplication
of a single bacterium in the original sample.
Chlorinated
A compound that has been
reacted with the halide chlorine and now contains at least one
chlorine atom in the molecule.
Chlorination
The addition of chlorine
to water primarily for the purpose of disinfection but also for
other
biological or chemical purposes.
Chlorophenols
Broad spectrum pesticides produced when phenol rings have a number
of chlorine atoms attached, formerly used in cut lumber treatment
to prevent discolouration by fungus, often associated with
pulpmill effluent and wood preservatives.
Chlorophyll
The coloured pigments, often green, red or brown, found in plants
and algae which trap and convert light energy to chemically
stored energy which is then used to create organic molecules
from inorganic raw materials.
Chlorphyll-a
The primary green-coloured pigment found in plants and algae which traps and converts light energy to chemically stored
energy which is then used to create organic molecules from
inorganic raw materials.
Chloroplasts
The organelles,
in eukaryotic cells that carry out photosynthesis,
where the chlorophyll pigments
and related enzymes are located, specialized structures that
carry out photosynthesis in
plants and algae.
Chromosomes
The structures in the nucleus
of a eukaryotic cell which carries the DNA or
genetic material in
genes.
Chronic
toxicity
A long-term
toxic effect produced in an organism by a toxicant, a substance
or a mixture of
substances.
Cilia
Many
short fine hairs on the cell surface which are used for locomotion
or food gathering in many
microscopic organisms and their larvae.
Ciliate
Having many cilia on the
surface which are used for locomotion or food gathering.
Coagulation
The use of chemicals to make suspended
solids clump together into larger aggregates, flocs, for easier filtration or sedimentation,
coagulation in water treatment uses alum to
congregate solids in the water into
a mass that can be readily trapped by a filter, (see flocculation).
Cohesion
The molecular attraction
by which the particles of a body are united throughout the mass,
whether like or unlike, (see adhesion).
Coliform
Non-pathogenic natural gut bacteria monitored
when testing water to indicate the possible
presence of pathogenic bacteria.
Colloids
Finely divided solids which will not settle out
by gravity alone but which may be removed by
coagulation or biochemical action.
Colony
forming units, CFU
A quantitative measure of the concentration of bacteria in
a water sample, bacterial colonies on laboratory media resulting
from filtering and culturing bacteria from a water sample,
each colony in the laboratory culture is presumed to have arisen
from the multiplication of a single bacterium in the original
sample.
Combined
sewer
A sewer system that carries both sanitary
sewage and stormwater
runoff, when sewers are constructed this way, wastewater treatment
plants have to be sized to handle stormwater flows and often
some of the water receives little or no treatment during overflows
or bypasses during extreme storm events, (see separate
sewer).
Combined
sewer overflow
A point in a sewer collection
system where
domestic sewage mixed in varying proportions with
stormwater overflows to a receiving water
body.
Composite
sample
A series of samples taken
over space and/or time to determine the average condition of
an area
or a time period, (see grab sample).
Concentration
Quantitative amount of a solute, chemical or pollutant in a specified
volume or weight of solvent, air, water, soil or other medium,
accumulating a level of some material over and above the
level found in the ambient environment, generally applied
to an organism.
Condensation
The change of state from
a gas to a liquid, (see evaporation, sublimation, vapourization,
transpiration, evapotranspiration).
Consumptive
use
The quantity
of water not available for reuse since it is incorporated into
a product or in some way at
least temporarily removed from the water cycle,
evapotranspiration, evaporation,
incorporation into plant tissue,
infiltration into ground water
and consumption by humans, wildlife
or livestock, are some of the reasons water may not be immediately
available for reuse. (see
non-consumptive use).
Contact
recreation
Activities involving a
significant risk of ingestion of water, such as wading by children,
swimming, water skiing, diving and surfing, human activity
involving bodily contact with water and therefore the potential
for increased risk to health when contaminants or pathogens are present, (see non-contact
recreation).
Contaminant
A substance that causes harm by contact or association, sewage or other materials that will
render water
unfit for its intended use, anything added to a substance that
makes the substance
impure or unfit for its intended use, (see
pollutant).
Contamination
Introducing a substance into
water that causes harm by contact or association, the introduction
into water of sewage or other materials that will render the
water unfit for its intended use, (see pollution).
Copepoda
Subclass of Crustacea, small
aquatic invertebrates that are food for fish, free living forms
are common in benthic and planktonic
samples, some species are
parasitic.
Crustacean
A class of segmented Arthropod
organisms with an exoskeleton, a pair of appendages on each segment
and two pairs of antennae, includes crabs, lobsters, crayfish,
shrimp, wood lice, barnacles and water fleas or Daphnia.
Cubic
feet per second, CFS
A quantitative measure of the flow, in streams and rivers,
it is equal to a volume of water one foot high and one foot
wide flowing a distance of one foot in one second, one cfs is equal to 7.48 gallons of water per second.
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D
Deionized
water
Water free of inorganic chemicals
Delta
An alluvial deposit consisting
of rock particles, sediment and debris, dropped by a stream or
river as it enters another body of water, the fan-shaped deposit
where a river discharges to a larger, slower moving water body,
important for wetland habitat values.
Denitrification
The natural chemical conversion
of dissolved nitrite nitrogen to nitrate and
finally to gaseous
nitrogen, removing it from the aquatic system.
Desalination
The process of salt removal
from sea or brackish water, the removal of salts from saline water to provide fresh
water, an increasingly popular way of
providing fresh water to coastal populations.
Designated
water use
A water use that
is to be protected at a specific location for such purposes
as use by aquatic
life or wildlife, for irrigation or
stock
watering, in industrial activities, for recreation or as
drinking water, (see contact
recreation,
non-contact recreation).
Detection
limit
The lowest concentration of
a substance in
water that can be reproducibly determined by a
specific analytical procedure or test method.
Diatom
A group
of phytoplankton species utilizing silica as a
structural component of the cell wall, a dominant
component of the plankton population in many areas.
Diffuser
A structure composed of perforated pipes,
placed at the end of an outfall pipe, which is
designed to spread the effluent widely so
as to facilitate dilution.
Dilution
The process of mixing a liquid,
usually water, that has a lower concentration of a substance
or pollutant with effluent containing the substance or pollutant,
or the pollutant or substance itself, such that the final concentration after mixing is lower than that in the effluent or of the pure
substance.
Dinoflagellate
A unicellular, generally motile species of planktonic
algae with
two whip-like flagella arranged in a characteristic pattern,
this group includes some common plankton species and also
red tide organisms such as Gonyaulax
monilata and Ptychodiscus
brevis.
Dioxins
Toxic organic compounds containing
a specific complex aromatic ring structure and
containing at least one chlorine atom in
the molecule, (see furans).
Diploid
The condition when there are two complimentary sets of chromosomes in a cell which occurs after fertilization and remains so
until the cell undergoes meiosis to form haploid
eggs and
sperm.
Discharge
The release of water which
may or may not contain waste into the environment, often via
a pipe or ditch into a stream, the volume of water that passes
a given point within a given period of time, an all-inclusive
outflow term, describing a variety of flows such as from a pipe
to a stream or from a stream to a lake or ocean, usually expressed
in cubic feet per second.
Disinfectant
A chemical usually an oxidant,
such as chlorine, chloramine, ozone, hydrogen peroxide or potassium
permanganate, or radiation, such as ultraviolet light or ionizing
radiation which destroys pathogens in water, a substance or action
used to purify a medium and kill or inactivate infectious organisms,
chlorine is currently the most common disinfectant used with
water.
Disinfection
The process of destroying
microorganisms in water by the application of a disinfectant,
killing most of the harmful and objectionable bacteria in sewage or drinking
water usually accomplished by introduction of chlorine
or exposure to ultraviolet radiation which sterilizes the bacteria.
Disinfection
byproducts
Chlorinated organic chemicals, including trihalomethanes, are
formed when water containing organic materials is disinfected with chlorine, these compounds are toxic, the formation of
these compounds can be minimized by filtering or otherwise
removing the organic compounds before chlorination.
Dispersion
The movement and spreading of contaminants from
the point of introduction in an aquifer or
surface water body.
Dissolve
The process by which solid particles separate from the mass and
mix molecule by molecule with a liquid and appear to become
part of the liquid.
Dissolved
Separated into individual
atoms or molecules and dispersed in a liquid like water.
Dissolved
metals
In a liquid, metals which pass through a
filter of a designated pore size, are assumed for environmental purposes to be
dissolved.
Dissolved
organic matter, DOM
Carbon compounds in water
solution, generally from the decomposition of natural plant
and animal tissues, but including some anthropogenic
contaminants.
Dissolved
oxygen, DO
The amount of oxygen gas dissolved in a given quantity of water
at a given temperature and atmospheric pressure, usually expressed
as a concentration in parts per million, ppm, or as a percentage
of saturation.
Dissolved
oxygen deficit, DO deficit
The difference between the oxygen saturation value in water
as calculated for the measured conditions at the point and
time of sampling, and the actual oxygen concentration, the
measure is useful because it corrects for temperature, salinity,
and atmospheric pressure which influence the saturation level,
a high deficit can be an indicator of a water quality problem.
Dissolved
solids
Inorganic material dissolved in water or liquid wastes, excessive dissolved solids make
water
unsuitable for drinking or industrial uses,
(see TDS, total dissolved solids).
DO,
Dissolved oxygen
The amount of oxygen gas
dissolved in a given quantity of water at a given temperature
and atmospheric pressure, usually expressed as a concentration in parts per million, ppm, or as a percentage of saturation.
DO
deficit, Dissolved oxygen deficit
The difference between the oxygen saturation value in water
as calculated for the measured conditions at the point and
time of sampling, and the actual oxygen concentration, the
measure is useful because it corrects for temperature, salinity,
and atmospheric pressure which influence the saturation level,
a high deficit can be an indicator of a water quality problem.
DOM,
Dissolved organic matter
Carbon compounds in water
solution, generally from the decomposition of natural plant
and animal tissues, but including some anthropogenic
contaminants.
Domestic
Of or related to a household or dwelling
as opposed to an industry.
Domestic
water use
Water used for household
purposes, such as drinking, food preparation, bathing, washing
clothes, dishes and dogs, flushing toilets and watering lawns
and gardens, most domestic water is delivered to homes by a
public water supply facility.
Drainage
area
The
drainage area of a stream or river at a specified location
is that area, measured in a horizontal plane, enclosed by a
topographic divide from which direct surface runoff normally
drains by gravity into the stream above the specified location.
Drainage
basin
The land
area where precipitation runs off into streams, rivers, lakes and reservoirs,
a land feature that can be identified by tracing a line along
the highest elevations between two areas on a
map, often a ridge, large drainage basins contain many smaller
drainage sub-basins, (see watershed).
Drawdown
A lowering of the ground water surface caused
by pumping from an aquifer or lowering the
water surface in a reservoir by
releasing
water either through the turbine or outlet pipes or over
the spillway.
Drinking
water
A water supply, treated
or untreated which is intended for human consumption and uses and which is considered
to be free of toxins and pathogenic bacteria, cysts or viruses, potable water,
fit to drink, potable water that has or is to be treated additionally, to enhance
aesthetic quality and/or reduce mineral content plus other known or unknown,
undesirable substances: by one or more point-of-use water processing devices
or systems or purified bottled water.
Dyne
Metric unit of force, energy needed to accelerate 1 gram at 1
centimetre/second2.
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E
Effluent
The out-flow water or waste water from any
water processing system or device, softeners, filters or reverse
osmosis units,
the product water of a given water treatment system, alternatively a general
term in waste water treatment for the final water which is discharged from a
treatment plant, usually into a natural flowing river or stream, after complete
treatment steps which meet current effluent water quality standards, effluent
water is often recycled as irrigation water for golf courses, parklands and some
agricultural applications, particularly a liquid, that enters the environment
from a point source, generally refers to wastewater from a sewage treatment or
industrial plant.
Egg
A large immobile gamete produced
by the female organism which contains one haploid set of chromosomes and unites with the sperm to bring about fertilization.
Electrodialysis
The salts are extracted from
the water by using a membrane with an electrical current to separate
the ions, positive ions go through one membrane, while the negative
ions flow through a different membrane, leaving the fresh
water behind.
Emergent
wetlands
Marshes in which
vegetation is rooted underwater with only the tops exposed,
in contrast to
fully submerged aquatic vegetation
or upland habitats where the roots are also above the water
surface.
Enteric
Associated with the gut or intestines of
animals or gut products such as feces.
Enteric
viruses
A group of viruses associated with human
feces found in water.
Enterocci
Bacteria species which live in the
gut of man or other homeothermic animals, some are pathogens, often used instead
of fecal coliform bacteria as an indicator of water contamination.
Epibenthic
Located at the surface of the sediments, generally referring
to algae.
Epilimnion
The upper,
warmer, less dense zone of water in a lake, separated by the
fairly thin thermocline zone, from the lower, colder, denser
zone of water, the hypolimnion.
Erg
Metric unit of work, 1 dyne over a distance of 1 centimetre.
Erosion
The wearing away of the land
surface by wind, water, ice or other geologic agents, occurs naturally
from weather
or runoff but is often intensified by human land use practices, erosion is a
source of sediments, suspended sediments, TDS, total
dissolved solids, particulate matter turbidity and solutes in
natural waters.
Estuary,
Estuaries, Estuarine zone
The lower portion of a river where the ocean and the river mix, the semi-enclosed zone along a coastline where fresh
water meets and mixes with the ocean, such as a bay, mouth of a river, salt
marsh or lagoon, deepwater tidal habitat and tidal wetland,
they are usually partially enclosed by land but have free access
to the ocean and are at least occasionally diluted by fresh
water runoff from the land.
Eukaryotic
Organisms whose cells have a nucleus, chloroplasts in
plants and mitochondria, (see
prokaryotic).
Euphotic
The surface layer of an ocean, lake, or other body of water into
which light can penetrate, also known as the zone of photosynthesis.
Eutrophic
Having a large or excessive
supply of plant
nutrients, nitrates and phosphates, usually
resulting
in an increase in biomass and productivity,
(see oligotrophic).
Eutrophication
The process of increasing
the nutrients, primarily nitrate and phosphate, content of natural
waters, usually resulting in an increase in biomass and productivity of algae which may result in the depletion of the oxygen concentration in the water leading to a fish kill, from natural erosion and
runoff from the land or from anthropogenic sources.
Evaporation
The change of state from
a liquid to a gas, the change by which any substance is converted
from a liquid state and carried off as a vapor, the process of
liquid water becoming water vapor from water surfaces, land surfaces
and snow fields, (see condensation, sublimation, vapourization,
transpiration, evapotranspiration, volatilization).
Evapotranspiration
The combination of evaporation and transpiration of
water into the atmosphere from living
plants, the water surface and soil.
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F
Fecal
Refers to waste matter,
feces, from the gut or gastrointestinal tract of animals.
Fecal
coliform bacteria
Enteric bacteria which ferment lactose with
gas and acid formation at a temperature typical of warm-blooded animals, in water,
fecal coliforms are commonly used as an indicator of contamination and are normally
measured using filtration and culture on disk media, the portion of the coliform
bacteria group which is present in the intestinal tracts and feces of warm-blooded
animals, a common pollutant in water, (see most probable
number, MPN).
Fen
A wetland that is at the
water table and has a direct hydraulic connection
to it, fens
accumulate peat and the vegetation is dominated
by sphagnum moss and small herbs.
Fertilization
The process where haploid eggs and sperm unite
to form a diploid zygote and begin a new
generation.
Filter
A device used to remove solids from a mixture or to separate
materials, materials are frequently separated from water
using filters, a screening device
or porous substance used
as a strainer for removing solid material from liquids.
Filtering,
Filtration
Passing a solvent with particulate material suspended in
it through a material which allows the solvent to
pass but retains the particulates, the mechanical
process which removes particulate matter
by separating water from solid material, by passing it through
a filter such as sand
in many water filtration plants.
Flagella
Several long stout hairs on the cell surface
which are used for locomotion or food gathering in
many microscopic organisms and their larvae.
Flagellate
Having several long stout hairs on the cell surface which are
used for locomotion or food gathering.
Flocculation
A large scale
treatment process involving gentle stirring whereby small particles
in flocs are collected into larger particles so their weight
causes them to settle to the bottom of the treatment tank,
(see coagulation).
Flood
An overflow or inundation that comes from
a river or other body of water and causes or threatens
damage, it can be any relatively high streamflow
overtopping the natural or artificial banks in any
reach of a stream, also
a relatively high flow as measured by either gauge height or discharge
quantity.
Flood
plain
A strip of relatively flat and normally dry
land alongside a stream, river or lake that is covered by water during a flood,
land next to a river that becomes covered by water when the river overflows its
banks.
Fluoridated
A compound that has been
reacted with the halide fluorine and now contains at least one
fluorine atom in the molecule.
Flow
The quantitative rate of
water discharged from a source, or passing by a given point,
expressed as volume per unit of time, (see CFS,
cubic
feet per second).
Flushing
A measure of how often, usually measured
in years, water is replaced in a reservoir, bay or
other system, based upon flow rates
into
and out of the system, (see residence time).
Food
chain
The transfer of food energy from producers through
a series of consumers.
Food
web
A series of inter-connecting and inter-related
food chains.
Fraser
River Estuary
The area of joint social, economic and environmental
concerns which, for the purposes of the FREMP Agreement, means in general, the
land and water outside the boundary of the dykes and between Kanaka Creek and
the outlet from Pitt Lake in the east, the estuary drop off in the west, Point
Grey to the north, and the international boundary to the south, including Boundary
Bay and Semiahmoo Bay.
Fresh
water
Lakes and rivers running
off the land to the sea and having much lower solute
concentrations than the
ocean into which most eventually drain, water containing less than 1,000 parts
per million, ppm of dissolved solids of any type, water that contains less than
1,000 milligrams per liter, mg/L, of dissolved solids, generally, more than 500
mg/L of dissolved solids is undesirable for drinking and many industrial uses,
(see saline water).
Freshet
An influx of freshwater inflow, for example
following seasonally high rain and snowfall or the
spring melt.
Freshwater
An adjective to describe water that meets
the definition of fresh water.
Fully
recorded
The situation where all the available water
in a waterbody is allocated or authorized for use through licences.
Fungi,
fungus
A major group of multicellular organisms
that are non-photosynthetic and often saprophytic,
pathogenic or parasitic.
Furans
Toxic organic compounds containing
a specific complex aromatic ring structure and
containing at least one chlorine atom in
the molecule, (see dioxins).
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G
Gamete
Sperm produced by the male
organism or eggs produced by the female organism, which contain
one haploid set of chromosomes, they unite
to cause fertilization and a diploid zygote.
Gastropod
Organisms in the Class Gastropoda of the Phylum Mollusca, the
snails and similar organisms with an asymmetrical, spirally-coiled
shell.
Geometric
mean
The Nth root of the product
of N observations, (see arithmetic mean).
Grab
sample
A single sample taken at
a given place and time, (see composite sample).
Green
Algae
A common algae group, often green in colour,
with nucleated cells and photosynthetic pigments contained in organelles called
chloroplasts.
Greywater
Wastewater from clothes washing machines,
showers, bathtubs, handwashing, lavatories and sinks that are not used for disposal
of chemical or chemical-biological ingredients or feces, (see blackwater).
Ground
water
Water within the earth that supplies wells and
springs, water in the zone of saturation where all openings
in rocks and
soil are filled, the upper surface of which forms the water table,
water that
flows in aquifers under the surface of the
land and not on the surface, water
that flows or seeps downward and saturates soil
or rock, the upper surface of
the saturated zone is called the water table,
water beneath the surface of the
ground, consisting largely of surface water that has seeped
down, water beneath
the earth's surface, occurring in aquifers at one or more depth
levels, (see
surface water).
Ground
water hydrology
The branch of hydrology
that deals with ground water, its occurrence
and movements, its replenishment
and depletion, the properties of rocks that control ground
water movement and storage
and the methods of investigation and utilization of ground water.
Ground
water recharge
The inflow of water to a ground
water reservoir, primarily from the surface, infiltration
of rain and snowfall and its
movement to the water table is one form of natural
recharge, the volume of water
added by this process, (see ground water).
Ground
water reservoir
An aquifer
or aquifer system in which ground water
is stored, water may be placed in the
aquifer by artificial or natural means.
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H
Habitat
A
place within an ecosystem with a particular kind of environment whereby organisms,
populations or communities live, feed, reproduce
or grow.
Halide
One of the very reactive elements in column
7 of the periodic table that are only one electron short of a full outer orbital,
primarily fluorine, chlorine and bromine.
Halogenated
A compound that has been reacted with, and
now contains, one of the elements in column 7 of the periodic table that are
only one electron short of a full outer orbital, primarily fluorine, chlorine
and bromine.
Haploid
The condition when there is only one set
of chromosomes in a cell which occurs after meiosis
to form eggs and sperm.
Hard
water
Water containing a high level of calcium,
magnesium, and other minerals, hard water reduces the cleansing power of soap
and produces scale in hot water lines, boilers and appliances.
Hardness
(water)
A condition caused predominantly by dissolved
salts of calcium, magnesium and iron, such as bicarbonates, carbonates, sulfates,
chlorides and nitrates, a water-quality indicator of the concentration of alkaline
salts in water, hard water requires more soap, detergent or shampoo to raise
a lather.
Headwaters
The source and upper reaches of a stream,
also the upper reaches of a reservoir, the water upstream from a structure or
point on a stream, the small streams that come together to form a river, any
and all parts of a river basin except the mainstream river and main tributaries.
Heavy
metals
Metallic elements of high molecular weight,
typically with specific gravities greater than 5, a few
examples include copper, lead and zinc.
Hepatic
With reference to the liver.
Hermaphrodite
An organism containing functional male and
female reproductive organs.
Homeothermic
Animals which control their own body temperature
at some fixed value, warm-blooded animals,
(see poikilothermic).
Hydraulic
Related to water and the flows and pressures
within a connected water-containing system.
Hydrograph
A chart that measures the amount of water flowing past
a specified point as a function of time.
Hydrologic
With reference to water and the water
cycle in the environment.
Hydrologic
cycle
The natural pathway water follows
as it changes between liquid, solid, and gaseous states; biogeochemical
cycle that moves and recycles water in various forms through the
environment, evaporation
from oceans to the atmosphere, rain and snowfall
to the earth's surface, replenishment
of ground water, runoff, uptake
by plants, and storage in oceans and ice caps,
the movement of water from
the atmosphere to the earth and its return to the atmosphere through
condensation,
precipitation, evaporation and transpiration,
the cyclic transfer of water from the
Earth's surface via evapotranspiration into the
atmosphere, from the atmosphere via precipitation
back to earth, and through runoff into streams,
rivers, and lakes and ultimately
into the oceans,
(see water cycle).
Hydrology
The science that deals with
the hydrologic cycle or water cycle in the environment-land, soil and
atmosphere;
properties, distribution and circulation of water.
Hydrophobic
Literally, hating water, materials that do
not dissolve in water but tend to dissolve in organic solvents and
fats or sorb
to sediments, (see hydrophyllic).
Hydrophyllic
Literally, loving water materials that do
dissolve in water not in organic solvents and fats and are found in the water
column, (see hydrophobic).
Hypolimnion
The colder, lower, denser
zone of water in a lake, separated by the fairly thin thermocline zone, from
the upper, warmer, less dense zone, the epilimnion.
Hypoxia
Depletion of dissolved oxygen in water to
low levels, for example less than two mg/L, which can result from natural or
human introduction of materials with a high BOD or from eutrophication resulting
from high nutrient concentrations, (see anoxia, anaerobic).
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I
Impermeable
A surface or membrane through which water,
or other liquids, will not penetrate, a layer of solid material, such as rock
or clay, which does not allow water to pass through, any material that does not
permit fluids to penetrate.
Impervious
A material through which water, or other
liquids, will not penetrate and thus must run off over the surface or accumulate
on the top, surfaces with a low capacity for soil infiltration, paving, roofs,
roadways or other human structures, impervious cover increases runoff and affects
the quantity and composition of non-point source pollution, the quality or state
of being impermeable, resisting penetration by water or plant roots.
Indicator
organism
Microorganisms, such as coliform
bacteria,
that are not in themselves harmful but whose presence is indicative of possible
pollution or the presence of other more harmful microorganisms which,
through its population size or condition, mirrors environmental conditions
within an ecosystem.
Indicator
tests
Tests for a specific contaminant,
organism,
group of contaminants or constituent which
signals the presence
of something else, coliforms indicate
the possible presence of other
pathogenic bacteria, tests
for a specific
contaminant, or constituent which signals the
possible presence of something else.
Industrial
water use
Water used for industrial purposes
in such industries as steel, chemical, paper and petroleum
refining, primarily from private sources,
such as local wells or withdrawal points in
a river, but
some comes from public sources.
Infiltration
Flow of water from the land surface into
the subsurface.
Initial
dilution zone
Areas immediately adjacent to a wastewater
discharge in which chronic water quality objectives for water or sediment, but
not those for fish, may be exceeded; however, they may not exceed the acute objectives;
they are defined on a site-specific basis and may not encroach on water intakes,
bathing beaches, shellfish beds, fish spawning and rearing areas, areas of sensitive
aquatic vegetation or other specified sensitive areas.
Injection
well
A well constructed for the purpose of injecting
treated wastewater directly into the ground, wastewater is generally pumped into
the well for dispersal or storage into a designated aquifer, one that does not
deliver drinking water, an unused aquifer or below the levels of fresh
water.
Inorganic
chemicals or compounds
Usually chemicals or compounds which do not
contain carbon atoms or if so the carbon atoms are not connected directly to
each other in long chains, generally substances not made by living organisms.
Instream use
Use of water that does not require withdrawal or
diversion from its natural watercourse, the use
of water for navigation, recreation and habitat for
fish and wildlife, (see contact recreation,
non-contact recreation).
Intake
The place at which a fluid is taken into
a channel or pipe, the location where water is withdrawn
from a stream.
Invertebrate
An organism without a backbone.
Ion
A negatively or positively charged atom or
molecule which has either an excess or shortage,
respectively, of electrons.
Irrigation
water
Water application on lands to assist in the
growing of crops and pastures or to maintain vegetative growth in recreational
lands, such as parks and golf courses, water which is applied to assist crops
in areas or during times where rainfall is inadequate, the controlled application
of water for agricultural purposes through man-made systems to supply water requirements
not satisfied by rainfall.
Isopod
A member of the Crustacean Order Isopoda,
small but generally visible species flattened from
top to bottom, common benthic and epibenthic
invertebrates.
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J
Jet
A concentrated, high velocity flow of
water
capable of causing erosion, used in mining some
placer deposits to wash the unconsolidated
deposits into sluice boxes.
Joule
The metric unit of work or energy, 1 x 107
ergs, 1 joule is about 0.7375 foot-pounds.
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K
Kilifish
Small oviparous Cyprinodontidae
or ovoviviparous Poeciliidae, fish used in bioassays and
for
mosquito control or as bait.
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L
Lacustrine
Relating to a lake environment.
Lagoon
A shallow pond where sunlight,
bacterial action and oxygen work to purify wastewater, typically used for the
storage of wastewaters, sludges, liquid wastes or spent nuclear fuel, a shallow
sound, channel or pond, near and generally connected to, a larger body of water.
Lake
A generally permanent inland body of fresh
water of considerable size occupying a basin or
hollow in the earth's surface.
Larva
Singular, the pre-adult form in which some
animals with multiple life stages hatch from the egg.
Larvae
Plural, the pre-adult form in which some
animals with multiple life stages hatch from the eggs.
Leachate
Water containing contaminants which
leaks
from a disposal site such as a landfill or dump.
Leaching
Extraction or flushing
out of dissolved or suspended
materials from the soil, solid waste or another
medium by water or other liquids as they percolate
down through the medium to ground
water or flow laterally through the
waste material, the process by which soluble
materials in the soil, such
as salts, nutrients, pesticide
chemicals or contaminants, are washed
into a lower layer of soil or are dissolved and
carried away by water.
Lentic
Static or standing, non-flowing waters such
as lakes, ponds and reservoirs, (see
lotic).
Limnology
The scientific study of physical, chemical
and biological conditions and interactions in lentic
systems, lakes, ponds and reservoirs.
Littoral
zone
Area on or near the shore of a body of water
in relatively shallow water.
Livestock
water use
Water used for livestock watering,
feed lots, dairy operations, fish farming, and other on-farm
needs.
Loading
The rate of introduction of a constituent
or contaminant to a receiving water from the environment, significant
in relation to the volume and circulation of the receiving water, problems occur
when high loadings occur into receiving waters with limited assimilative
capacity.
Lotic
A flowing body of fresh
water, such as a
river or stream, (see lentic).
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