Glossary extracted starting with manual seeds, with BOW for the domain gel and language EN

scrapersaquatic invertebrates that feed by scraping the surface of rocks for algae
aerated lagoona holding and/or treatment pond that speeds up the natural process of biological decomposition of organic waste by stimulating the growth and activity of bacteria that degrade organic waste.
hydrologyScience concerned with the occurrence, distribution, and circulation of water on the earth.
hydrologic cyclenatural pathway water follows as it changes between liquid, solid, and gaseous states; biogeochemical cycle that moves and recycles water in various forms through the ecosphere
aquiferA geological formation or group of formations capable of receiving, storing and transmitting significant quantities of water (Water and Rivers Commission 2000a).
meander widthAmplitude of a fully developed meander measured from midstream to midstream.
snagFallen trees and dead branches in the river channel.
environmentThe sum total of all the external conditions that effect an organism, community, material, or energy.
soft waterWater that contains low concentrations of multivalent cations, such as calcium and magnesium
snow creepA continuous, extremely slow, downhill movement of a layer of snow.
confined aquiferan aquifer that lies between two rock layers of very low permeability
holding timethe maximum amount of time a sample may be stored before analysis.
rechargeRainfall that drains past the root zone and reaches the groundwater.
deltaA delta is a large, silty area at the mouth of a river at which the river splits into many different slow-flowing channels that have muddy banks
dredgingDigging up and removing material from wetlands or waterways, usually to make them deeper or wider.
diversitySee Biodiversity
boiling pointThe temperature at which a liquid changes to a vaporous state
hydraulic gradientThe change in hydraulic head over some specified distance.
slope stabilityThe resistance of a natural or artificial slope or other inclined surface to failure by landsliding (mass movement).
currentA horizontal movement of water, such as the Gulf Stream off the east coast of North America, or air, such as the jet stream.
bed sediment dischargePart of the total sediment discharge that is composed of grain sizes found in the bed and is equal to the transport capability of the flow.
hecHydrologic Engineering Center; The part of the U.S
fid=Flame Ionization Detector, a detector used in GC chromatography, very sensitive but destroys the sample due to combustion
hardpanA layer of nearly impermeable soil beneath a more permeable soil, formed by natural chemical cementing of the soil particles.
streamthe 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.
transportationA process where the river moves, or transports materials (it's load) from one place to another.
hydrologic unitA distinct watershed or river basin defined by an eight-digit code.
transport capacitythe capacity of a river to carry sediment in suspension or to move sediment along the riverbed.
tonnes/dTonnes per day.
fishwaya structure designed to enable fish to move over a physical barrier (dam or weir) in a waterway.
land applicationdischarge of wastewater onto the ground for treatment or reuse.
secondary productionmaterial that is transformed by consumers (eaten or decomposed)
holdA feature common to thermometers allowing you to freeze the display at a given measurement without additional inputs for easier reading
critical shear stressMinimum amount of shear stress required to initiate soil particle motion.
ephemeral streamsStreams that flow only in direct response to precipitation and whose channel is at all times above the water table.
stream segmentrefers to the surface waters of an approved planning area exhibiting common biological, chemical, hydrological, natural, and physical characteristics and processes
cavitationThe boiling of a liquid caused by a decrease in pressure rather than an increase in temperature.
frictionIn meteorology, it is the turbulent resistance of the earth on the atmosphere
weirUsually a barrier constructed to catch upstream migrating adult fish.
macroinvertebratesInvertebrates (animals without backbones) large enough to be seen without a microscope
biofilmsLayered groups or communities of microbial populations.
arctic air massAn air mass that develops around the Arctic, it is characterized by being cold from surface to great heights
horsetail fallsA falls that descends a very nearly vertical rock face, maintaining some contact with it
effluentEffluent is wastewater (like sewage water or factory runoff) that flows from a factory or other facility.
peak flowThe highest discharge achieved during a storm event.
hydraulic conductivitythe rate at which water can move through a permeable medium.
flood spawnersIn the River Murray, include fish species of Golden perch and Silver perch which spawn and recruit following flow rises and during periods of floodplain inundation.
meridional flowAtmospheric circulation in which the north and south, or meridional, component of motion is unusually pronounced
fahrenheitA scale of temperature originally defined by having 0° as the lowest obtainable temperature with a mixture of water, ice and salt and 96° as the temperature of the human body
dissolved fractionThe part of a water sample passing through a 0.45 µm pore size filter paper
uv-vis spectroscopyis a technique to investigate conjugation within molecules
butt endThe bottom end of a cutting taken from a riparian plant that will root if planted in soil (it is opposite the budding tip's end of the cutting).
prehistoricbefore written historic records
depressionIn meteorology, it is another name for an area of low pressure, a low, or trough
benthicrefers to the bottom of a body of water benthic macroinvertebrates: spineless animals that inhabit the bottom of streams and lakes; visible to the eye; aquatic worms, snails, clams, immature stages of aquatic insects
drainage areaof a stream at a specified location is that area, measured in a horizontal plane, enclosed by a topographic divide from which direct surface runoff from precipitation normally drains by gravity into the stream above the specified location.
diluting waterdistilled water that has been stabilized, buffered, and aerated
retention/retainRetention is defined as the process of preventing rainfall runoff from being discharged into receiving water bodies by holding it in a storage area
water dependent ecosystemsThose parts of the environment, the species composition and natural ecological processes of which are determined by the permanent or temporary presence of water resources, including flowing or standing water and water within groundwater aquifers.
peak flowin a wastewater treatment plant, the highest flow expected to be encoutered under any operational conditions, including periods of high rainfall and prolonged periods of wet weather.
bulkingIncreasing the water discharge to account for high concentrations of sediment in the flow.
run-offWater that runs off the soil's surface
icea solid form of water.
artesian wella water well drilled into a confined aquifer where enough hydraulic pressure exists for water rise in the well to a height above the top of the aquifer in the subsurface
dead endthe end of a water main that is not connected to other parts of the distribution system.
froude numberDimensionless number expressing the ratio of inertial force to gravity force in a fluid.
algaesimple rootless plants that grow in sunlit waters in proportion to the amount of available nutrients
short circuitingwhen some of the water in tanks or basins flows faster than the rest; shortcircuiting may result in shorter contact, reaction, or settling times than calculated or presumed.
halophyticRefers to a plant that can tolerate or thrive in alkaline soil rich in sodium or calcium salts; tolerant of saline conditions.
aquiferA body of rock that is sufficiently permeable to conduct groundwater and to yield significant quantities of water to wells and springs.
healthy working riverIn the case of The Living Murray, a healthy working river is one that is managed to provide a compromise, agreed to by the community, between the condition of the river and the level of human use.
frostThe covering of ice crystals that forms by direct sublimation on exposed surfaces whose temperature is below freezing.
drainage basinwatershed
headcuttingThe action of a bedscarp or headward erosion of a locally steep channel or gully.
macroinvertebrateAn invertebrate (animal without a backbone) that is larger than 1 mm.
lithosphereThe solid, outer portion of the earth's crust coupled to the rigid upper mantle
allochthonousDerived from an external source, for example, organic matter entering a stream or lake but derived from adjacent terrestrial areas.
snowfallThe rate at which snow falls, usually expressed in inches of snow depth over a six hour period.
viscosityA measure of the resistance of a fluid to flow
sedimentSoil or mineral material transported by water or wind and deposited in streams or other bodies of water.
channeledChanneled means grooved or cut deeply.
freezing pointis the temperature at which a liquid becomes a solid
thermosphereA thermal classification, it is the layer of the atmosphere located between the mesosphere and outer space
mixing zonea limited volume of receiving water that is allocated for diluting a wastewater discharge without causing adverse effects to the overall water body.
catchment(1) The catching or collecting of water, especially rainfall
publicly-owned treatment worksa wastewater treatment plant that is owned by a state, unit of local government or Indian tribe, usually designed to treat domestic wastewaters
glenA long narrow valley, often U-shaped with small cliffs on the sides, carved by a stream
interfacethe common boundary between two substances such as water and a solid, water and a gas, or two liquids such as water and oil.
groundwaterSubsurface water and underground streams that can be collected with wells, or that flow naturally to the earth's surface though springs.
water qualitythe chemical, physical, biological, radiological, and thermal condition of water.
international date lineThe line of longitude located at 180° East or West (with a few local deviations) where the date changes by a day
grab samplea sample taken at a given place and time
oxbow lakea U-shaped water body formed when a meander bend is cut off from the mainstem of a river or stream to create a lake.
eddy currentVortex‑type motion of a fluid flowing contrary to the main current, such as the circular water movement that occurs when the main flow becomes separated from the bank.
economic valuesIncludes water body uses, stormwater use, economic values of the receiving environment (e.g
deglaciationDisappearance by melting of ice covering an area
turbulent flowFluid flow in which the velocity at any point varies erratically in magnitude and direction
environmentaggregate of external conditions that influence the life of an individual organism or population.
dike(1) (Engineering) An embankment to confine or control water, especially one built along the banks of a river to prevent overflow of lowlands; a levee
standard deviationA measure of how much variation there is from the average across a data set.
filter fabricGeosynthetic fabric that serves the same purpose as a granular filter blanket.
dischargethe volume of water that passes a given point within a given period of time
crossingRelatively short and shallow reach of a stream between bends; also crossover or riffle.
ground waterits 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.
backwater poolA pool that formed from an eddy along a channel margin as a result of an upstream obstruction like a large tree, rootwad, or boulder.
environmental water provisionsThe water regimes that are provided as a result of the water allocation decision-making process taking into account ecological, social and economic impacts
mainstem survivalThe proportion of anadromous fish that survive passage through the dams and reservoirs while migrating in the Columbia and Snake rivers.
dikeAn impermeable linear structure for the control or containment of overbank flow
fogbowA whitish semicircular arc seen opposite the sun in fog
miltsperm-filled milky substance released by male fish to fertilize eggs
synthetic organic chemicalsman-made organic chemicals
dissolved oxygenThe amount of oxygen freely available in water and necessary for aquatic life and the oxidation of organic materials.
flow slideSaturated soil materials which behave more like a liquid than a solid
streambedpart of the stream over which water moves; substrate
sandbarAn accumulation of alluvium - usually sand or gravel - caused by a decrease in sediment transport capacity in an overwide channel.
incised riverA river that erodes its channel by a process of degradation to a lower base level than existed previously or is consistent with the current hydrology.
habitatan area where plants and animals live
geomorphologyGeomorphology is the scientific field that investigates how landforms are formed on the Earth (and other planets).
benthicOf, or associated with, the bottom of a water body.
functionThe physical, chemical and biological processes, services and values that occur in an ecosystem (e.g., floodplain, stream, wetland) as a result of their structure and composition.
acreA measure of area equal to 43,560 square feet (4,046.87 square meters)
nutrient cyclethe cyclic conversions of nutrients from one form to another within biological communities
rifflesHigh points in a stream or river channel representing bedrock bars or accumulations of relatively coarse material
design flowDischarge that is selected as the basis for the design or evaluation of a hydraulic structure.
isohelA line drawn through geographic points having equal duration of sunshine or another form of solar radiation during a specified time period.
ukasAn acronym for United Kingdom Accreditation Service, the organization tasked by the British government with the maintenance and administration of national standards
macrophytesWater plants that are not algae and which may either float or be attached to a substrate.
contraction scourContraction scour, in a natural channel or at a bridge crossing, involves the removal of material from the bed and banks across all or most of the channel width
sun dogEither of two colored luminous spots that appear at roughly 22° on both sides of the sun at the same elevation
specific yieldthe amount of water a unit volume of saturated permeable rock will yield when drained by gravity.
seagrassSeagrasses are the 'grass meadows' of coastal waters. 
coalescenceThe merging of two water drops into a single larger drop.
speedSee response time.
redda nest in the streambed in which salmon and trout lay their eggs; the eggs incubate, then hatch in the gravel
hazeA suspension of fine dust and/or smoke particles in the air
e. coliA group of bacteria, Escherichia, that reside in the intestinal tracts of humans and many animals and can cause food poisoning, urinary infections and enteritis.
key watershedAs defined by National Forest and Bureau of Land Management District fish biologists, a watershed containing (1) habitat for potentially threatened species or stocks of anadromous salmonids or other potentially threatened fish, or (2) greater than 6 square miles with high-quality water and fish habitat.
hydrocarbonschemical compounds that consist entirely of carbon and hydrogen; also referred to as volatile organic compound.
drainage basinThe area drained by a river and its tributaries
targetA numerical concentration limit or descriptive statement relating to an aspect of water management aspired to as part of the LEWMP.
wastewaterwater containing waste including greywater, blackwater or water contaminated by waste contact, including process-generated and contaminated rainfall runoff.
perennial streamA stream that normally contains flowing water at all times.
watershed restorationImproving current conditions of watersheds to restore degraded fish habitat and provide long-term protection to aquatic and riparian resources.
cambaThe China Australia Migratory Bird Agreement, a treaty between Australia and China with the aim of preserving areas that provide habitat for internationally migrating birds within the tropics or the southern hemisphere.
riparianRiparian means located by the banks of a river, stream, or other body of water.
anabatic windA wind that is created by air flowing uphill
periphytonalgae growing on surfaces in a stream, lake, or ocean
lagoon(1) A shallow pond where sunlight, bacterial action, and oxygen work to purify wastewater
evapotranspirationThe loss of water from a land area through evaporation from the soil and through plant transpiration.
glideA section of stream that has little or no turbulence.
wella 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.
turbiditya cloudy condition in water due to suspended silt or organic matter.
average annual rechargeamount of water entering the aquifer on an average annual basis
fresh waterWater found rivers, lakes, and rain, that is distinguished from salt water by its appreciable lack of salinity.
lockAn enclosed dam chamber with gates at each end that allow water to be admitted and released
combined sewer overflowAn outlet for stormwater and untreated sewage during large rainfall or runoff events.
normal operating zoneThe elevation range within which main-river reservoirs are operated for power production and summer mosquito control
incubationthe process of keeping eggs in a favorable condition for hatching
waterproofA non-technical term used to describe instruments that are protected from the ingress of liquids
organismany form of animal or plant life.
fishwaysStructures that provide fish with passage past an obstruction or stream.
sandSmall substrate particles, generally referring to particles less than 2 mm in diameter
cloudA visible collection of minute particle matter, such as water droplets and/or ice crystals, in the free air
water surface elevationthe elevation of a water surface above or below an established reference level, such as sea level.
wild riversRivers or sections of rivers that are free of impoundments and generally inaccessible except by trail, with watersheds or shorelines essentially primitive and waters unpolluted.
headIn the hydrological sense, refers to water pressure as a result of flow, usually as a result of a pressure gradient created by the movement of water.
current meterInstrument used to measure flow velocity.
nocturnal thunderstormsThunderstorms which develop after sunset
tidal marshlow, flat marshlands traversed by channels and tidal hollows, subject to tidal inundation; normally, the only vegetation present is salt-tolerant bushes and grasses.
biotechnical engineeringCountermeasure techniques that combine the use of vegetation with structural (hard) elements.
seepagepercolation of water through the soil from unlined canals, ditches, laterals, watercourses, or water storage facilities.
smolta juvenile anadromous fish that has undergone physical changes to prepare for life in saltwater
flash floodA flood that crests in a short length of time and is often characterized by high velocity flows.
channelizationThe process of changing (usually straightening) the natural path of a waterway.
vortex rocksRocks placed in a streambed to help direct flows for the formation of meanders and creation of riffles and pools
watershedall the land area that drains into a particular body of water
salinity gradientsChanges in salt concentration.
infiltrationThe movement of water from the surface to the subsoil and at times, ultimately to the underlying aquifer.
samphireA leafless shrub that is tolerant of saline conditions
green filamentous algaeHair-like filaments of algae often found floating on the surface of water or clumped on the stream bed.
vertical visibilityThe distance an observer can see vertically into an undefined ceiling, or the height corresponding to the top of a ceiling light projector beam, or the height at which a ceiling balloon disappears during the presence of an indefinite ceiling.
snow devilA small, rotating wind that picks up loose snow instead of dirt (like a dust devil) or water (like a waterspout)
foraging habitatareas in which a fish searches for food
wet bulb depressionDependent on the temperature and the humidity of the air, it is the difference between the dry bulb and the wet bulb readings.
moleculethe smallest division of a compound that still retains or exhibits all the properties of the substance.
baran accumulation of alluvium (usually gravel or sand) caused by a decrease in sediment transport capacity on the inside of meander bends or in the center of an overwide channel.
estuaryan area of a river where the fresh water meets the salt water
streamalso 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.
water pollutionAn unusually high amount of a chemical in a water body that has the potential to cause an environmental impact.
nist-traceableIndicates that a given instrument has been calibrated using standards that have an accuracy certified by the National Institute of Standards and Technology (NIST).
cribFrame structure filled with earth or stone ballast, designed to reduce energy and to deflect streamflow away from a bank or embankment.
stagnationlack of motion in water that holds pollutants in place.
faunaA living organism characterised by voluntary movement.
gauging stationA point of demarkation along the route of a stream or river, used for reference marking or water monitoring.
langelier saturation indexan index reflecting the equilibrium pH of a water with respect to calcium and alkalinity; used in stabilizing water to control both corrosion and scale deposition.
re-snaggingRefers to the process of placing woody debris back into channels to improve aquatic fauna habitat.
mattressBlanket or revetment of materials interwoven or otherwise lashed together and placed to cover an area subject to scour.
tcd=Thermal Conductivity Detector, less sensitive than FID, but allows to collect sample
freezingthe change of a liquid into a solid as temperature decreases
overbank flowsthe component of an instream flow regime that represents infrequent, high flow events that exceed the normal channel
boundary layerThe thin layer of the water column immediately above the stream bed where friction virtually stops the current.
united states weather bureauThe official name of the National Weather Service prior to 1970.
weather surveillance radarThe newest generation of Doppler radars, the 1988 Doppler weather radar
biological oxidationdecomposition of complex organic materials by microorganisms
sandstormA strong wind carrying sand particles through the air
larvathe first mobile stage of life after hatching
recruitmentaddition of new fish to a population, usually through natural reproduction or stocking
embankmentAn artificial deposit of material that is raised above the natural surface of the land and used to contain, divert, or store water, support roads and railways, or for other similar purposes.
rapidsRapids are fast-flowing stretches of water formed where the river surface breaks up into waves because rocks are near to the surface.
crustaceansAquatic organisms with a shell
convergenceWind movement that results in a horizontal net inflow of air into a particular region
streambank stabilizationThe lining of streambanks with riprap, matting, etc., or other measures intended to control erosion.
river channelsNatural or artificial open conduits which continuously or periodically contain moving water, or which forms a connection between two bodies of water.
top of bankThe break in slope between the bank and the surrounding terrain.
lumolowest unoccupied molecular orbital
fill(Geology) Any sediment deposited by any agent such as water so as to fill or partly fill a channel, valley, sink, or other depression.
algaeMicroscopic plants that grow in sunlit water containing phosphates, nitrates, and other nutrients
volcanoAn opening in the earth's crust through which steam and lava are forced out.
aquiculturethe raising or fattening of fish in enclosed ponds
noncontact recreationrecreational pursuits not involving a significant risk of water ingestion, including fishing, commercial and recreational boating, and limited body contact incidental to shoreline activity
homois the highest occupied molecular orbital in a molecule
whirlwindA small-scale, rapidly rotating column of wind, formed thermally and most likely to develop on clear, dry, hot afternoons
drainage basinthe area of land drained by a major river system
canyonA very wide and deep chasm with sides comprised of a series of cliffs, carved by a river.
cobblerocks with a grain size between 2.5 to 10 inches
headwaterThe upstream portion of a watershed.
water recyclingthe treatment of urban wastewater to a level rendering it suitable for a specific, direct, beneficial use.
mesosphereThe layer of the atmosphere located between the stratosphere and the ionosphere, where temperatures drop rapidly with increasing height
stream bedThe bottom of a stream.
stream flowvolume of water carried by a stream
rainWater falling to earth in drops that have been condensed from moisture in the atmosphere.
auto-rangeA feature on some thermometers that automatically changes the resolution of the display over a specified range.
heat lightningLightning that appears as a glowing flash on the horizon
soft waterWater that contains low concentrations of metal ions such as calcium and magnesium
climateThe historical record and description of average daily and in seasonal weather events that help describe a region
economic demandThe consumer's willingness and ability to purchase some quantity of a commodity based on the price of that commodity.
caviarripe sturgeon eggs which are processed and salted to be eaten as a spread or used as a garnish
loadThe amount of electric power that is drawn from TVA’s electric system at a given point in time.
open systemsystem in which energy and matter are exchanged between the system and its environment, for example, a living organism.
saltgenerally potassium or ammonium is the cation, used to coagulate       particles in water treatment.
runa part of the stream with smooth, slow to moderate flow, deeper than a riffle
freeboardVertical distance above a design stage that is allowed for waves, surges, drift, and other contingencies.
sedimentSoil particles (sand, silt, clay) that have been transported away from their previous location by the action of water.
granular activated carbonpure carbon heated to promote "active" sites which can adsorb pollutants
species compositionthat portion of an Index of Biotic Integrity that is a metric measuring the number and identity of species.
runoffWater that flows over the ground and reaches a stream as a result of rainfall or snowmelt.
cut bankConcave wall of a meandering stream.
erosionthe wearing away of the land surface by wind, water, ice or other geologic agents
drainage wella well drilled to carry excess water off agricultural fields
jar testa laboratory procedure that simulates a water treatment plant's coagulation/flocculation units with differing chemical doses, mix speeds, and settling times to estimate the minimum or ideal coagulant dose required to achieve certain water quality goals.
dustSmall particles of earth or other matter suspended in the air
acidicThe condition of water or soil that contains a sufficient amount of acid substances to lower the pH below 7.0.
neata term often used in IR spectroscopy, means that only the pure compound was place in the IR beam
colladaA strong, steady wind blowing from the north or northwest in the upper part of the Gulf of California and from the northeast in the lower part.
millibarThe standard unit of measurement for atmospheric pressure used by the National Weather Service
robust brown algae Large brown macroalgae (Phaeophyta) that are found in marine habitats with hard substrate where seagrasses cannot grow
trihalomethaneschemical compounds in which three of the four hydrogen atoms of methane (CH4) are replaced by halogen atoms
runoffRunoff is water that drains into a river (or other body of water) from uncontrolled streams, drains, or sewage lines
debris torrentRapid movement of a large quantity of materials (wood and sediment) down a stream channel during storms or floods
carbamatesa class of new-age pesticides that attack the nervous system of organisms.
flanking lineA line of attached cumulus or towering cumulus clouds of descending height, appearing as stair steps (usually on the southwest side) of the most active part of a supercell.
methyl orange alkalinityA measure of the total alkalinity in a water sample in which the color of methyl orange reflects the change in level.
stream reachAn individual first order stream or a segment of another stream that has beginning and ending points at a stream confluence
riparian bufferAn undisturbed, vegetated strip of land adjacent to a water course.
woody weedsIntroduced shrub like plants which can become pests, such as gorse and blackberries.
wetlandsAreas of seasonally, intermittently or permanently waterlogged or inundated land, whether natural or otherwise, including lakes and floodplains.
lakesInland water bodies that have little or no flow
key watershedAs defined by National Forest and Bureau of Land Management District fish biologists, a watershed containing (1) habitat for potentially threatened species or stocks of anadromus salmonids or other potentially threatened fish, or (2) greater than six square miles with high-quality water and fish habitat.
anti-degradation clausepart of federal and water quality requirements prohibiting deterioration where pollution levels are above the legal limit.
groundwater storage capacityThe space or voids contained in a given volume of soil and rock deposits.
kalemaa violent surf that occurs on the coast of the Guinea region, West Africa.
retention timeis the time interval that passed between the sample injection and the appearance of the peak maximum
disinfection byproductshalogenated organic chemicals formed when water is disinfected.
water quality standardslaws or regulations, promulgated under Section 303 of the Clean Water Act, that consist of the designated use or uses of a waterbody or a segment of a waterbody and the water quality criteria that are necessary to protect the use or uses of that particular waterbody
meander cut-offA channel cut across the neck of a bend (often as a result of movement of a channel over time).
base floodplainFloodplain associated with the flood with a 100-year recurrence interval.
mudflatsMudflats are large area of mud that the tide washes over twice each day
alberta clipperA fast moving, snow-producing weather system that originates in the lee of the Canadian Rockies
acid rainthe acidic rainfall which results when rain combines with sulfur oxides emissions from combustion of fossil fuels.
nick pointA usually less erosive material, such as bedrock or a fallen log, that tends to slow the downward erosion of the stream channel and the upstream migration of a headcut.
vested water rightthe right granted by a state water agency to use either surface or ground water.
acidicThe condition of water or soil in which the amount of acid substances are sufficient to lower the pH below 7.0.
contaminantAn undesirable substance not normally present or an unusually high concentration of a naturally occurring substance
primary productionorganic material produced by plants from inorganic material and sunlight
dry slotAn area of dry, and usually cloud-free, air that wraps into the southern and eastern sections of a synoptic scale or mesoscale low pressure system
overbank flowWater movement that overtops the bank either due to stream stage or to overland surface water runoff.
sac frynewly hatched fish that have not yet absorbed their yolk sac
surface erosionThe detachment and transport of soil particles by wind, water, or gravity
hydraulic problemAn effect of streamflow, tidal flow, or wave action such that the integrity of the highway facility is destroyed, damaged, or endangered.
alluviumUnconsolidated material deposited by a stream in a channel, floodplain, alluvial fan, or delta.
calibrationThe process of adjusting an instrument to be more accurate by comparing it to a reliable standard
non-cohesive soilSoil particles that have no natural resistance to being pulled apart at their point of contact, for example, silt, sand, gravel.
bathythermographA device used to obtain a record of temperature against depth (pressure) in the ocean
upflowan upward flow.
headcuttingChannel degradation associated with abrupt changes in the bed elevation (headcut) that generally migrates in an upstream direction.
arrhenius equationpredicts that the rate of reaction increases if the temperature is raised
stream orderA hydrologic system of stream classification
thawA warm spell of weather when ice and snow melt
air pollutionThe soiling of the atmosphere by contaminants to the point that may cause injury to health, property, plant, or animal life, or prevent the use and enjoyment of the outdoors.
poolA river feature where above average depth and/or width and below average velocity create a calm river section.
certificate of water rightan official document which serves as court evidence of a perfected water right.
catchmentArea of land from which all surface water drains to a common destination, such as a lake of a river.
progradingA formation or geological complex that forms by the deposition of mud and sand at the mouth of a river system during relatively low sea level.
minimum streamflowthe specific amount of water reserved to support aquatic life, to minimize pollution, or for recreation
channel scourThe erosive action of water and sediment that removes and carries away bed and bank material.
ripraprock covering used to protect stream banks from erosion
mesotrophicreservoirs and lakes that contain moderate quantities of nutrients and are moderately productive in terms of aquatic animal and plant life.
casinga tubular structure intended to be watertight installed in the excavated or drilled hole to maintain the well opening and, along with cementing, to confine the ground waters to their zones of origin and prevent the entrance of surface pollutants.
refractionThe bending of light or radar beam as it passes through a zone of contrasting properties, such as atmospheric density, water vapor, or temperature.
invertLowest point in the channel cross section or at flow control devices such as weirs, culverts, or dams.
aquicludea formation which, although porous and capable of absorbing water slowly, will not transmit water fast enough to furnish an appreciable supply for a well or a spring.
regulatedA river or creek where water is released from storage to meet diversion requirements downstream, or to reduce flooding.
type tA more specialized thermocouple sensor pairing two wires made mostly of copper and constantan and using variance in voltage to calculate temperatures—known for greater accuracy and durability—typical in medical or pharmaceutical applications.
epaEnvironmental Protection Agency.  The federal regulatory agency responsible for protecting environmental quality throughout the nation
evaporationThe physical process by which a liquid (or a solid) is transformed to the gaseous state
swampLow, wet land on which grass and trees grow.
mathematical modelNumerical representation of a flow situation using mathematical equations (also computer model).
aquatic ecosystemAny body of water, such as a stream, lake, or estuary, and all organisms and nonliving components within it, functioning as a natural system.
straight-line windsAny surface wind that is not associated with rotation
instream useUse of water that does not require diversion from its natural watercourse
cloudbursta torrential downpour of rain, which by it spottiness and relatively high intensity suggests the bursting and discharge of water from a cloud all at once.
washboardingWhen a stream descends a rock face in many small and rather evenly spaced drops.
response timeThe length of time a given instrument requires to reach a specified percentage of its final reading value
guide bankDike extending upstream from the approach embankment at either or both sides of the bridge opening to direct the flow through the opening
reservoir operations studyA study carried out by TVA to determine whether changes in its reservoir operating policies would produce greater overall public value
creeka small stream of water which serves as the natural drainage course for a drainage basin
averageA measure of the mean, or middle-point, of a data set when there is more than one measurement taken.
mitigationTo alleviate, or compensate for, the impact of environmental degradation, often through replacement of lost ecological functions or values at a nearby location.
exclusion ruledescribes the fact that a molecule with a center of inversion has peaks either in the IR or in the Raman spectrum, but not in both.
bed loadthe particles in a stream channel that mainly move by bouncing, sliding, or rolling on or near the bottom of the stream.
relative humidityA type of humidity that considers the ratio of the actual vapor pressure of the air to the saturation vapor pressure
boiling pointThe temperature at which a substance in the liquid phase transforms to the gaseous phase
rapidsA reach of stream that is characterized by small falls and turbulent high velocity water.
in-situ vitrificationtechnology that treats contaminated soil in place at high temperatures, at 3,000 degrees Fahrenheit or more.
settleable solidsin sewage, suspended solids that will settle when the sewage is brought to a quiet state for a reasonable length of time, usually two hours.
celsiusA metric scale of temperature, originally defined as having the freezing point of water as 0° and its boiling point as 100°, at standard atmospheric pressure
superheatingthe process at which a liquid is heated above its boiling point without vaporization
drainage basinThe area of land that is drained by a river and its tributaries
attainmentMeeting the Biocriteria standards for the designated aquatic life use.
vapor pressureThe pressure exerted by the molecules of a given vapor
westerliesUsually applied to the broad patterns of persistent winds with a westerly component
virgin flowthe streamflow which exists or would exist if man had not modified the conditions on or along the stream or in the drainage basin.
sedimentSediment is small particles of soil or rocks that are transported by water or the wind.
cordwoodwood pile
driftsNormally used when referring to snow or sand particles are deposited behind obstacles or irregularities of the surface or driven into piles by the wind.
sluicewayVertical slots, generally located near the bottom of a dam, which can be opened to release water from the upstream reservoir without passing it through the turbines
municipal sewagesewage from a community which may be composed of domestic sewage, industrial wastes or both.
lakeseparated by the fairly thin thermocline zone,       from the upper, warmer, less dense zone, the epilimnion.
diversitynumber of species in a particular community or habitat
solventSubstances (usually liquid) capable of dissolving or dispersing one or more other substances.
coliform bacterianon-pathogenic microorganisms used in testing water to indicate the presence of pathogenic bacteria.
clear-water scourScour at a pier or abutment (or contraction scour) when there is no movement of the bed material upstream of the bridge crossing at the flow causing bridge scour.
scenic riversRivers or sections of rivers that are free of impoundments, with shorelines or watersheds still largely primitive, and shorelines largely undeveloped but accessible in places by roads.
hygroscopic nucleipiece of dust or other particle around which water condenses in the atmophere
spawningThe production and/or deposition of eggs by a fish or other aquatic animal.
herblandExtensive community or herbaceous plant species (that is, with non-woody stems).
floodexcess water from a river which spills over its banks
restorationBring back to a former, natural condition
marine watersMarine waters include coastal environments such as beaches and bays.
yieldthe quantity of water expressed either as a continuous rate of flow (cubic feet per second, etc.) or as a volume per unit of time
unravelThe lose material from the edges of a revetment.
sedimentsoil particles, sand, and minerals washed from the land into aquatic systems as a result of natural and human activities.
base flowThe sustained portion of stream discharge that is drawn from natural storage sources, and not affected by human activity or regulation.
inorganicMatter other than plant or animal and not containing a combination of carbon, hydrogen, and oxygen, as in living things.
amprometric titrationa way of measuring concentrations of certain substances in water using the electric current that flows during a chemical reaction.
cirrostratusA cirriform cloud that develops from cirrus spreading out into a thin layer, creating a flat sheetlike appearance
surgeThe increase in sea water height from the level that would normally occur were there no storm
secchi depthA relatively crude measurement of the turbidity (cloudiness) of surface water
abrasionAbrasion is a form of erosion caused by rubbing of fine particles against an object
modelA simulation, by descriptive, statistical, or other means, of a process or project that is difficult or impossible to observe directly.
hydrological cycleThe continual cycle of water between the land, the ocean and the atmosphere.
sole-source aquiferan aquifer that supplies 50 percent or more of the drinking water of an area.
wastewaterThe used water, liquid waste, or drainage from a community, industry, or institution.
hydrologyThe properties, distribution, and effects of water on the earth's surface, below the earth's surface, and in the atmosphere.
windthrowA tree or trees uprooted or felled by the wind.
brackishwater that is not fresh but is not fully salt water
pupastage of a life cycle between larva and adult
sediment trapping efficiencythe ratio of sediment retained within the reservoir to the sediment inflow to the reservoir.
velocityThe speed at which water is flowing, typically reported in feet per second
wettable powderdry formulation that must be mixed with water or other liquid before it is applied.
flood stageThe gage height at which the stream begins to overflow its banks.
scutessmall, bony plates on the outside of the sturgeon that is for protection
toxicity reduction evaluationa study conducted to determine the source(s) of toxicity in a discharge effluent so that these sources can be controlled sufficiently to allow a discharger to comply with their permit limits.
digesterin wastewater treatment, a unit in which anaerobic bacterial action is induced and accelerated in order to break down and stabilize organic matter removed from the treatment process.
soil stabilisationThe use of measures or materials, such as rock lining or vegetation, to prevent the movement of soil when loads are applied to the soil.
extirpatedDescribes a local population of a species that has been eliminated because of loss of habitat, a catastrophic event, or chronic impairment, but still can be found in another location.
hydrologicalRefers to the study associated with water and the hydrological cycle-the way in which water circulates through the atmosphere and biopshere.
tropical waveAnother name for an easterly wave, it is an area of relatively low pressure moving westward through the trade wind easterlies
buffer stripAreas of vegetation through which runoff passes while travelling to a discharge point and which are therefore aligned perpendicular to the direction of flow.
barotropyThe state of a fluid in which surfaces of constant density or temperature are coincident with surfaces of constant pressure
mud slideFast moving soil, rocks and water that flow down mountain slopes and canyons during a heavy a downpour of rain.
rearing habitatplaces in a stream that provide food, resting places, and shelter for young fish
evapotranspirationcombination of evaporation and transpiration of water into the atmosphere from living plants and soil
islandA permanently vegetated area, emergent at normal stage, that divides the flow of a stream
hydrologic unitis a geographic area representing part or all of a surface drainage basin or distinct hydrologic feature.
recharge ratethe quantity of water per unit of time that replenishes or refills an aquifer.
turbidimetera device that measures the cloudiness of suspended solids in a liquid; a measure of the quantity of suspended solids.
assemblagean organism group of interacting species in a given ecosystem, for example, a fish assemblage or a benthic macroinvertebrate assemblage.
piezometric surfacethe imaginary surface to which groundwater rises under hydrostatic pressure in wells or springs.
hydrosphereregion that includes all the earth's liquid water, frozen water, floating ice, frozen upper layer of soil, and the small amounts of water vapor in the Earth's atmosphere.
mackerel skyThe name given to cirrocumulus clouds with small vertical extent and composed of ice crystals
coriolis forceInertial force caused by the Earth's rotation that deflects a moving body to the right in the Northern Hemisphere.
loadingThe total mass of a contaminant discharged during a runoff event
water tableThe water table is the natural level of water in a soil or rock
snagfallen trees and dead branches in the river channel.
boulderslarge rocks with grain size greater than ten inches in diameter
ecosystemthe interacting system of a biological community and its non-living environmental surroundings; a complex system composed of a community of fauna and flora, taking into account the chemical and physical environment with which the system is interrelated.
eclipticThe sun's apparent path across the sky that tracks a circle through the celestial sphere.
bridge openingCross‑sectional area beneath a bridge that is available for conveyance of water.
alluviumSediment or loose material such as clay, silt, sand, gravel, and larger rocks deposited by moving water.
base flowsthe component of a flow regime that represents normal flow conditions between precipitation events
sleetprecipitation which is a mixture of rain and ice.
liquida state of matter, neither gas nor solid, that flows and takes the shape of its container.
critical flowThe flow regime at a given discharge for which the specific energy (i.e., combination of velocity energy and depth) are a minimum (Froude number = 1)
contact loadSediment particles that roll or slide along in almost continuous contact with the streambed (bed load).
gabionA wire basket or cage that is filled with gravel and generally used to stabilize stream banks and improve degraded aquatic habitat.
distillationwater treatment method where water is boiled to steam and condensd in a separate reservoir
loticMeaning or regarding things in running water.
underdraina concealed drain with openings through which the water enters when the water table reaches the level of the drain.
percolationthe movement of water through the subsurface soil layers, usually continuing downward to the groundwater or water table reservoirs.
sanitary landfilllandfill that is lined with plastic or concrete or located in clay-rich soils to prevent hazardous substances from leaking into the environment.
countermeasureMeasure intended to prevent, delay or reduce the severity of hydraulic problems.
accuracy"The closeness of the agreement between the result of a measurement and the value of the quantity being measured and or ""true value."" Usually expressed as ± a certain number of degrees or ± a certain percentage of the full reading."
ecological water requirementsThe water regimes needed to maintain ecological values of water dependent ecosystems at a low level of risk
drawdownLowering of the water table, surface water, or piezometric surface resulting from the withdrawal of water from a well or drain; the elevation of the static water level (at the well) at a given discharge.
restorationThe renewing or repairing of a natural system so that its functions and qualities are comparable to its original, unaltered state.
groundwater hydrologythe branch of hydrology that deals with groundwater; its occurrence and movements, its replenishment and depletion, the properties of rocks that control groundwater movement and storage, and the methods of investigation and utilization of ground water.
armorSurfacing of channel bed, banks, or embankment slope to resist erosion and scour
depletion curvein hydraulics, a graphical representation of water depletion from storage stream channels, surface soil, and groundwater
triple pointThe point at which any three atmospheric boundaries meet
buffer zoneThe band of vegetation that can reduce the amount of runoff entering a stream and provide vegetative corridors for the terrestrial life stages of aquatic organisms
macroinvertebratesMacroinvertebrates are aquatic animals without backbones that are large enough to be seen with the naked eye
holding ponda small basin or pond designed to hold sediment laden or contaminated water until it can be treated to meet water quality standards or be used in some other way.
backscatterA radar echo that is reflected, or scattered, at 180 degrees to the direction of the incident wave
hydraulic radiusCross‑sectional area of a stream divided by its wetted perimeter.
aeration tanka chamber used to inject air into water.
environmental impact statementa document that analyzes the effects of major federal projects on the environment
capillary forcesforces that cause ground water to rise above the surface of the saturated zone into the spaces between soil particles in the unsaturated zone.
snow depthThe actual depth of snow on the ground at any instant during a storm, or after any single snowstorm or series of storms.
bioaccumulationA term used to describe a process that occurs when levels of toxic substances increase in an organism over time, due to continued exposure.
undercuttingThe process by which the lower portion or "toe" of the streambank is eaten away by erosion leaving a concave, overhanging section of stream bank
instrument shelterA boxlike structure designed to protect temperature measuring instruments from exposure to direct sunshine, precipitation, and condensation, while at the same time time providing adequate ventilation.
chlorine contact chamberthe part of a wastewater treatment plant where treated water is disinfected by chlorine.
d-valueThe deviation of actual altitude along a constant pressure surface from the standard atmosphere altitude of that surface.
rechargeWater infiltrating to replenish an aquifer.
evaporationThe physical process by which a liquid, such as water is transformed into a gaseous state, such as water vapor
ground wateror aquifer, storage from surface water       supplies such as irrigation water, reclaimed wastewater or induced infiltration from streams       or wells.
wall cloudAn abrupt lowering of a cloud from its parent cloud base, a cumulonimbus or supercell, with no visible precipitation underneath
piercerspredators that feed by sucking fluids out of their prey
wave attackImpact of waves on a stream bank.
tributaryA stream that contributes its water to another stream or body of water.
instream useuse of water that does not require withdrawal or diversion from its natural watercourse; for example, the use of water for navigation, recreation, and support of fish and wildlife.
denitrificationThe reduction of nitrate or nitrite to nitrogen gas, in the absence of oxygen (ARMCANZ & ANZECC 2000).
normal stageWater stage prevailing during the greater part of the year.
mesocycloneA area of rotation of storm size that may often be found on the southwest part of a supercell
canopythe overhanging cover formed by branches and foliage.
cold air funnelFunnel clouds, usually short-lived, that develop from relatively small showers or thunderstorms when the air aloft is very in cold
precipitationrain, snow, hail, or sleet falling to the ground
thermoclineA vertical negative temperature gradient in some layer of a body of water which is appreciably greater than the gradients above and below it
instream flowsSee flows.
saltationParticles bouncing down a river bed
puddlea small pool of water, usually a few inches in depth and from several inches to several feet in its greatest dimension.
windwardThe direction from which the wind is blowing
landfallThe point at which a tropical cyclone's eye first crosses a land mass.
flash floodA sudden flood of great volume, usually caused by a heavy rain
intermountain highAn area of high pressure that occurs during the winter between the Rocky Mountains and the Sierra-Cascade ranges
die-backLoss of biodiversity due to environmental pressures such as weed invasion, nutrient-laden run-off or sedimentation.
rechargeThe processes involved in the addition of water to the zone of saturation; also the amount of water added.
supercritical watera type of thermal treatment using moderate temperatures and high pressures to enhance the ability of water to break down large organic molecules into smaller, less toxic ones
moistureRefers to the water vapor content in the atmosphere, or the total water, liquid, solid or vapor, in a given volume of air.
eddy currentA circular current of water, usually resulting from an obstruction, that develops when the main flow becomes separated from the bank.
oxygen demanding wasteorganic water pollutants that are usually degraded by bacteria if there is sufficient dissolved oxygen (DO) in the water.
siltTiny pieces of sand or rocks
phreatic lineUpper boundary of the seepage water surface landward of a streambank.
effluent limitationrestrictions established by a a regulating agency such as a State or the EPA in an NPDES permit on quantities, rates, and concentrations in wastewater discharges.
hydrologyThe study of the distribution and movement of water.
hardpointStreambank protection structure whereby "soft" or erodible materials are removed from a bank and replaced by stone or compacted clay
impoundmentA body of water, such as a pond, lake or reservoir, formed by confining a stream or other surface flow.
boundary conditionsdefinition or statement of conditions or phenomena at the boundaries of a model; water levels, flows, and concentrations that are specified at the boundaries of the area being modeled.
hudson bay lowAn area of low pressure over or near the Hudson Bay area of Canada that often introduces cold air to the north central and northeast United States.
tuberculationdevelopment or formation of small mounds of corrosion products on the inside of iron pipe
baseflowThe underlying flow rate that cannot be directly attributed to storm events (ARMCANZ & ANZECC 2000)
decompositionThe breakdown of matter by bacteria and fungi, changing the chemical makeup and physical appearance of materials.
wasatch windsStrong winds blowing easterly out of the Wasatch Mountains in Utah, sometimes reaching speeds greater than 75 miles per hour.
escarpmentthe topographic expression of a fault.
dissolved oxygenThe amount of free (not chemically combined) oxygen dissolved in water, wastewater, or other liquid, usually expressed in milligrams per liter, parts per million, or percent of saturation.
eutrophichaving a large or excessive supply of plant nutrients (nitrates and phosphates)
threatAn activity or land use with potential to damage the local or receiving environment's social/cultural, ecological or economic values.
active storage capacityThe total usable storage capacity available for seasonal or cyclic water storage
decomposable wastewaste that under suitable natural conditions can be transformed through biological and chemical processes into compounds that do not impair water quality.
threshold pollutantsubstance that is harmful to a particular organism only above a certain concentration, or threshold level.
continental shelfThe zone around the continents extending from the low-water mark seaward, typically ending in steep slope to the depths of the ocean floor.
siltationthe deposition or accumulation of fine soil particles.
bacteriaplants and animals.
hydrologic regimeA description of the variation of flow rate or water level over time.
geomorphologyA branch of both physiography and geology that deals with the form of the earth, the general configuration of its surface, and the changes that take place due to erosion of the primary elements and the buildup of erosional debris.
baseaccept 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).
floodplainarea along a stream or river subject to flooding; often the location of human development
riffleA reach of stream that is characterised by shallow, fast-moving water broken by the presence of rocks and boulders.
type kA common thermocouple sensor pairing two wires made mostly of nickel and chromium and using variance in voltage to calculate temperatures—known for its wide temperature range and affordability—typical in industrial applications.
erosionThe movement of soil or rock from one area to another by the action of the sea, running water, moving ice, precipitation, or wind.
equatorThe equator is an imaginary circle around the earth, halfway between the north and south poles.
canopyA layer of continuous foliage in a forest stand
emissivityA measure of the energy-emitting propensity of a surface, usually measured at a specific wavelength
nutrient recyclingThe process of nutrients being passed between biosphere and atmosphere.
advanced wastewater treatmentany treatment of sewage that goes beyond the secondary or biological water treatment stage and includes the removal of nutrients such as phosphorus and nitrogen and a high percentage of suspended solids.
eddy viscositya model parameter that reproduces the effects of turbulent mixing in fluid flow.
base flowThe sustained low flow of a stream, usually resulting from groundwater inflow to the stream channel rather than surface water run-off.
refluximplies that a solution/solvent is heated to a boil while maintaining its volume constant
phmeasure of the hydrogen ion activity; measures the acidity or alkalinity of a solution: the pH scale ranges from 1 (strong add) to 14 (strong base), with 7.0 as neutral
smokeSmall particles produced by combustion that are suspended in the air
sustainable managementmethod of exploiting a resource that can be carried on indefinitely
dama structure of earth, rock, or concrete designed to form a basin and hold water back to make a pond, lake, or reservoir.
trophic compositionthat portion of an Index of Biotic Integrity that is a metric measuring the proportion of species and proportions of omnivores, insectivores, and omnivores.
initial dilutionthe process that results in the rapid and irreversible turbulent mixing of effluent and receiving water around the point of discharge.
rapid drawdownLowering the elevation of water against a bank faster than the bank can drain, leaving a pressure imbalance that may cause the bank to fail.
snagAny standing dead, partially dead, or defective (cull) tree at least 10 in
mahdElevation in metres according to Australian Height Datum.
ecotonea transition zone between two distinctly different ecosystems or communities.
chokeRefers to the `Barmah Choke'
nutrientsEssential chemicals such as nitrogen (N) and phosphorus (P) needed by plants and animals for growth
channel storageSimply water storage within the banks of the channel.
nutrientsNutrients include several naturally occurring chemicals that animals and plants need to grow
rtdResistance Thermometer Detection probes use variance in resistance (typically in platinum) to calculate temperatures—known for high accuracy over a wide range of temperatures and low drift—typical in high-precision applications like calibration.
black iceThin, new ice on fresh or salt water that appears dark in color because of its transparency
adhesionthe molecular attraction asserted between the surfaces of bodies in contact
ecosystem managementA strategy or plan to manage ecosystems to provide for all associated organisms, as opposed to a strategy or plan for managing individual species.
lakeor other body of water into which light can penetrate, also       known as the zone of photosynthesis.
natural leveeLow ridge that slopes gently away from the channel banks that is formed along streambanks during floods by deposition.
conjunctive managementintegrated management and use of two or more water resources, such as an aquifer and a surface water body.
migrationChange in position of a channel by lateral erosion of one bank and simultaneous accretion of the opposite bank.
plungeSee Leap.
hydrometeran instrument used to measure the density of a liquid.
mouthThe point where a stream ends as it flows into another stream, or body of water.
terrestrial radiationLong wave radiation that is emitted by the earth back into the atmosphere
culvertA pipe that carries a stream from one above-ground section to another above-ground section
habitatThe native environment where a plant or animal naturally grows or lives.
zone of aerationa region in the Earth above the water table
phA measure of the acidity or alkalinity of a substance, using numerical values from 0 (maximum acidity) through 7 (neutral) to 14 (maximum alkalinity).
flow augmentationthe addition of water to meet flow needs.
thermoclinefairly thin zone in a lake that separates an upper warmer zone (epilimnion) from a lower colder zone (hypolimnion).
cold advectionThe horizontal movement of colder air into a location
perched water tablegroundwater standing unprotected over a confined zone.
drainageAn area (basin) mostly bounded by ridges or other similar topographic features, encompassing part, most, or all of a watershed and enclosing some 5,000 acres.
biomasterAn anti-microbial additive to the plastic housing of some ThermoWorks products containing silver ions shown to actively inhibit bacterial growth up to 99.9% over the life of the instrument
basina bowl shaped land formation usually caused by a glacier
stormwater dischargeprecipitation that does not infiltrate into the ground or evaporate due to impervious land surfaces but instead flows onto adjacent land or water areas and is routed into drain/sewer systems.
appropriative rights"first in time, first in right” principle of allocating water rights based
hydraulic modelSmall‑scale physical or mathematical representation of a flow situation.
clean water actfederal legislation enacted in 1972 to restore and maintain the chemical, physical and biological integrity of the surface waters of the United States
photosphereThe intensely bright portion of the sun visible to the unaided eye; the "surface" of the sun
stream gageA device used to measure the water surface elevation in relation to an established datum.
irrigation return flowwater which is not consumptively used by plants and returns to a surface or ground water supply
circulation cellsLarge areas of air movement created by the rotation of the earth and the transfer of heat from the equator toward the poles
currentWater flowing through a channel.
turbiditydegree to which light penetration is blocked because water is cloudy; measure of sediment suspended in water
kelvinAn absolute, thermodynamic temperature scale using as its null point absolute zero and the triple point of water at 273.16 K (0.01 °C; 32.02 °F)
bank-full channel depththe maximum depth of a channel within a rifle segment when flowing at a bank-full discharge.
sewageThe waste and wastewater produced by residential and commercial establishments and discharged into sewers.
driftThe change in the readings or measurement values of an instrument at a set point over time
soil erosionthe processes by which soil is removed from one place by forces such as wind, water, waves, glaciers, and construction activity and eventually deposited at some new place.
tertiary treatmentThe treatment of wastewater beyond the secondary or biological stage
soundingA plot of the atmosphere, using data rom upper air or radiosonde observations
inflowWater that flows into a reservoir or forebay during a specified period.
profilerA type of Doppler radar that typically measures both wind speed and direction from the surface to 55,000 feet in the atmosphere.
oceanAn ocean is a large body of salt water that surrounds a continent
elevationThe measure of height with respect to a point on the earth's surface above mean sea level
washout(1) Erosion of a relatively soft surface, such as a roadbed, by a sudden gush of water, as from a downpour or floods
channelA channel is an area that contains flowing water confined by banks.
saline waterwater containing more than 1,000 parts per million (ppm) of dissolved solids of any type
asymmetricalnot symmetrical
macrointervebratean animal without a backbone, large enough to be seen without magnification and unable to pass through a 0.595 mm mesh.
snowprecipitation in the form of branched hexagonal crystals, often mixed with simple ice crystals, which fall more or less continuously from a solid cloud sheet
cliffA very steep slope of rock or soil.
aquatic habitatHabitat that occurs in free water.
augmentationIncreasing stream flow under normal conditions, by releasing storage water from reservoirs.
ephemeral streamsStreams which flow only in direct response to precipitation and whose channel is at all times above the water table.
aerobic treatmentprocess by which microbes decompose complex organic compounds in the presence of oxygen and use the liberated energy for reproduction and growth
newtonThe unit of force giving a mass of about one kilogram (2.205 pounds) an acceleration of about one meter (1 yard) per second per second.
anvilThe upper portion of a cumulonimbus cloud that becomes flat and spread-out, sometimes for hundreds of miles downstream from the parent cloud
estuarineRefers to the water quality of an estuary, being influenced by both salt and fresh water.
woody debrisGenerally referring to naturally occurring wood in streams.
natural flowThe flow past a specified point on a natural stream that is unaffected by stream diversion, storage, import, export, return flow, or change in use caused by modifications in land use.
communitythe plants and animals that interact in a habitat; the community of people who influence a habitat
heterogeneityDiversity
rotationThe spinning of a body, such as the earth, about its axis.
scenic riversRivers or sections of rivers that are free of impoundments, with shoreline and watersheds still largely primitive, and shorelines largely undeveloped, but accessible in places by roads.
outwasha deposit of sand and gravel formed by streams of meltwater flowing from a glacier.
cascadingWhen a stream descends a very steep rock face somewhat smoothly or in a series of small individual drops, or any combination of these.
fluvialRelating to a stream or river; produced by stream action.
naturalized conditionsan estimate of natural conditions obtained by attempting to remove effects of human activities from a set of measured conditions.
siltSilt is very tiny particles of soil or rocks that are 3 to 60 micrometers in diameter.
hydraulicsThe study of the properties, movement and behavior of water flowing in open channels or pipes.
gravelrock 0.5 to 7 cm (0.2 to 3 inches) in diameter
baseline monitoringDevelopment of a system for continuous or periodic assessment, and recording of existing conditions that will be compared to future observations.
resolutionThe smallest detectable increment of measurement on an instrument
cliffA cliff is a steep face of rock and soil.
infiltrationThe movement of water into soil or porous rock
spawningbehavior and actions of male and female animals for the purposes of reproduction
aggradationa progressive build up of a channel bed with sediment over several years due to a normal sequence of scour and deposition, as distinguished from the rise and fall of the channel bed during a single flood.
backfillMaterial used to refill a ditch or other excavation, or the process of doing so.
green flashA brilliant green coloration of the upper edge of the sun, occasionally seen as the sun's apparent disk is about to set below a clear horizon.
enantiomeris a molecule that is not superimposable on its mirror image, related to chirality
toxicity testthe means to determine the toxicity of a chemical or an effluent using living organisms
water pollutionGenerally, the presence in water of enough harmful or objectionable material to damage the water's quality.
volatile organic compounesa group of chemicals that react in the atmosphere with nitrogen oxides, heat and sunlight to form ozone; VOCs are referred to as hydrocarbons.
sustainabilitythe long-term capacity of an ecosystem to maintain ecological processes and functions, biological diversity, and productivity.
invertebratesanimals without backbones including zooplankton, shellfish, worms, insects, shrimp, crabs and snails.
equilibrium scourScour depth in sand-bed stream with dune bed about which live bed pier scour level fluctuates due to variability in bed material transport in the approach flow.
sublimationthe transition of water directly from the solid state to the gaseous state, without passing through the liquid state; or vice versa
engulferspredators that eat their prey whole
spring melt/thawthe process whereby warm temperatures melt winter snow and ice
haboobSudanese name for duststorm or sandstorm with strong winds that carry small particles of dirt or sand into the air, particularly severe in areas of drought.
inert wastewaste that does not contain hazardous waste or soluble pollutants at concentrations in excess of applicable water quality objectives, and does not contain significant quantities of decomposable waste.
stream bankThe side slopes of an active channel between which the streamflow is normally confined.
wind waveAn ocean or lake wave resulting from the action of wind on the water's surface
weatheringThe decay and breakup of rocks on the earth's surface by natural chemical and mechanical processes
groundwaterWater that soaks into the soil and then flows within the matrix of soil or rock particles. 
fryA recently hatched fish.
brokenThe amount of sky cover for a cloud layer between 5/8ths and 7/8ths, based on the summation layer amount for that layer.
watershedA watershed is the term given to the land that drains water into a particular stream, lake, or river.
whiteoutWhen visibility is near zero due to blizzard conditions or occurs on sunless days when clouds and surface snow seem to blend, erasing the horizon and creating a completely white vista.
salmonellaA rod-shaped bacteria common to food, particularly chicken and chicken products like eggs
municipal dischargedischarge of effluent from treatment plants that receive wastewater from households, commercial establishments, and industries.
swampa type of wetland dominated by woody vegetation but without appreciable peat deposits
rain forestA forest which grows in a region of heavy annual precipitation
river stageThe elevation of the water surface at a specified station above some arbitrary zero datum (level).
flowThe amount of water passing a particular point in a stream or river, usually expressed in cubic-feet per second (cfs).
leachingextraction 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 groundwater.
embankmentAn artificial deposit of material that is raised above the natural surface of the land and used to contain, divert, or store water, support roads or railways, or for other similar purposes.
hard waterwater containing a high level of calcium, magnesium, and other minerals
psychrometerAn instrument used to measure water vapor content of the atmosphere
ecoregionA region defined by similarity of climate, landform, soil, natural vegetation, hydrology or other relevant variables.
hydrologic modela computer model of a watershed used to evaluate how precipitation contributes to flow in streams
hydrographa chart that measures the amount of water flowing past a point as a function of time.
sandSmall substrate particles, generally from 0.6 to 2.0 mm in diameter
advisoryStatements that are issued by the National Weather Service for probable weather situations of inconvenience that do not carry the danger of warning criteria, but, if not observed, could lead to hazardous situations
transparentA condition where a material is clear enough not to block the passage of radiant energy, especially light.
blackwaterwastewater from toilet, latrine, and agua privy flushing and sinks used for food preparation or disposal of chemical or chemical-biological ingredients.
capComposed of a layer of warmer, dryer air aloft which may suppress or delay the development of thunderstorms
critical habitatUnder the Endangered Species Act, critical habitat is defined as(1) the specific areas within a geographic area occupied by a federally listed species on which are found physical and biological features essential to the conservation of the species, and that may require special management considerations or protections; and (2) specific areas outside the geographic area occupied by a listed species, when it is determined that such areas are essential for the conservation of the species.
rockA naturally formed mass of minerals.
thermal plantA power plant that produces electricity from heat energy released by the combustion of a fossil fuel (coal, oil, or gas) or the consumption of a fissionable material (nuclear fuel).
mean column velocitythe average velocity of fluid flow measured in a column extending from the surface of the water to the bed of the channel
stageThe height of water above an established datum
extractionwater taken from rivers for off stream use or consumption
particulatesthe 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.
trickling filtera treatment system in which wastewater is trickled over a bed of stones or other material covered with bacteria that break down the organic waste and produce clean water.
bank slumpingAn indication of the degree of bank erosion
armoringNatural armoring is the formation of a resistant layer of relatively large particles resulting from removal of finer particles by erosion
environmental analysisAn analysis of alternative actions and their predictable short-term and long-term environmental effects, incorporating physical, biological, economic, and social considerations.
entrenchment ratioThe ratio between the flood-prone width and the bankfull width.
goals or aimsGeneral descriptions of what a project will achieve (Woodhill & Robins 1998).
fillSoil or other material placed as part of a construction activity
estuarine zonearea near the coastline that consists of estuaries and coastal saltwater wetlands.
mortalitydeath
leachingThe removal of soluble organic and inorganic substances from the topsoil downward by the action of percolating water.
injection zonea geological formation receiving fluids through a well.
influentwater, wastewater, or other liquid flowing into a reservoir, basin, or treatment plant.
zooplanktontiny aquatic animals eaten by fish.
off-site enhancementThe improvement in conditions for fish and wildlife species away from the site or development activities that may have detrimental effects on fish and/or wildlife, as part or total compensation for those effects.
enteric virusesa category of viruses related to human excreta found in waterways.
hardpana shallow layer of earth material which has become relatively hard and impermeable, usually through the deposition of minerals
le châtelier principledescribes equilibrium reactions and how to influence them
angle of reposeThe maximum slope at which unconsolidated material remains stable.
time of concentrationThe time required for water to flow from the farthest point in the watershed to the gaging station.
heat balanceThe equilibrium which exists on the average between the radiation received by the earth and atmosphere from the sun and that emitted by the earth and atmosphere
check dama small dam constructed in a gully or other small water course to decrease the streamflow velocity, minimize channel erosion, promote deposition of sediment and to divert water from a channel.
in-line filtrationa pretreatment method in which chemicals are mixed by flowing water; commonly used in pressure filtration installations.
biodiversityRefers to variety of organisms, their genetic information and the biological communities where they live.
floodplainland next to a river that becomes covered by water when the river overflows its banks .
contaminantA substance that presents or has the potential to present a risk of harm to human health, the environment or any environmental value .
meanderA bend in a river - usually in the middle or lower course
kilowattA unit of electrical power equal to 1000 watts or 1.341 horsepower.
sleetAlso known as ice pellets, it is winter precipitation in the form of small bits or pellets of ice that rebound after striking the ground or any other hard surface
evaporationthe change by which any substance is converted from a liquid state and carried of in vapor
ravineA steep sided depression cut by a stream, smaller than a valley and larger than a gully.
meander lengthThe lineal distance downvalley between two corresponding points of successive meanders of the same phase.
parallelAnother word for latitude lines.
loadAmount of sediment being moved by a stream.
local scourRemoval of material from around piers, abutments, spurs, and embankments caused by an acceleration of flow and resulting vortices induced by obstructions to the flow.
physical weatheringbreaking down of parent rock into bits and pieces by exposure to temperature and changes and the physical action of moving ice and water, growing roots, and human activities such as farming and construction
codChemical Oxygen Demand.  A measure of the oxygen equivalent of the organic matter content of a sample that is susceptible to oxidation by a strong chemical oxidation.  Differs from the BOD test in that COD uses oxygen derived from chemicals, while BOD uses oxygen derived from air dissolved in water. 
confluenceJunction of two or more streams.
quarry waterthe moisture content of freshly quarried stone, esp
runoffThat portion of total rainfall that eventually enters a river
hurricane watchA formal advisory issued by forecasters at the National Hurricane Center when they have determined that hurricane conditions are a potential threat to a coastal area or group of islands within a 24 to 36 hour period
recrystallizationis a technique used to purify solids based on different solubilities of the impurity and the target compound.
minimum operations guideThe system minimum operations guide is a seasonal guide based on the sum of the storage in 10 tributary projects
tropic of cancerThe most northern point on the earth where the sun is directly overhead, located at approximately 23.5 degrees North latitude.
duststormA severe weather condition characterized by strong winds and dust-filled air over a large area
regulatorsStructural works that control flow.
biomassThe amount of living matter, usually given in weight per unit area of habitat.
comma cloudA feature seen on satellite images with a distinctive comma-shape
prior appropriationa doctrine of water law that allocates the rights to use water on a first in time, first in right, basis.
hurricane warningA formal advisory issued by forecasters at the National Hurricane Center when they have determined that hurricane conditions are expected in a coastal area or group of islands within a 24 hour period
effluent streamA stream that takes source water from the water table.
surface runoffSurface runoff is water flow on the land that occurs when the soil is saturated with water and the excess water (from precipitation or snowmelt) runs over the surface.
headworksStructural works designed to induce a pressure gradient or move water in a particular way
samplebacterial       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.
zone of saturationthe space below the water table in which all the interstices (pore spaces) are filled with water
carbon adsorptiona treatment system that removes contaminants from ground water or surface water by forcing it through tanks containing activated carbon treated to attract the contaminants.
hydrostatic heada measure of pressure at a given point in a liquid in terms of the vertical height of a column of the same liquid which would produce the same pressure.
check damLow dam or weir across a channel used to control stage or degradation.
scourThe erosive action of running water in streams, which excavates and carries away material from the bed and banks
nutrient depletionDetrimental changes at a site in the total amount of nutrients and/or their rates of input, uptake, release, movement, transformation, or export.
benthicassociated with the bottom of a water body
loadingThe influx of pollutants to a selected water body.
stoneRock fragments larger than 25.4 cm (10 inches) but less than 60.4 cm (24 inches).
chute spillwaythe overall structure which allows water to drop rapidly through an open channel without causing erosion
alevinnewly hatched fish with yolk sac attached, larva
densityThe ratio of the mass of a substance to the volume it occupies
furrow irrigationirrigation method in which water travels through the field by means of small channels between each group of rows.
eutrophic lakeShallow, murky bodies of water that have excessive concentrations of plant nutrients causing excessive algal production.
discount rateThe interest rate used in evaluating water (and other) projects to calculate the present value of future benefits and future costs or to convert benefits and costs to a common time basis.
connate waterwater trapped in the pore spaces of a sedimentary rock at the time it was deposited
standard surface pressureThe measurement of one atmosphere of pressure under standard conditions
salt water intrusionthe invasion of fresh surface or ground water by salt water
on-site sewage treatmentany individual residential sewage treatment and wastewater dispersal system, such as a septic system.
nonalluvial channelChannel whose boundary is in bedrock or non-erodible material.
recession curveThat part of a hydrograph after the flow peak showing decreasing runoff or discharge following a period of rain or snowmelt.
adsorb pollutantsused in some water       treatment systems to remove certain organic chemicals and radon gas.
planformThe shape of an object as viewed from above
degreeA unit of measurement of temperature on any of several scales, such as Celsius or Fahrenheit.
channelizationThe process of changing and straightening the natural path of a waterway.
dalton's lawStates that the total pressure exerted by a mixture of gases is equal to the sum of the partial pressures of the gases
embeddednessa measure of the degree that gravel and larger substrates are surrounded by fine particles (silt and sand).
condensationThe process by which water vapor undergoes a change in state from a gas to a liquid
mother liquorthe solution that was separated from the crystals
substrateThe composition of a streambed, including either mineral or organic materials.
flood-prone areaA term coined by Rosgen (1996) to describe the area flooded at flows twice the maximum depth of flow at the effective discharge.
finite differencea method of solving the governing equations of a numerical model by dividing the spatial domain into a mesh of nodes
poles/polarThe poles are the geographic point at 90 degrees latitude North and South on the earth's surface
oxbowAbandoned former meander loop that remains after a stream cuts a new, shorter channel across the narrow neck of a meander
satellite imagesImages taken by a weather satellite that reveal information, such as the flow of water vapor, the movement of frontal system, and the development of a tropical system
currentthe portion of a stream or body of water which is moving with a velocity much greater than the average of the rest of the water
kinetic energyenergy possessed by a moving object or water body.
sheet floodingRun-off or artificially induced run-off that flows over the ground surface as a thin, even layer not concentrated in a channel.
confining bed or unita body of impermeable or distinctly less permeable material stratigraphically adjacent to one or more aquifers.
hyporheic zonethe zone under a river or stream comprising substrate whose interstices are filled with water.
mariculturecultivation of fish and shellfish in estuarine and coastal areas
biological monitoringSampling the biota of a place (e.g., stream) repetitively to monitor change over time.
diversionto remove water from a water body
thermistorA common thermal sensor that uses the predictable variance in the resistance to an electrical current with changes in temperature to calculate temperatures
riparian area of influencetransition area between riparian area and upland vegetation
fabric mattressGrout-filled mattress used for streambank protection.
overland flowa land application technique that cleanses wastewater by allowing it to flow over a sloped surface
balancing guideThe elevation that is used to help maintain a relative balance among tributary storage reservoirs
showalter stability indexA measure of the local static stability of the atmosphere
septic tankunderground receptacle for wastewater from a home
hydropneumatica water delivery system, usually small, that maintains water pressure in the distribution system by means of pressure in a compressed air tank.
stationary frontA front which is nearly stationary or moves very little since the last synoptic position
trigger eventEnvironmental conditions (which may be flow or non-flow) that initiate an event
dykeAn artificial embankment constructed to prevent flooding.
diffractionThe result of light waves interfering with other after passing through a narrow aperture, causing them to bend or spread.
undercurrenta current below the upper currents or surface of a fluid body.
wetland specialistsRefers to flora or fauna who forage for food, recruit or carry out their life cycle within wetland habitats.
ice stormA severe weather condition characterized by falling freezing precipitation
suspended sedimentSediment suspended in a fluid by the upward components of turbulent currents, moving ice, or wind.
monitoringAssessing the short- or long-term and localised change in environmental or river condition as a result of specific actions.
pesticideA substance or mixture of substances intended for preventing, destroying, repelling, or mitigating any pest
jet streama long narrow meandering current of high-speed winds near the tropopause blowing from a generally westerly direction and often exceeding a speed of 250 miles per hour.
freezing drizzleDrizzle, falling as a liquid, but freezing on impact with the colder ground or other exposed surfaces
resistanceThe resistance to the flow of electric current measured in ohms
calorieIn meteorology, it is the amount of heat required to raise the temperature of one (1) gram of water one (1) degree Celsius
supercoolingThe reduction of the temperature of any liquid below the melting point of that substance's solid phase
wild riversRivers or sections of rivers that are free of impoundments and generally inaccessible except by trail, with watersheds or shorelines essentially primitive and water unpolluted.
cascadeThe sudden descent of a stream primarily over a very steep slope in its stream bed
contiguous habitatHabitat suitable to support the life needs of a species that is distributed continuously across the landscape.
mesohabitatbasic structural elements of a river or stream such as pools, backwaters, runs, glides, and riffles.
static water levelelevation or level of the water table in a well when the pump is not operating; the level or elevation to which water would rise in a tube connected to an artesian aquifer or basin in a conduit under pressure.
icicleIce that forms in the shape of a narrow cone hanging point down
attritionThe wearing away of particles of rock as they bounce along the riverbed or knock against each other and wear away becoming more rounded.
dinAn acronym for Deutsche Industrial Norm
drifting snowSnow particles blown from the ground by the wind to a height of less than six feet.
type jA specialized thermocouple sensor pairing two wires made mostly of iron and constantan and using variance in voltage to calculate temperatures—more limited in its range to higher temperatures but known for its sensitivity.
pool/riffle ratioThe ratio of surface area or length of pools to the surface area or length of riffles in a given stream reach; frequently expressed as a relative percentage of each category
pumped storage projectA hydroelectric power plant and reservoir system in which water released for generating energy during peak load periods is stored and pumped back into the upper reservoir, usually during periods of reduced power demand.
adiabatic processA thermodynamic change of state in a system in which there is no transfer of heat or mass across the boundaries of the system
aerationAny active or passive process by which intimate contact between air and liquid are assured, generally by spraying liquid in the air, bubbling air through water, or mechanical agitation of the liquid to promote surface absorption of air.
erosionDisplacement of soil particles due to water or wind action.
droughtAbnormal dry weather for a specific area that is sufficiently prolonged for the lack of water to cause serious hydrological imbalance.
anabranched streamStream whose flow is divided at normal and lower stages by large islands or, more rarely, by large bars; individual islands or bars are wider than about three times water width; channels are more widely and distinctly separated than in a braided stream.
deltaa collection of rocks and soil at the mouth of a river
gradientdegree of slope, or steepness of a geographic feature
droughtGenerally, the term is applied to periods of less than average or normal precipitation over a certain period of time sufficiently prolonged to cause a serious hydrological imbalance resulting in biological losses (impact flora and fauna ecosystems) and/or economic losses (affecting man)
alkalinethe condition of water or soil that contains a sufficient amount of alkali substance to raise the pH above 7.0.
streambank stabilizationNatural geological tendency for a stream to mold its banks to conform with the channel of least resistance to flow
rinsing/rinserefers to the washing of a solid with small amounts of cold solvent to remove mother liquor and impuries from the surface
invertebrate driftStream and terrestrial invertebrates that float with the current.
sublimationThe process of a solid (ice) changing directly into a gas (water vapor), or water vapor changing directly into ice, at the same temperature, without ever going through the liquid state (water)
groundwater rechargeIncreases in groundwater storage by natural conditions or by human activity
apronProtective material placed on a streambed to resist scour.
turbidityCloudiness caused by the presence of suspended sediments in water, typically measured with a Secchi disk or turbidity tube.
bed roughnessA measure of the irregularity of the streambed as it contributes to flow resistance
peaked stone dikeRiprap placed parallel to the toe of a streambank (at the natural angle of repose of the stone) to prevent erosion of the toe and induce sediment deposition behind the dike.
fena type of wetland that accumulates peat deposits, but not as much as a bog
braided streamStream whose flow is divided at normal stage by small mid‑channel bars or small islands; the individual width of bars and islands is less than about three times water width; a braided stream has the aspect of a single large channel within which are subordinate channels.
fluvial geomorphologyScience dealing with morphology (form) and dynamics of streams and rivers.
cotyledonThe `seed leaves' produced by the embryo of a seed plant that serve to absorb nutrients packaged in the seed, until the seedling is able to produce its first true leaves and begin photosynthesis
subsidencesinking down of part of the earth's crust due to underground excavation, such as removal groundwater.
well monitoringmeasurement by on-site instruments or laboratory methods of well water quality.
emergent plantsEmergent vegetation includes aquatic plants which have roots in the sediment of a stream but stems which extend through and above the water
imperviousthe quality or state of being impermeable; resisting penetration by water or plant roots
mistA collection of microscopic water droplets suspended in the atmosphere
altimeter settingThe pressure value to which an aircraft altimeter scale is set so that it will indicate the altitude above mean sea level of an aircraft on the ground at the location for which the value was determined.
bank revetmentErosion‑resistant materials placed directly on a streambank to protect the bank from erosion.
closed lowA region of low pressure distinguished by a center of counterclockwise circulation (in the Northern Hemisphere), and is surrounded by one or more isobars or height contours
crown coverThe degree to which the crowns of trees are nearing general contact with one another.
wetlandland inundated wish temporary or permanent water that is usually slow moving or station, shallow, and either fresh, brackish or saline.
sea mileA unit of length distinguished from a nautical mile
bedrockthe solid rock or geologic surface underlying unconsolidated surface materials (e.g., water, soil, alluvium).
clinometerAn instrument used to measure angles of inclination
wellhead protection areaa protected surface and subsurface zone surrounding a well or well field supplying a public water system to keep contaminants from reaching the well water.
entrenched channelA channel that has eroded downward or was constructed such that it no longer has access to its original floodplain during moderate flow events.
distance to target ratio"Indicates the diameter of the surface area an infrared thermometer will measure at a given distance
sludge digestertank in which complex organic substances like sewage sludge are biologically dredged
stream morphologyThe form and structure of streams.
reddShallow depression in the streambed gravel in which a female salmonid (e.g., trout) deposits her eggs
instream coverThe layers of vegetation, like trees, shrubs, and overhanging vegetation, that are in the stream or immediately adjacent to the wetted channel.
protozoansA single-celled organism.
enantiomeric excessis the ratio of one enantiomer to the other enantiomer in a mixture (abbreviated: e.e
tertiary treatmentIn sewage, the additional treatment of effluent beyond that of secondary treatment to obtain a very high quality of effluent for reuse.
flash floodA flood that rises and falls quite rapidly with little or no advance warning, usually as the result of intense rainfall over a relatively small area
chlorinationthe adding of chlorine to water or sewage for the purpose of disinfection or other biological or chemical results.
cobbleSubstrate particles that are smaller than boulders and larger than gravels, and are generally 64-256 mm in diameter
directional shearThe shear created by a rapid change in wind direction with height.
calorieamount of energy required to raise the temperature of 1 gram of water 1 degree Celsius.
aquiferAn underground layer of rock or soil containing ground water.
tailraceThe channel that is downstream of the draft tube that carries the water discharged from a turbine
drainage reusereuse of agricultural drainage on salt-tolerant crops.
groundwater rechargeWater that is returned to subsurface flow from surface flow.
hydrographA chart that measures the amount of water flowing past a point as a function of time.
armoringA natural or artificial process where an erosion-resistant layer of relatively large particles is established on the surface of the streambed through the removal of finer particles by stream flow
method blanklaboratory grade water taken through the entire analytical procedure to determine if samples are being accidentally contaminated by chemicals in the lab
urbanLand used for residential, rural-residential, commercial or industrial development (includes regional towns).
tropic of capricornThe most southern point on the earth where the sun is directly overhead, located at approximately 23.5 degrees South latitude.
southern oscillationA periodic reversal of the pressure pattern across the tropical Pacific Ocean during El NiÑo events
permeabilityThe capability of soil or other geologic formations to transmit water.
sediment loadThe soil particles transported through a channel by stream flow.
calibrationto check, adjust, or determine by comparison that a computer model will produce results that meet or exceed some defined criteria within a specified degree of confidence.
trunkThe trunk is the main course of river.
critical habitatAreas containing physical and biological features essential to the conservation of a species, and that may require special management considerations or protections.
key habitatsflow-sensitive habitats as well as habitats that support key species.
concrete revetmentUnreinforced or reinforced concrete slabs placed on the channel bed or banks to protect it from erosion.
trickle irrigationmethod in which water drips to the soil from perforated tubes or emitters.
crestthe top of a dam, dike, or spillway, which water must reach before passing over the structure; the summit or highest point of a wave; the highest elevation reached by flood waters flowing in a channel.
zooplanktonfloating microscopic animals.
baselineEstablishing the current status of the system.
pluvialpertaining to precipitation.
dischargeVolume of water passing through a channel during a given time.
causewayRock or earth embankment carrying a roadway across water.
migrationthe movement of oil, gas, contaminants, water, or other liquids through porous and permeable rock.
planktonTiny plants and animals that live in water.
haccpAn acronym for Hazard Analysis Critical Control Point
eutrophicationThe process of enrichment of water bodies by nutrients.
meander ratioRatio of meander width to meander length.
water pollutiondegradation of a body of water by a substance or condition to such a degree that the water fails to meet specified standards or cannot be used for a specific purpose.
eutrophicationan excess of plant nutrients from natural erosion and runoff from the land in an aquatic ecosystem supporting a large amount of aquatic life that can deplete the oxygen supply.
critical low flowlow flow conditions below which some standards do not apply
bmpBest Management Practice
colloidsfinely divided solids which will not settle but which may be removed by coagulation or biochemical action.
depositsomething dropped or left behind by moving water, as sand or mud.
aerobicCharacterizing organisms able to live only in the presence of air or free oxygen, and conditions that exist only in the presence of air or free oxygen
meander beltDistance between lines drawn tangent to the extreme limits of successive fully developed meanders.
opaqueA condition where a material, such as a cloud, blocks the passage of radiant energy, especially light
aerationAny active or passive process by which intimate contact between air and liquid is assured, generally by spraying liquid in the air, bubbling air through water, or mechanical agitation of the liquid to promote surface absorption of air.
adjudicationa court proceeding to determine all rights to the use of water on a particular stream system or ground water basin.
vapor trailA cloudlike streamer or trail often seen behind aircraft flying in clear, cold, humid air
listeriaA rod-shaped bacteria common to food.
cement grouta mixture of water and cement in the ratio of not more than 5-6 gallons of water to a 94 pound sack of portland cement which is fluid enough to be pumped through a small diameter pipe.
risk assessmentThe process of risk analysis and risk evaluation.
squall lineA narrow band or line of active thunderstorms that is not associated with a cold front
salt waterThe water of the ocean, distinguished from fresh water by its appreciable salinity.
detritusdecaying organic matter (mostly leaves and other matter from vegetation).
slope stabilityThe resistance of a natural or artificial slope or other inclined surface to failure by mass movement.
flow-sensitive habitatshabitats that show hydraulic response to relatively small changes in streamflow
oceanlake, or other body of water into which light can penetrate, also       known as the zone of photosynthesis.
day-second-feetA measure of the volume of water accumulated at a flow rate of one cubic foot per second running for one day
surchargingIn this case, refers to the filling of groundwater, surface water or a structural feature such as a dam.
rain gaugeAn instrument used to measure the amount of rain that has fallen
coupling constantcharacterizes the line spacing within a multiplet in a 1H-NMR spectrum, which permits conclusions about the distance and the angle of interaction of the coupling partners
snowburnA burn of the skin, like a sunburn, but caused by the sun's rays reflected off the snow surface.
background noiseThe total noise floor from all sources of interference in a measurement system, independent of the presence of a data signal.
recruitmentIncrement to a natural population, usually from young animals or plants entering the adult population.
hydrologyThe scientific study of the water of the earth, its occurrence, circulation and distribution, its chemical and physical properties, and its interaction with its environment, including its relationship to living things.
hydrographA graph showing flow, stage, velocity or discharge with respect to time, for a given point in the stream.
plate tectonicsrefers to the folding and faulting of rock and flow of molten lava involving lithospheric plates in the earth's crust and upper mantle.
radiationThe process by which energy is propagated through any medium by virtue of the wave motion of that medium
dynamic equilibriumThe state at which the channel exhibits patterns of erosion and deposition but there is not net change in the input and output of materials
stream gradientA general slope or rate of change in vertical elevation per unit of horizontal distance of the water surface of a flowing stream.
dilution ratiothe critical low flow of the receiving water at the point of recycled water discharge divided by the flow of the discharge.  Is used in the biomonitoring test to simulate in-stream conditions that organisms will be exposed to during critical low-flow times.
draftthe act of drawing or removing water from a tank, reservoir or groundwater supply.
dischargerany person who discharges waste that could affect the quality of state waters
whitewaterSwift moving water, whose surface has become foamy and turbulent because of passing over or around rocks.
revetmentA facing of stone, rootwads, cut trees, or other durable material used to protect a streambank against erosion.
run-of-river reservoirA project that relies on the flow of a stream or river to produce hydropower but has little or no capacity to store water
biotaThe flora/plants and fauna/animals of an area.
mare's tailThe name given to thin, wispy cirrus clouds composed of ice crystals that appear as veil patches or strands, often resembling a horse's tail.
nondegradationan environmental policy that does not allow any lowering of naturally occurring water quality regardless of pre-established health standards.
gale warningA warning for marine interests for impending winds from 28 to 47 knots (32 to 54 miles per hour).
vanesAn artificial structure used to direct flows in a stream.
pipingRemoval of soil material through subsurface flow of seepage water that develops channels or "pipes" within the soil bank.
microbarographA instrument designed to continuously record a barometer's reading of very small changes in atmospheric pressure.
tideThe periodic rising and falling of the earth's oceans and atmosphere
pollutant retentionThe proportion of pollutant load intercepted and retained by a device, either on an event or annual basis (ARMCANZ & ANZECC 2000).
canyonwalls of rock along a river, sometimes very steep
restorationThe return of an ecosystem to a close approximation of its condition prior to disturbance.
rain rejection eventsSee rain rejection.
multiple use corridorsFacilities performing a range of functions (e.g
connectivityRefers to the water-mediated transfer of matter, energy and organisms between elements of the hydrologic cycle eg
base levelThe elevation to which a stream-channel profile has developed.
plumethe area taken up by contaminant(s) in an aquifer.
aerationThe mixing of air and water, usually by bubbling air through water or by contact of water with air.
setbackDenotes the positioning of a levee or structure in relationship to a stream bank
suspended sedimentRefers to small solid particles which remain in suspension in the water column and cause poor water clarity. 
wildlife treeA live tree retained to become future snag habitat.
blooma proliferation of algae and/or higher aquatic plants in a body of water; often related to pollution or excessive nutrients, especially when they accelerate growth.
tailings pondAn excavated or diked area that is intended to contain liquid and solid wastes from mining and milling operations.
ecological valuesParticular values or uses of the environment important for a healthy ecosystem or for public benefit, welfare, safety or health and economic activities, and which require protection from the effects of pollution, waste discharges and deposits (ARMCANZ & ANZECC 2000) and from the effects of altered water regimes.
uncertaintyAn expression of the possible measurement error for a given instrument over a specified range
vapor plumesflue gases that are visible because they contain water droplets.
constantanA copper-nickel alloy used as the negative lead in Type E, Type J, and Type T thermocouples.
talusA chaotic accumulation of large rocks at the base of a cliff or steep slope.
chlorine demandthe difference between the amount of chlorine added to water, sewage, or industrial wastes and the amount of residual chlorine remaining at the end of a specific contact period
immiscibilitythe inability of two or more substances or liquids to readily dissolve into one another, such as soil and water.
forebayA reservoir or pond situated at the intake of a pumping plant or power plant to stabilize water levels; also, a storage basin for regulating water for percolation into groundwater basins.
perennial yieldThe maximum quantity of water that can be annually withdrawn from a groundwater basin over a long period of time (during which water supply conditions approximate average conditions) without developing an overdraft condition
indicator organismsmicroorganisms, such as coliforms, whose presence is indicative of pollution or of more harmful microorganism.
environmental outcomesProject outcomes that benefit the ecological health of the river system.
radionuclidea radioactive particle, man-made or natural, with a distinct atomic weight number
baseflowThe sustained portion of stream discharge that is drawn from natural storage sources, and not affected by human activity or regulation.
translucent floodFlow that is allowed to spill over a dam wall, not necessarily as a result of exceeding the height of the dam.
base flowThe sustained portion of stream discharge that is drawn from natural storage sources, and not effected by human activity or regulation.
mean annual dischargeDaily mean discharge averaged over a period of years
caverna large underground opening in rock (usually limestone) which occurred when some of the rock was dissolved by water
live-bed scourScour at a pier or abutment (or contraction scour) when the bed material in the channel upstream of the bridge is moving at the flow causing bridge scour.
rifflerelatively fast flowing, shallow water in a stream
sedimentSolid fragment of organic and inorganic material that is transported, suspended and/or deposited by water and wind.
static water depththe vertical distance from the centerline of the pump discharge down to the surface level of the free pool while no water is being drawn from the pool or water table.
tube settlerdevice using bundles of tubes to let solids in water settle to the bottom for removal by conventional sludge collection means
ripple(1) To form or display little undulations or waves on the surface, as disturbed water does
streamA general term for a body of water flowing by gravity; natural watercourse containing water at least part of the year
range resolutionThe ability of radar to distinguish between targets on the same azimuth but at different ranges.
contact recreationactivities involving a significant risk of ingestion of water, such as wading by children, swimming, water skiing, diving and surfing
base flowthe water that flows in a river during the dry periods between rainstorms
landslideA movement of earth down a steep slope.
fetchArea in which waves are generated by wind having a rather constant direction and speed; sometimes used synonymously with fetch length.
adjustable emissivityA setting on many infrared thermometers allowing you to help the thermometer calculate a more accurate temperature reading for a given material based on an estimate of its ability to emit infrared energy
blue-green algaealso known as cyanobacteria
hydrosphereConsidered as the water portion of the earth's surface
rapidA reach of stream that is characterized by small falls and turbulent, high-velocity water.
vacuum filtrationis a filtration technique that permits to separate a solid from a liquid
abandoned water righta water right which was not put to beneficial use for a number of years, generally five to seven years.
aqueous solubilitythe maximum concentration of a chemical that will dissolve in pure water at a reference temperature.
toxic hot spotlocation in enclosed bay, estuary, or any adjacent waters that has toxic pollution problems in the water or sediment in excess of applicable standards.
landslidea movement of earth mass down a steep slope.
erosionmovement of soil by water and wind
bank-full widththe width of a river or stream channel between the highest banks on either side of a stream.
aggradationA progressive buildup or raising of the channel bed and floodplain due to sediment deposition
faceThe vertical surface of a waterfall found between its crest and its base.
tractive forceThe drag or shear stress on a stream bank or stream bed caused by passing water which tends to pull soil particles along with the stream flow.
shear lineA line of maximum horizontal wind shear
freeboardthe vertical distance between the lowest point along the top of a surface impoundment dike, berm, levee, treatment works or other similar feature and the surface of the liquid contained therein.
rearing pondAn artificial impoundment in which juvenile fish are raised prior to release into the natural habitat.
drainage basinArea confined by drainage divides, often having only one outlet for discharge (catchment, watershed).
filterLayer of fabric (geotextile) or granular material (sand, gravel, or graded rock) placed between bank revetment (or bed protection) and soil for the following purposes: (1) to prevent the soil from moving through the revetment by piping, extrusion, or erosion; (2) to prevent the revetment from sinking into the soil; and (3) to permit natural seepage from the streambank, thus preventing the buildup of excessive hydrostatic pressure.
background levelthe concentration of a substance in an environmental media (water or soil) that occurs naturally or is not the result of human activities.
eutrophicUsually refers to a nutrient-enriched, highly productive body of water.
artificial dischargeAddition of surface water to a groundwater reservoir by human activity, such as putting surface water into spreading basins
aerobic or oxic zoneAn environment in which there is free oxygen (ARMCANZ & ANZECC 2000).
auroraIt is created by the radiant energy emission from the sun and its interaction with the earth's upper atmosphere over the middle and high latitudes
mixed layerIt is the upper portion of the boundary layer in which air is thoroughly mixed by convection
dredgingremoval of mud from the bottom of water bodies
potable waterWater generally considered suitable for human consumption.
geographic information systemA computer system capable of storing and manipulating spatial data.
groundwaterGroundwater is water that percolates down the soil profile
condensationwater vapor that is forming droplets
best management practiceConservation measures intended to minimize or mitigate impacts from a variety of land-use activities.
nightThe period of the day between dusk and dawn.
soluble mineralsNaturally occurring substances capable of being dissolved.
channelizationnatural or intentional straightening and/or deepening of streams so water moves faster and causes less flooding.  Channelization can sometimes exacerbate flooding in other downstream areas.
flocculationlarge 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.
average velocityVelocity at a given cross section determined by dividing discharge by cross sectional area.
homogenous aquiferan aquifer that has similar forms or characteristics throughout, such as a uniform gravel aquifer
river milesMiles from the mouth of a river to a specific destination or, for upstream tributaries, from the confluence with the main river to a specific destination.
sewageThe liquid waste from domestic, commercial, and industrial establishments.
subwatershedA small area of a larger watershed for which surface runoff drains to a particular point
headthe pressure of a fluid owing to its elevation, usually expressed in feet of head or in pounds per square inch, since a measure of fluid pressure is the height of a fluid column above a given or known point.
confluence(1) The act of flowing together; the meeting or junction of two or more streams; also, the place where these streams meet
rifflesA river feature where below average depth and above average velocity create small cresting waves.
impermeablematerial that does not permit fluids to pass through.
spawningThe depositing and fertilizing of eggs (or roe) by fish and other aquatic life.
circulationThe flow or motion of a fluid in or through a given area or volume
cheyenne fogAn upslope fog formed by the westward flow of air from the Missouri River Valley, producing fog on the eastern slopes of the Rockies.
leachingThe flushing of minerals or pollutants from soil or other material by the percolation of applied water.
photosynthesismanufacture of carbohydrates by plants using energy from light.
visitor-daySee recreation-day.
outfallThe mouth or outlet of a river, stream, lake, drain or sewer.
charles' lawStates that when the pressure is held constant, the volume of a gas varies directly with the temperature
emulsionis a suspension of finely divided particles in a continuous medium in which the particles are approximately 5 to 5,000 Å in size, do not settle out of the substance rapidly, and are not readily filtered i.e
laminar flowStreamline or parallel flow near a solid boundary
geosphereConsidered the solid portions of the earth, including the hydrosphere and the lithosphere, as opposed to the atmosphere, which lies above it
gradientVertical drop per unit of horizontal distance.
snow blindnessTemporary blindness or impaired vision that results from bright sunlight reflected off the snow surface
gas chromatographan instrument that identifies the molecular composition and concentrations of various chemicals in water and soil samples.
hook echoA radar reflectivity pattern observed in a thunderstorm, appearing like a fish hook and indicating favorable conditions for tornadic development
entrainto trap bubbles in water either mechanically through turbulence or chemically through a reaction.
frosta covering of minute ice crystals on a cold surface.
fewThe amount of sky cover for a cloud layer between 1/8th and 2/8ths, based on the summation layer amount for that layer.
weira construction across a river that dams the water but may be removable during times of flood.
middensA mound of domestic refuse containing shells and animal bones marking the site of an Indigenous settlement.
visibilityA measure of the opacity of the atmosphere, and therefore, the greatest distance one can see prominent objects with normal eyesight
thalwegThe path connecting the deepest points along a stream channel.
nominal diameterEquivalent spherical diameter of a hypothetical sphere of the same volume as a given sediment particle.
infraredThe long wave, electromagnetic radiation of radiant heat emitted by all hot objects
dissolved gas concentrationsThe amount of chemicals normally occurring as gases, such as nitrogen and oxygen, that are held in solution in water, expressed in units such as milligrams of the gas per liter of liquid
maximumThe greatest value attained by a function, for example, temperature, pressure, or wind speed
effluentwaste liquid from a house, industry, sewage treatment plant, etc.
abyssal plainThe flat, gently sloping or nearly level region of the sea floor.
brackish waterGenerally, water containing dissolved minerals in amounts that exceed normally acceptable standards for municipal, domestic, and irrigation uses
median particle sizevalue for which half the particles in a sample have a greater diameter and half a lesser diameter.
instream coveroverhanging or instream structure, such as tree roots, undercut streambanks, boulders, or aquatic vegetation that offer protection for aquatic organisms.
meltwaterwater that comes from the melting ice of a glacier or a snowbank.
bank-full capacitythe rate of water flow that completely fills a channel; the flow rate at which the water surface is level with the flood plain.
aquaticrefers to water aquatic insect: insect species whose larval stages live in water
wildlifeany animal that is not tamed or domesticated
riprapRock or other material with a specific mixture of sizes referred to as a "gradation" used to stabilize streambanks or riverbanks from erosion or to create habitat features in a stream.
hygrometerAn instrument that measures the humidity of the air or other gases, especially the relative humidity.
rillA rill is a very small channel of water, caused mainly by runoff water that eroded the soil.
bed-formsTopography of the riverbed: the sediment formed structures on the bed.
pressure tendencyThe pressure characteristic and amount of pressure change during a specified time period, usually the three hour period preceding the observation.
seasonal application efficiencyThe sum of evapotranspiration of applied water and leaching requirement divided by the total applied water, expressed as a percentage: SAE=(ETAW+LR)/AW.
shear stressthe frictional force per unit area exerted on a streambed by flowing water
leveesAn artificial or natural bank or length of raised ground, constructed along a swamp or river to confine flood water to the main channel.
thalwegthe line of maximum depth in a stream
depositiondepositing of material by a stream, generally at points of reduced stream flow
litterfallLeaves, branches or other material having fallen from vegetation.
nonpoint sourcesource of pollution in which wastes are not released at one specific, identifiable point but from a number of points that are spread out and difficult to identify and control
conveyanceContinuous transport of water.
environmental flowsAny river flow pattern provided with the intention of maintaining or improving river health.
water recyclingthe treatment of wastewater making it suitable for reuse.
anaerobica life or process that occurs in, or is not destroyed by, the absence of oxygen.
diastereomeris a stereoisomer of a compound having two or more chiral centers that is not a mirror image of another stereoisomer of the same compound i.e borneol and isoborneol
well pluga seal installed in a borehole or well preventing movement of fluids.
divergenceWind movement that results in a horizontal net outflow of air from a particular region
transport capacityThe ability of a stream, for a given flow condition, to transport a volume (or weight) of sediment material of a specific size per unit time.
nowcastA short-term weather forecast for expected conditions in the next few hours.
radius of influencethe radial distance from the center of a wellbore to the point where there is no lowering of the water table or potentiometric surface; the edge of the cone of depression.
reachA length of channel uniform with respect to discharge, area and slope
tornadoA violently rotating column of air in contact with and extending between a convective cloud and the surface of the earth
flood guide levelThe elevation of a reservoir above which the space is reserved for temporary storage of water to help reduce downstream flooding.
unsaturated zonethe area above the water table where soil pores are not fully saturated, although some water may be present.
aggradationThe process by which streams and other water bodies are raised in elevation by the deposition of material eroded and transported from other areas
aquifera geologic formation that will yield water to a well in sufficient quantities to make the production of water from this formation feasible for beneficial use; permeable layers of underground rock or sand that hold or transmit groundwater below the water table.
ionan electrically charged atom or molecule
cross-connectionany actual or potential connection between a drinking water system and an unapproved water supply or other source of contamination.
non-aqueous phase liquidcontaminants that remain undiluted as the original bulk liquid in the subsurface, such as spilled oil.
groundwater tableThe upper surface of the zone of saturation, except where the surface is formed by an impermeable body.
percolating waterswaters passing through the ground beneath the Earth's surface without a definite channel.
correlative rightsrights that are coequal or that relate to one another, so that any one owner cannot take more than his share.
fog bankA fairly well-defined mass of fog observed in the distance
gray waterWaste water from a household or small commercial establishment which specifically excludes water from a toilet, kitchen sink, dishwasher, or water used for washing diapers.
erosionthe wearing away of a riverbank caused by continuous movement of water and wind.
confluenceWhere two rivers or streams meet.
macrophytesliterally ‘big plants
geneticsthe science of heredity and variation in living organisms
riffleShallow, steeper, section of stream with fast currents at low flow
isodrosothermThe line drawn on a weather map connecting points of equal dew point.
fish flows"Artificially increased flows in the river system called for in the fish and wildlife program to quickly move the young fish down the river during their spring migration period
saltationThe leaping movement of sand or soil particles as they are transported in a fluid medium over an uneven surface.
drainage areaThe total surface area that drains to a point of interest, typically reported in acres (small watersheds) or square miles.
watermasterAn employee of a water department who distributes available water supply at the request of water right holders and collects hydrographic data.
discharge permita permit issued by a state or the federal government to discharge effluent into waters of the state or the United States
ponda body of water usually smaller than a lake and larger than a pool either naturally or artificially confined.
volatilitythe tendency of a liquid to evaporate.
externallyon the outside of the sturgeon body
understoreyGround cover and below ground biomass (roots, bulbs and the seed bank).
subtropical airAn air mass that forms over the subtropical region
lockConsists of a rectangular chamber of concrete with gates at each end to regulate flow and permit boats to move from one water level to another.
hydraulic gradientthe direction of groundwater flow due to changes in the depth of the water table.
catalina eddyA weak low pressure circulation that may form off the Southern California coast.
floodsflows that are high enough at their peak to overrun river banks.
west virginia highAn area of stagnant high pressure located over West Virginia during Indian Summer.
aggressive waterwater which is soft and acidic and can corrode plumbing, piping, and appliances.
interbasin transferthe physical transfer of water from one watershed to another; regulated by the Texas Water Code.
watershedland area from which water drains toward a common watercourse in a natural basin.
quarternaryA geological name given to the period of time that covers the last 2 million years.
aggradationThe accumulation of stratigraphic sequences by deposition that stacks beds atop each other, building upwards during periods of balance between sediment supply and accommodation.
reservoirA reservoir is an artificial lake created by building a dam across a river.
leveeAn embankment constructed to prevent a river from overflowing (flooding).
stream channelA long narrow depression shaped by the concentrated flow of a stream and covered continuously or periodically by water.
siltA soil separate consisting of particles between 0.002 and 0.02 mm in equivalent diameter.
infraredA type of thermometry that measures the amount of infrared energy being emitted by a substance and compares that value to a predictable curve to calculate temperature.
total drop or heightThe total vertical distance, from the first crest to the last base, of a close series of waterfalls
primary treatmentmechanical treatment in which large solids are screened out and suspended solids in the sewage settle out as sludge
transpirationdirect transfer of water from the leaves of living plants to the atmosphere
cutoff wallWall, usually of sheet piling or concrete, that extends down to scour‑resistant material or below the expected scour depth.
fill slopeSide or end slope of an earth‑fill embankment
precipitationA general term for all forms of water particles ­ rain, snow, sleet, dew, hail etc.
channelBed and banks that confine surface flow of a stream.
teflonA registered trademark
salinityamount of dissolved salts in a given volume of water.
zenithThe point which is elevated 90 degrees from all points on a given observer's astronomical horizon
return periodSee Recurrence Interval.
oligotrophicLacking in plant nutrients and having a large amount of dissolved oxygen throughout.
riprapUsually refers to rocks or concrete structures used to stabilize stream or river banks from erosion.
stage-discharge relationship/curveA graph showing the relation between gage height (or stage) and the amount of water flowing in the channel.
dental fluorosisdisorder caused by excessive absorption of fluorine and characterized by brown staining of teeth.
barA shoal that develops at the mouth of a river as sediment carried by the river is deposited as the current slows or is impedded by wave action
rawinsondeAn upper air observation that evaluates the winds, temperature, relative humidity, and pressure aloft by means of a balloon-attached radiosonde that is tracked by a radar or radio direction-finder
nadirThe point on any given observer's celestial sphere diametrically opposite of one's zenith.
escarpmentA long, cliff-like ridge of land or rock
disinfectantkilling       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.
weatherday to day variation in atmospheric conditions
hyperchromicIncreased absorption of UV-Vis light (opposite: hypochromic)
bedrockSolid rock exposed at the surface of the earth or overlain by soils and unconsolidated material.
erosionWearing away of rock or soil by the gradual detachment of soil or rock fragments by water, wind, ice, and other mechanical, chemical, or biological forces.
irrigationdiversion of waterway to water agricultural crops
pebble countMethod for determination of the size distribution of channel bed materials.
collector wella well located near a surface water supply used to lower the water table and thereby induce infiltration of surface water through the bed of the water body to the well.
erosionThe process by which the land surface is detached and transported away by the action of water, wind, ice or gravity.
water cycleThe water cycle the natural cycle in which the sun's energy evaporates water into the atmosphere, and the water vapor condenses, returning to the Earth as precipitation (rain, snow, sleet, etc.).
hemispherehalf of a sphere; half of the earth
condensationThe process by which a vapour becomes a liquid or solid; the opposite of evaporation
phenolsorganic compounds that are byproducts of petroleum refining; tanning; and textile, dye, and resin manufacturing
navier-stokes equationsa set of equations that describe the physics governing the motion of a fluid
spoilDirt or rock that has been removed from its original location.
pyrolysisis the process where organic compounds decompose when heated without burning.
bankthe sloping land bordering a stream channel that forms the usual boundaries of a channel
semi-confined aquiferan aquifer partially confined by soil layers of low permeability in which recharge and discharge can still occur.
zaitsev rulepredicts the formation of an alkene based on thermodynamic stability: the alkene with the highest the degree of substitution is preferentially formed under thermodynamic conditions.
chromophoreis a chemical group that absorbs light at a specific wavelength and so imparts color to a molecule i.e
zodiacThe position of the sun during the course of the year as it appears to move though successive constellations
mesoscale convective complexA large mesoscale convective system (MCS) which is about the size of the state of Ohio or Iowa and lasts at least 6 hours
leachatewater containing contaminants which leaks from a disposal site such as a landfill or dump.
frontal passageIt is the passage of a front over a specific point on the surface
peatPartially decomposed plants and other organic material that build up in poorly drained wetland habitats.
national response teamrepresentatives of 13 federal agencies that, as a team, coordinate federal responses to nationally significant incidents of pollution and provide advice and technical assistance to the responding agencies.
precautionary principleIf there are threats of serious or irreversible environmental damage, lack of full scientific certainty should not be used as a reason for postponing measures to prevent environmental degradation.
backsiphonagereverse seepage of water in a distribution system.
fluvialFrom the Latin word fluvius, meaning river.
cutoff(A) Direct channel, either natural or artificial, connecting two points on a stream, thereby shortening the original length of the channel and increasing its slope; (B) natural or artificial channel which develops across the neck of a meander loop (neck cutoff) or across a point bar (chute cutoff).
active floodplainThe level area adjacent to a stream channel that is subject to frequent overflow.
data buoysBuoys placed throughout the Gulf of Mexico and along the Atlantic and Pacific coasts of the United States that relay information on air and water temperature, wind speed, air pressure, and wave conditions via radio signals.
oceanThe intercommunicating body of salt water occupying the depressions of the earth's surface, or one of its major primary subdivisions, bounded by the continents, or the equator, and other imaginary lines
distilled waterwater that has been treated by boiling and condensation to remove solids, inorganics, and some organic chemicals.
water qualityA term used to describe the physical, chemical and biological characteristics of water with respect to its suitability for a particular use.
effectivenessThe extent to which project outcomes (see 'outcomes') are achieving project objectives.
rossby wavesThe movement of ridges and troughs in the upper wind patterns, primarily the jet stream, circling the earth
pollutantor the pollutant or substance       itself, such that the final concentration after mixing is lower than that in the effluent or of the       pure substance.
cohesiona molecular attraction by which the particles of a body are united throughout the mass whether like or unlike
hypsochromic shiftis the shift to lower wavelength in the UV-Vis spectrum (opposite: bathochromic)
biotaAll living organisms of a region, as in a stream or other body of water.
bulk densityDensity of the water sediment mixture (mass per unit volume), including both water and sediment.
flow metera gauge indicating the velocity and/or volume of a flowing liquid.
hydraulic gradientThe slope or the water surface
main stemThe principal channel of a drainage system into which other smaller streams or rivers flow.
geomorphologyOf, or relating to, the forms of the earth's surface and the processes associated with them (e.g
meander amplitudeDistance between points of maximum curvature of successive meanders of opposite phase in a direction normal to the general course of the meander belt, measured between center lines of channels.
ml/dMegalitres per day.
densitya measure of how heavy a specific volume of a solid, liquid, or gas is in comparison to water.
growing seasonConsidered the period of the year during which the temperature of cultivated vegetation remains sufficiently high enough to allow plant growth
water yeara division based on a general pattern of annual wet and dry periods rather than a calendar year
silttiny, fine particles suspended in or deposited by water
conservationto protect from loss and waste
beaufort wind scaleA system of estimating and reporting wind speeds
geyserA geyser is a natural hot spring that occasionally sprays water and steam above the ground.
sheet erosionThe removal by surface runoff of a fairly uniform layer of soil from a bank slope from "sheet flow" or runoff that flows over the ground surface as a thin, even layer not concentrated in a channel.
skew t-log p diagramA thermodynamic diagram, using the temperature and the logarithm of pressure as coordinates
ambient mediummaterial surrounding or contacting an organism (e.g., outdoor air, indoor air, water, or soil through which chemicals or pollutants can reach the organism.
air mass thunderstormA thunderstorm that is produced by convection within an unstable air mass through an instability mechanism
drainage networkThe system of channels and pipes and overland flow pathways which drain a catchment area (ARMCANZ & ANZECC 2000).
easterly waveAn inverted, migratory wave-like disturbance or trough in the tropical region that moves from east to west, generally creating only a shift in winds and rain
minimumThe least value attained by a function, for example, temperature, pressure, or wind speed
augmentationIncreasing steam flow under normal conditions, by releasing storage water from reservoirs.
channelAn area containing continuously or periodically flowing water that is confined by banks and a streambed.
pressure changeThe net difference between the barometric pressure at the beginning and ending of a specified interval of time, usually the three hour period preceding an observation.
anaerobic or anoxic zoneAn environment devoid of oxygen (ARMCANZ & ANZECC 2000).
ecosystemAn ecological community together with its environment, functioning as a unit.
hydroelectricityElectric energy produced by water-powered turbine generators.
thunder snowA wintertime thunderstorm from which falls snow instead of rain
off-takesFlow of water that is separated from a main body by a channel or diversion structure.
tropospherethe layer of atmosphere closest to the Earth, extending seven to ten miles above the surface, containing most of the clouds and moisture.
watershedAn area of land whose total surface drainage flows to a single point in a stream.
cataractThe descent of a very large volume of water over any combination of rapids, cascades, and falls, often through a narrow gorge.
conductionThe transfer of heat through a substance by molecular action or from one substance by being in contact with another.
drainage basinThe total area of land from which water drains into a specific river.
water conservationReduction in applied water due to more efficient water use such as implementation of Urban Best Management Practices or Agricultural Efficient Water Management Practices
poolA reach of stream that is characterized by deep low velocity water and a smooth surface.
vortexAny circular or rotary flow in the atmosphere that possesses vorticity.
reforestationThe natural or artificial restocking of an area with forested trees.
hydrologic balancean accounting of all water inflow into, outflow from and changes in water storage within a hydrologic unit over a specified period of time
damsearth or other construction along a river to control water flow
stream orderA method for classifying streams as part of a drainage network
abrasionRemoval of streambank material due to entrained sediment, ice, or debris rubbing against the bank.
populationgroup of individuals of a specific kind, in a given area, at a given time
benthosAll plants and animals living on or closely associated with the bottom of a body of water.
municipal sludgesemi-liquid residue remaining from the treatment of municipal water and wastewater.
glaciera body of snow and ice that moves like a river
tiltThe inclination to the vertical of a significant feature of the pressure pattern or of the field of moisture or temperature
grassed waterwaynatural or constructed watercourse or outlet that is shaped or graded and planted in suitable vegetation for the disposal of runoff water without erosion.
populationThe total number of a single species (i.e., group of interbreeding organisms) inhabiting a particular locality.
flowing artesian wella special case of an artesian well where a water well drilled into a confined aquifer has enough hydraulic pressure for the water to rise to a height above ground surface and to flow at the surface without pumping.
macroburstA large downburst with an outflow diameter of 2.5 miles (4 kilometers) or larger and damaging winds.
phThe negative logarithm of the molar concentration of the hydrogen ion, or, more simply acidity.
first step decisionA decision announced in November 2003 by the Murray-Darling Basin Ministerial Council.
riffleA reach of stream that is characterized by shallow, fast moving water broken by the presence of rocks and boulders.
time constantAs defined by engineering sciences, a time constant is the actual time that a physical system requires to reach 62.3% of its total value
driftAlternate term for vegetative "debris."
food-webA conceptual way of showing how plants and animals in a habitat depend on each other.
lotticMoving water.
conservation areaDesignated land where conservation strategies are applied for the purpose of attaining a viable plant or animal population.
leveeEmbankment, generally landward of top bank, that confines flow during high-water periods, thus preventing overflow into lowlands.
embeddednessThe degree to which the coarse channel bed materials (boulders, cobble, gravel, sand) are surrounded or covered by fine sediments, usually measured as percent coverage by finer sediments.
pipingThe process by which water forces an opening around or through a supposedly sealed structure, such as a check dam or levee
benthic macroinvertebrateBackboneless aquatic animals that dwell on or in the bottom sediments of a stream channel that are large enough to be seem by the unaided eye.
bioaccumulationProcess in which the level of toxic substances in an organism increase over time due to continued exposure.
total dissolved solidsA quantitative measure of the residual minerals dissolved in water that remain after evaporation of a solution
pollutantParticles, gases, or liquid aerosols in the atmosphere which have an undesirable effect on humans or their surroundings
flood storageThe volume, or capacity, in a reservoir that is reserved for the storage of floodwater.
water regimeRefers to flow pattern and timing of flows.
unclassified watersthose waters for which no classification has been assigned and which have not been identified in Appendix A of 31 Texas Administrative Code, Chapter 307.10 of Title 31 (relating to definitions).
outfallthe place where a wastewater treatment plant discharges treated water into the environment.
spot sizeThe diameter of the circle formed by the intersection of the field of view of an infrared thermometer with the surface being measured
tidal flatsSaltwater wetlands that are characterized by mud or sand and daily tidal fluctuations.
clearTo restore a device to a its initial state, usually the zero state.
heat exhaustionThe effect of excessive heat, particularly when combined with high humidity, on a human being
greywaterwastewater from clothes washing machines, showers, bathtubs, handwashing, lavatories and sinks that are not used for disposal of chemical or chemical-biological ingredients.
habitat indicatora physical attribute of the environment measured to characterize conditions necessary to support an organism, population, or community in the absence of pollutants
ecological modellingA representation of an ecological system, either qualitative or quantitative, that can predict, simulate or identify a response as a result of perturbation from an environmental process outside of the ecological system identified.
energy dissipationThe loss of kinetic energy of moving water due to internal turbulence, bottom friction, large rocks, debris, or other obstacles that impede flow.
isothermline that connects points of equal temperature.
guilda group of species or organisms that use the same environmental resources (habitat, food source, etc.) or life history strategy (such as reproduction) in the same way.
producersplants that manufacture food from inorganic nutrients
outcropexposed at the surface
national priorities listEPA's list of the most serious uncontrolled or abandoned hazardous waste sites identified for possible long-term remedial action under Superfund
headcutA break in the slope at the top of a gully or section of a gully that forms a "waterfall" which in turn causes the underlying soil to erode and the gully to expand uphill.
recurrence intervalThe interval of time, on average, between occurrences of a hydrologic event of a certain magnitude.
gravelSee cobble.
bioclasticSediment or rock formations developed as a result of expulsion from a volcano.
dissolved oxygenamount of oxygen gas dissolved in a given quantity of water at a given temperature and atmospheric pressure
performance monitoringGathering of information to measure the success of strategies implemented when compared to objectives (see 'objectives').
abrasionRemoval of stream-bank soil as a result of sediment-laden water, ice, or debris rubbing against the bank.
earthquakeA sudden, transient motion or trembling of the earth's crust, resulting from the waves in the earth caused by faulting of the rocks or by volcanic activity.
wave cycloneA cyclone which forms and moves along a front
temperature stratificationThe variation of water temperature at different depths in a reservoir
woody debrisAny large, relatively stable woody material that intrudes into the stream channel.
flow-control structureStructure either within or outside a channel that acts as a countermeasure by controlling the direction, depth, or velocity of flowing water.
lock-and-key methoddescribes the selectivity of enzymes towards certain substrates over others
state revolving fundsa program, capitalized in part by federal funds, that provides low-interest loans for construction of publicly owned wastewater treatment and water recycling facilities, for implementation of nonpoint source and storm drainage pollution control management programs, and for the development and implementation of estuary conservation and management programs.
fillingUsed in describing the history of a low pressure system or an area of cyclonic circulation, it means an increase in the central pressure of the system
erosionthe movement of rock and soil
runoffWater that flows over the surface of a catchment area.
polar air massAn air mass that forms over a high latitude region
blackbodyA theoretical material that absorbs all incident electromagnetic radiation and reflects none
social/cultural valuesSocial values include public health and safety, recreational uses and visual amenity
filter fabricA polypropylene textile used to keep soil separate from water
environmental monitoringThe process of checking, observing, or keeping track of something for a specified period of time or at specified intervals.
magnetic polesEither of the two points on the earth's surface where the magnetic meridians converge
effluent(1) Something that flows out or forth, especially a stream flowing out of a body of water
kilolitreone thousand litres
dischargeThe volume of water passing through a channel during a given time, usually measured in cubic feet per second.
rechargerefers to water entering an underground aquifer through faults, fractures, or direct absorption.
demandthe number of units of something that will be purchased at various prices at a point in time
molluscsFresh and marine organisms which usually have a shell
stream ordera system used to classify (and analyze) streams
mg/lMilligrams per litre.
in-siturefers to the synthesis of a reactive intermediate, which is not isolated since it is too difficult or too dangerou
recapturedto find and capture the same fish consecutive times
habitatthe type of environment in which a given animal or plant lives and grows, including physical and biological conditions.
map scaleThe relationship between the actual size of a place and its size as shown on a map.
crystallizationThe process of a substance going directly from a vapor form (water vapor) to a solid (ice) at the same temperature, without going through the liquid phase (water)
wettabilitythe degree to which a fluid will spread into or coat a solid surface in the presence of other fluids into which it will not dissolve.
soil erodibilityAn indicator of a soil's susceptibility to raindrop impact, runoff, and other eroding processes.
meander belt widthThe distance between lines drawn tangential to the extreme limits of fully developed meanders
triple-bottom-line assessmentA process which uses multi-criteria analysis to evaluate the economic, social and ecological costs and benefits of possible Best Management Practices.
effluentThe sewage or industrial liquid waste that is released into natural water by sewage treatment plants, industry, or septic tanks.
ceiling lightAn instrument consisting of a drum and an optical system that projects a narrow vertical beam of light onto a cloud base.
radius of curvatureThe radius of the circular arc that best describes the outside bend of a stream meander.
field capacitythe amount of water held in soil against the pull of gravity.
suspended sedimentsparticles carried in water without being dissolved
ecological indicatorAn attribute of an ecosystem whose presence or absence, quantity, level, pattern, or etc
turbidityA measure of the content of suspended matter that interferes with the passage of light through the water or in which visual depth is restricted
ecospheretotal of all the ecosystems on the planet, along with their interactions; the sphere of air, water, and land in which all life is found.
toxaphenechemical that causes adverse health effects in domestic water supplies and is toxic to fresh water and marine aquatic life.
environmental assessmentThe critical appraisal of the likely effects of a proposed project, activity, or policy on the environment, both positive and negative.
colorado lowA low pressure disturbance that forms in the lee of the Rocky Mountains, usually in southeastern Colorado.
technology-based treatment requirementsNPDES permit requirements based on the application of pollution treatment or control technologies including BTP (best practicable technology), BCT (best conventional technology), BAT (best available technology economically achievable), and NSPS (new source performance standards).
pollutant(1) Something that pollutes, especially a waste material that contaminates air, soil, or water
acreA measure of area equal to 43,560 ft2 (4,046.87 m2)
riparianLocated on the banks or a stream or other body of water.
moisture holding capacitythe amount of liquid that can be held against gravity, by waste materials or soil, without generating free liquid.
contaminantorganism, 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.
hydraulicsThe physical forces that interact between the river and it's surrounding landscape.
angle of reposeMaximum angle (as measured from the horizontal) at which gravel or sand particles can stand.
efficiencyThe extent to which project outputs (see 'outputs') are maximised for the given level of inputs
point barsThe convex side of a meander bend that is built up due to sediment deposition.
fine sediment loadThat part of the total sediment load that is composed of particle sizes finer than those represented in the bed (wash load)
soft waterany water that does not contain a significant amount of dissolved minerals such as salts of calcium or magnesium.
canyonA canyon is a deep valley with very steep sides - often carved from the Earth by a river.
limnologyscientific study of physical, chemical, and biological conditions in lakes, ponds, and streams.
storage reservoirA reservoir that can be used to store water for a variety of purposes, such as flood damage reduction, power production, navigation, water supply, and recreation.
reservoira pond, lake, tank, or basin (natural or human made) where water is collected and used for storage
hygrographAn instrument that records the hygrometer's measure of water vapor.
decantthe process in the laboratory when a liquid is transferred into a different container and the solid is left behind
wasteload allocationterm used in conjunction with the TMDL Program, a WLA is the portion of a receiving water's loading capacity that is allocated to one of its existing or future point sources of pollution
fresheta sharp rise in discharge or a flood event associated with rainfall or snow melt
cobbleFragment of rock whose diameter is in the range of 64 to 250 mm.
catchmentA topographically defined area draining surface water to a single outlet point.
glideShallow, low gradient stream sections with slow current and fine substrate.
sun pillarHorizontal ice crystals in the form of plates, which occur in clouds and ice fog near the earth's surface, reflect sunlight into vertical sun pillars for a spectacular display.
resolutionIn relation to radar, it is the ability to read two distinct targets separately
cross-sectional areaThe area of cross-section below the water surface perpendicular to the direction of flow.
phA measure of the hydrogen ion concentration of water or wastewater; expressed as the negative log of the hydrogen ion concentration [H+]
streambank erosionThe wearing away of streambanks by flowing water.
phragmitesA common reed found on the edges of creeks and rivers, especially near coast.
cold lowA low pressure system that has its coldest temperatures at or near the center of circulation, and is thermally barotropic with respect to a horizontal plane
salineSalty water - water from the sea is known as saltwater, or saline
rifflesSections of flowing water in a stream
dissolved solidsinorganic material contained in water or wastes
mass wastingLarge slope failures associated with downcutting stream channels and undermined support of steep slopes
opportunistic macroalgaeLarge algae (eg Ulva, Hincksia, etc) that grow rapidly in marine waters when nutrients are high.
microscaleThe smallest scale of meteorological phenomena that range in size from a few centimeters to a few kilometers
floodplainthe area on either side of the bankfull channel that carries the flow greater than the bankfull flow, that is, all storms greater than the one-to-two year storm
blowdownTrees felled at the base by high winds.
unrestricted drawdownThe lowering of reservoir levels with no restrictions on the rate of change.
thermal pollutionan increase in air or water temperature that disturbs the climate or ecology of an area.
catchmentSee drainage basin.
fetch lengthHorizontal distance (in the direction of the wind) over which wind generates waves and wind setup.
condensation funnelA funnel-shaped cloud consisting of condensed water drops that has possible rotation.
swellOcean waves that have traveled out of their generating area
k indexThe measure of thunderstorm potential based on the vertical temperature lapse rate, the moisture content of the lower atmosphere and the vertical extent of the moist layer.
basinSee Drainage Basin.
critical shear stressThe minimum amount of shear stress required to initiate substrate particle motion along the stream bed or banks.
fahrenheit temperature scaleA temperature scale where water at sea level has a freezing point of +32°F and a boiling point of +212°F
runoffsurface water entering rivers, freshwater lakes, or reservoirs.
national response centerThe 24-hour a day federal operations center receives notifications of all releases of oil and hazardous substances into the environment
barragesAn artificial bar or obstruction placed in a river or water course to increase the depth of water or obstruct flow.
zooplanktonSmall, free-floating or weakly swimming animals that are difficult to see with the naked eye.
loadWhat the river carries along with it - mud, sand, rocks, wood
well injectionthe subsurface placement of fluids into a well.
artesian aquifera geologic formation in which water is under sufficient hydrostatic pressure to rise above the top of the aquifer in the subsurface
blowdownthe water drawn from boiler systems and cold water basins of cooling towers to prevent the buildup of solids.
bodBiochemical Oxygen Demand
chenopodFrom New Latin Chenopodiceae, meaning a small shrub or bush tolerant of dry and salty conditions, commonly found as an understorey species.
stratificationwhen the water in a dam or weir pool forms layers that do not readily mix with each other.
ambient bed elevationInitial (unscoured) bed elevation.
eyeThe center of a tropical storm or hurricane, characterized by a roughly circular area of light winds and rain-free skies
plunge poolA deeply eroded depression in the stream bed, found at the base of some waterfalls.
rangeThe values that a particular instrument is intended to measure, usually noted in a specification table by upper and lower limits.
streambank protection worksStructure placed on or near a distressed stream bank to control bank erosion or prevent failure.
splash-proofA non-technical term used to describe instruments that are protected from ingress caused by the splashing of liquids but not necessarily protected against immersion
dredgingThe removal of material from the bottom of water bodies using a scooping machine
nephelometricmethod of measuring turbidity in a water sample by passing light through the sample and measuring the amount of light deflected.
flowin 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.
chromosphereA thin layer of relatively transparent gases above the photosphere of the sun
interstitial flowWater flow through bed (i.e., riffle) and bar materials.
distillationis a technique to purify liquids based on different boiling points
backwaterCondition in which the water surface elevation is raised by downstream flow impediments.
scour poolAn area of deeper water created by the scouring action of water
bulkheadVertical, or near vertical, wall that supports a bank or an embankment; also may serve to protect against erosion.
effective dischargeThe discharge that transports the largest fraction of the annual sediment load
hydrostatic pressurepressure exerted by or existing within a liquid at rest with respect to adjacent bodies.
superfund listA list of the hazardous waste disposal sites most in need of cleanup
ephemeral streamsones that flow only during and shortly after extreme rainfall or snowmelt
streambank erosionThe removal of soil from streambanks by flowing water.
water tablelevel below the earth's surface at which the ground becomes saturated with water
evapotranspirationwater lost from plants through evaporation and photosynthesis
megawatt-hourAn amount of energy that equals one million watt-hours
retrofittinginstalling modern pollution control devices at facilities without making major changes to the facility's design.
gravityThe force of attraction of the earth on an object
locationA place where something can be found.
organic compounda ring molecule of six carbons and six hydrogens with three shared or       resonant double carbon-to-carbon bonds, known as an aromatic compound.
lockSee hold.
frontogenesisThe birth or creation of a front
freezing fogUsed to describe the phenomena when fog is present and the air temperature is below 0°C
blindswater samples containing a chemical of known concentration given a fictitious company name and slipped into the sample flow of the lab to test the impartiality of the lab staff.
dissolvethe process by which solid particles mix molecule by molecule with a liquid and appear to become part of the liquid.
depth of scourVertical distance a streambed is lowered by scour below a reference elevation.
ecosystem restorationRestoration of all or part of the functions and structures of a previously degraded ecosystem.
celestial sphereThe apparent sphere of infinite radius having the earth as its center
boulderA large substrate particle that is larger than cobble, 256 mm in diameter.
assaya test for a specific chemical, microbe, or effect.
lenticOf standing (or still) water.
nutrientssubstances, such as phosphorus and nitrogen, that are necessary for plants (including algae) to grow.
seepa spot where water contained in the ground oozes slowly to the surface and often forms a pool; a small spring.
pressure characteristicThe pattern of the pressure change during the specified period of time, usually the three hour period preceding an observation
ground waterwater that sinks into the soil and collects over impermeable rode; it then flows laterally toward a stream, lake or ocean.
armoringthe formation of an erosion-resistant layer of relatively large particles on a streambed or bank resulting from removal of finer particles by erosion.
deep percolationthe percolation of water through the ground and beyond the lower limit of the root zone of plants into a groundwater aquifer.
riverA river is a naturally winding watercourse that drains surplus water from a drainage basin.
diatomaceousconsisting of or abounding in diatoms, a class of unicellular or colonial algae having a silicified cell wall that persists as a skeleton after death.
sillsRefers to the upper level of a levee, dam or regulator, above which flow spills into or out of the structure.
pilot balloonA small balloon whose ascent is used to determine the direction and speed of low level atmospheric winds
currentThe flow of the river.
median streamflowthe rate of discharge of a stream for which there are equal numbers of greater and lesser flow occurrences during a specified period.
riparian areasAn area of land directly influenced by water
aphelionThe point on the earth's orbit that is farthest from the sun
barbelsa whisker-like sensor that protrudes from the mouth area of a sturgeon and is used to sense food in murky water
treatmentany method, technique, or process designed to remove solids and/or pollutants from solid waste, waste-streams, and effluents.
geopressured reservoira geothermal reservoir consisting of porous sands containing water or brine at high temperature or pressure.
watershedthe geographic area that drains into a particular river.
subsistence flowsthe component of an instream flow regime that represents infrequent, naturally occurring low flow events that occur for a seasonal period of time
channelAn area that contains continuously or periodically flowing water that is confined by banks and a streambed.
mermaida fabled marine creature usually represented as having the head, trunk, and arms of a woman and a lower part like the tail of a fish.
water qualityA term used to describe the chemical, physical, and biological characteristics of water, usually in respect to its suitability for a particular purpose.
monitoring wella well used to obtain water quality samples or measure groundwater levels.
culvertA buried pipe that allows flows to pass under a road.
management responsesAquatic ecosystem condition reports include management responses that are being coordinated by community, industry and government sectors
rapidsAny descent of a stream over a moderately steep slope in its stream bed
nsf certifiedThis icon indicates that the design, materials, production process and quality controls used in the production of a product have been verified and certified for food safety by a highly respected third party non-profit organization, the National Sanitation Foundation (NSF).
finite volumea method of solving the governing equations of a numerical model by dividing the spatial domain into a mesh of nodes and corresponding volumes around each node
mean temperatureThe average of temperature readings taken over a specified amount of time
gabionA wire basket or cage that is filled with gravel or cobble and generally used to stabilize streambanks.
gigalitreone thousand million litres
cobblerock from 7 to 30 an (3 to 12 inches) in diameter; rubble
electromagnetic radiationAlso called radiation, it is waves of energy propagated though space or through a material media.
pooldeeper and slower flowing water in a stream or river
meander radius of curvatureRadius of a circle inscribed on the centerline of a meander loop.
climatic cyclethe periodic changes climate displays, such as a series of dry years following a series of years with heavy rainfall.
cumulus fractusCumulus clouds that appear in irregular fragments, as if they had been shred or torn
flashinessWhere water levels rapidly peak and decline.
adaptive managementA type of management where the approach to managing resources evolves over time as new ideas, information, drivers for change and technologies emerge.
bifurcationA fork into two or more streams.
equatorThe geographic circle at 0 degrees latitude on the earth's surface
backpressurea pressure that can cause water to backflow into the water supply when a user's wastewater system is at a higher pressure than the public system.
tsunamiAn ocean wave with a long period that is formed by an underwater earthquake or landslide, or volcanic eruption
seweragethe entire system of sewage collection, treatment, and disposal.
rechargeWater that infiltrates through the soil surface to the watertable.
leachate collection systema system that gathers leachate and pumps it to the surface for treatment.
stream channelThe bed where a natural stream of water runs or may run; the long narrow depression shaped by the concentrated flow of a stream and covered continuously or periodically by water.
aridA term describing a climate or region in which precipitation is so deficient in quantity or occurs so infrequently that intensive agricultural production is not possible without irrigation.
flood attenuationTo lessen the amount, force or severity of high flows.
reservoirbay or       other system, based upon flow rates into and out of the system, (see residence time).
surplus waterDeveloped water supplies in excess of contract entitlement or apportioned water.
zonal indexThe measure of the strength of the westerly winds of the middle latitudes
barometerAn instrument used to measure atmospheric pressure
peclet numberthe relationship between properties of the mesh, fluid velocity, and eddy viscosity for a hydraulic computer model.
storm windsOn the Beaufort Wind Scale, a wind with speeds from 56 to 63 knots (64 to 72 miles per hour).
longitudinal profileProfile of a stream or channel drawn along the length of its centerline
helicityA property of a moving fluid, such as air, representing the potential for helical flow (flow that follows a corkscrew pattern)
mesoscale convective systemA large organized convective weather system comprised of a number of individual thunderstorms
vegetative controlsnon-point source pollution control practices that utilize vegetative cover to reduce erosion and minimize loss of pollutants.
cartilageconnective tissues without blood vessels
poolA reach of a stream that is characterized by deep, low-velocity water and a smooth surface.
organic chemicalschemicals containing carbon.
plunge poolA pool at the foot of a small water-fall in a river
groundwater storagethe storage of water in groundwater reservoirs.
decompositionbreakdown of organic materials
ablationThe process by which ice and snow waste away as a result of melting and/or evaporation.
megalitreone million litres (an Olympic swimming pool is about 2 megalitres).
pectoral finslocated directly behind the gill covers (operculum) on both sides of the sturgeon
enhancementEmphasis on improving the value of particular aspects of water and related land resources.
siltationthe deposition of finely divided soil and rock particles upon the bottom of stream and river beds and reservoirs.
hydrographA curve showing stream discharge over time.
bedrockconsolidated rock beneath the surface of the earth
peak dischargeMaximum flow.
mesaA mesa is a land formation with a flat area on top and steep walls - usually occurring in dry areas.
restricted drawdownA lowering of reservoir pool levels that is limited by one or more restrictions on the rate of change.
breakpoint chlorinationaddition of chlorine to the point where all organic matter and ammonia compounds have been destroyed and any additional chlorine becomes a free chlorine residual available for disinfection.
racemica mixture that is composed of equal amounts of dextrorotatory and levorotatory forms of the same compound and is not optically active
flood stageAn above average elevation for the water level at high flows.
herbaceousplants with soft rather than woody stems
outcomesThe results of the activities or products of a project
isohyetThe line drawn through geographic points recording equal amounts of rainfall during a given time or for a given of storm.
ppmparts per million or milligrams per litre (mg/l)
habitatThose parts of the environment on which particular plants or animals depend, directly or indirectly in order to carry out their life processes (modified from Newbury and Gaboury, 1993)
off-site enhancementThe improvement in conditions for fish or wildlife species away from the site of a hydroelectric project that had detrimental effects on fish and/or wildlife, as part or total compensation for those effects
phnumeric value that describes the intensity of the acid or basic (alkaline) conditions of a solution
purgeable organicsvolatile organic chemicals which can be forced out of the water sample with relative ease through purging.
tidal prismThe volume of water stored in an estuary or tidal lake between the high and low tide levels; the volume of water that moves into and out of the estuary over a tidal cycle.
velocityIn this concept, the speed of water flowing in a watercourse, such as a river.
diffluenceA rate at which wind flow spreads apart along an axis oriented normal to the flow in question
saturationthe condition of a liquid when it has taken into solution the maximum possible quantity of a given substance at a given temperature and pressure.
catchment(1) the catching or collecting of water, especially rainfall
valley breezeAn anabatic wind, it is formed during the day by the heating of the valley floor
bow echoA radar echo signature often associated with severe thunderstorms, especially those that produce wind damage
ephemeralTemporary or intermittent; a creek or wetland that dries up intermittently.
flood plainLevel land that may be submerged by flood waters.
hydric soilsSoils that are ponded, flooded, or saturated long enough during the growing season to develop anaerobic conditions.
absolute zeroThe coldest possible temperature, zero on the Kelvin scale, or approximately âˆ'273.15 °C, âˆ'459.67 °F
quantitative precipitation forecastA forecast of rainfall, snowfall or liquid equivalent of snowfall.
advectionThe horizontal transfer of any property in the atmosphere by the movement of air (wind)
heterogenic aquiferan aquifer that has a variety of forms or characteristics, such as differering permeabilities
spursprojection from the scutes of young sturgeon to deter predators
benthosAll the plant and animals living on or closely associated with the bottom of a body of water.
mainstem passageThe movement of salmon and steelhead around or through the dams and reservoirs in the Columbia and Snake rivers.
cold highA high pressure system that has its coldest temperatures at or near the center of circulation, and horizontally, is thermally barotropic
large woody debrisPieces of naturally occurring wood larger than 10 ft long and 6 in
precipitationwater that falls from the clouds - rain, snow, hail or sleet
parcelA volume of air small enough to contain uniform distribution of its meteorological properties and large enough to remain relatively self-contained and respond to all meteorological processes.
zooplanktonFloating microscopic animals.
santa ana windsThe hot, dry winds, generally from the east, that funnel through the Santa Ana river valley south of the San Gabriel and San Bernadino Mountains in southern California, including the Los Angeles basin
bank stabilisationSee 'stabilisation'.
floraplant population of a region.
weira wall or plate placed in an open channel to measure the flow of water; a wall or obstruction used to control flow from settling tanks and clarifiers to ensure a uniform flow rate and avoid short-circuiting.
gravelRock fragment whose diameter ranges from 2 to 64 mm.
moisture stressA condition of physiological stress in a plant caused by lack of water.
riffleA segment where the flow is shallower and more turbulent.
ecosystemA term that describes all the organisms living in a particular area, as well as all the non-living, physical components of the environment with which the organisms interact, such as air, soil and water.
methoxychlorpesticide that causes adverse health effects when found in domestic water supplies
resistanceThe ease or difficulty of changing an ecosystem; how "resistant" it is to being changed
sloughA shallow backwater inlet that is commonly exposed at low flow or tide.
aquaductA pipe or conduit made to bring water from a source.
trade windsTwo belts of prevailing winds that blow easterly from the subtropical high pressure centers towards the equatorial trough
synoptic chartAny map or chart that depicts meteorological or atmospheric conditions over a large area at any given time.
heatA form of energy transferred between two systems by virtue of a difference in temperature
feeder bandsIn tropical parlance, the lines or bands of thunderstorms that spiral into and around the center of a tropical system
riparian zoneThe band of vegetation located adjacent to a stream
channel migrationLateral or longitudinal (down-valley) migration of the stream channel within the valley by the process of erosion and deposition.
fryyoung fish which have absorbed their yolk sac, during the larvae stage, and begin hunting for food
hydraulicsApplied science concerned with behavior and flow of liquids, especially in pipes, channels, structures, and the ground.
streamflowThe rate at which water passes a given point in a stream or river, usually expressed in cubic feet per second (cfs).
diadromousRefers to fish that migrate between salt and fresh water.
chemical weatheringattack and dissolving of parent rock by exposure to rainwater, surface water, oxygen, and other gases in the atmosphere, and compounds secreted by organisms
geysera periodic thermal spring that results from the expansive force of super heated steam.
deltaA fan-shaped area of sediment built up at the mouth of a river.
volcanoA volcano is a mountainous vent in the Earth's crust
failureCollapse or slippage of a large mass of bank material into a stream.
kame terracea terrace of stratified sand and and gravel deposited by streams between a glacier and an adjacent valley wall.
indicatorsThe specific characteristics or phenomena that tell you about the project and what impact it is having on the problem or issue it was set up to address.
electrodialysisa process which uses an electrical current and an arrangement of permeable membranes to separate soluble minerals from water
habitatA part of the environment that has well-defined physical characteristics and is inhabited by a particular species or group of animals or plants.
nutrientssuch 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.
rain shadowAlso referred to as a precipitation shadow, it is the region on the lee side of a mountain or similar barrier where the precipitation is less than on the windward side
ramsar conventionsee Convention on Wetlands.
jambaThe Japan Australia Migratory Bird Agreement, a treaty between Australia and Japan to preserve habitat for migratory birds that are known to migrate between the two nations.
rootwadThe mass of roots associated with a tree adjacent or in a stream that provides refuge and nutrients for fish and other aquatic life.
reuseThe additional use of previously used water.
hazardous wasteWaste that poses a risk to human health or the environment and requires special disposal techniques to make it harmless or less dangerous.
remnant vegetationNative vegetation that remains after surrounding land has been cleared.
rocketsondeA type of radiosonde that is shot into the atmosphere by a rocket, allowing it to collect data during its parachute descent from a higher position in the atmosphere than a balloon could reach.
petroleum ether(also called Petrolether or ligroin) is a mixture of different hydrocarbons
endocrine functionThe endocrine system in an animal regulates hormone activity
cut offA channel cut across the neck of a bend.
yolk saca small sac attached to the larvae that provides nutrients needed to survive and grow
landscapeA heterogenous land area with interacting ecosystems that are repeated in similar form throughout.
cbodCarbonaceous Biochemical Oxygen Demand.  A BOD test in which a nitrification inhibitor is added, so that only the carbonaceous oxygen demanding compounds are measured. 
troposphereThe lowest layer of the atmosphere located between the earth's surface to approximately 11 miles (17 kilometers) into the atmosphere
revetmentA facing of stone, bags, blocks, pavement, etc., used to protect a bank against erosion.
flashinessTerm that describes the degree to which a watershed is able to attenuate the intensity of stormflows through infiltration, retention, detention, … A "flashy" watershed has a high degree of impervious surface resulting in fast, intense flood peaks.
imhoff conea clear, cone-shaped container used to measure the volume of settleable solids in a specific volume of water.
percolationThe movement of water downward through the subsurface to the zone of saturation.
bioassaya test to determine the relative strength of a substance by comparing its effect on a test organism with that of a standard preparation.
latitudeLatitude is the angular distance north or south from the equator to a particular location
bed layerFlow layer, several grain diameters thick (usually two) immediately above the bed.
damA barrier built, usually across a watercourse, for holding back water or diverting the flow of water.
centrifugal forceThe apparent force in a rotating system that deflects masses radially outward from the axis of rotation
contaminantAny physical, chemical, biological, or radiological substance or matter that has an adverse affect on air, water, or soil.
estuarythin zone along a coastline where freshwater system(s) and river(s) meet and mix with a salty ocean (such as a bay, mouth of a river, salt marsh, lagoon).
flow rightsAccess to a particular volume of water in time and space.
biospherethe earth and all its ecosystems.
photosynthesisThe manufacture by plants of carbohydrates and oxygen from carbon dioxide and water in the presence of chlorophyll, using sunlight as an energy source.
crest line or widthThe distance from one stream bank to the other along the crest of a waterfall.
drainage basinan area of land where all water drains into a central water body
absorptionThe process in which incident radiant energy is retained by a substance
icingMasses or sheets of ice formed on the frozen surface of a river or floodplain
mesolowA small scale low pressure center, ranging from the size of an individual thunderstorm to many tens of miles.
oxbow lakea U shaped remnant of a part of a meander which forms a lake
fill periodThe spring period of lessening runoff, when reservoirs are filled at a rate designed to maintain flood storage and reach targeted summer pool elevations
biodiversitythe variety of plant, animal, and microorganism species present in the ecosystem and the community structures the form.
acid rainRainfall with a pH of less than 7.0
biotaCollectively, the plants, microorganisms, and animals of a certain area or region.
evaporationThe process by which atoms or molecules in a liquid state gain sufficient energy to enter the gaseous state (usually with a heat catalyst).
lagoona shallow pond where sunlight, bacterial action, and oxygen work to purify wastewater
environmentThe sum of all external influences and conditions affecting the life and development of an organism or ecological community; the total social and cultural conditions.
distribution coefficentalso called partition coefficient
stormwaterStormwater is the surface water runoff that occurs after rain
slickensidesa smooth striated polished surface produced on rock by movement along a fault.
return flowThe portion of withdrawn water not consumed by evapotranspiration or system losses that returns to its source or to another body of water.
bankfull widthThe width of a river or stream channel between the highest banks on either side of a stream.
limestonerock that consists mainly of calcium carbonate and is chiefly formed by accumulation of organic remains.
cyanobacterialPredominantly photosynthetic prokaryotic organisms containing a blue pigment in addition to chlorophyll; occur singly or in colonies in diverse habitats; important as phytoplankton.
metallorganica compound that possesses carbon but no direct M-C bond i.e
chuteA very steep cascade that is confined to a narrow channel.
mineralizationThe process whereby concentrations of minerals, such as salts, increase in water, often a natural process resulting from water dissolving minerals found in rocks and soils through which it flows.
ec unitsElectrical conductivity is a measure of the physical ability of a sample to carry an electric current
storm tracksThe path or tracks generally followed by a cyclonic disturbance.
surface waterwater that flows in streams and rivers and in natural lakes, in wetlands, and in reservoirs constructed by humans.
infiltrationThe movement of water through the soil surface into the soil.
plan position indicatorAlso known as a PPI Scope, it is a radar indicator scope displaying range and azimuth of targets in polar coordinates.
digital terrain modelA data model that attempts to provide a three dimensional representation of a continuous surface
river milesGenerally, miles from the mouth of a river to a specific destination or, for upstream tributaries, from the confluence with a main river to a specific destination.
boulderRock fragment whose diameter is greater than 250 mm.
waterloggingsaturation of soil with irrigation water so the water table rises close to the surface.
snow squallA heavy snow shower accompanied by sudden strong winds, or a squall.
apiaristsThose involved in the production of honey.
assimilationThe incorporation (or conversion) of nutrients and contaminants into the ecosystem.
gaining streamA stream or reach of stream whose flow is being increased due to an inflow of ground water.
morainethe leftover matter - usually rock and debris from a glacier
bankThe rising ground bordering a lake or river, or forming the edge of a cut or hollow.
transpirationAn essential physiological process in which plant tissues give off water vapor to the atmosphere.
retrogressionIn meteorology, it is the movement of a weather system in a direction opposite to the direction of the basic flow in which it is embedded
landscape featuresThe land, water, vegetation, and structures that compose the characteristic landscape.
bank-full dischargeThe stream discharge corresponding to the water stage that first overtops the natural banks
bedBottom of a channel bounded by banks.
annular spacethe space between two concentric cylindrical objects, one of which surrounds the other, such as the space between the walls of a drilled hole and a casing.
absorptionthe uptake of water, other fluids, or dissolved chemicals by a cell or an organism (as tree roots absorb dissolved nutrients in soil).
creel census surveyThe collection of data concerning the number of fish caught by sport fishers on a particular stream or in a particular area.
operable unita term used by the Superfund program to describe a discrete action that comprises an incremental step toward comprehensively addressing site problems
water rightA legally protected right to take possession of water occurring in a natural waterway and to divert that water for beneficial use.
extractionWater taken from rivers for off-stream use or consumption.
sewageThe waste and wastewater produced by residential and commercial sources and discharged into sewers.
macroinvertebratesInvertebrates with a body greater than 1 mm that is, that can be seen with the naked eye.
base line or widthThe distance from one stream bank to the other along the base of a waterfall.
hydrologyThe study of the properties, movement and behavior of water on the land surface and under ground.
dockA place for vessels to load and unload cargo or to be repaired.
index fishing programprogram of annual netting used to estimate fish population size
sucker mouthtube-like mouth which sucks prey into their jaw
average year water demandDemand for water under average hydrologic conditions for a defined level of development.
rain rejectionOccurs when water ordered from a dam by an irrigator is not then taken from the river, or is returned to the river because of rain in the meantime.
forbA non-grass herbaceous plant.
purgeto force a gas through a water sample to liberate volatile chemicals or other gases from the water so their level can be measured.
tropopauseThe boundary zone or transition layer between the troposphere and the stratosphere
overdraftpumping water from a groundwater basin or aquifer in excess of the supply flowing into the basin; results in a depletion or "mining" of the groundwater in the basin.
biofilmA gelatinous sheath of algae and micro-organisms, including benthic algae and bacteria, formed on surfaces such as gravel, sediment and plants (ARMCANZ & ANZECC 2000).
upwellingThe process by which water rises from a lower to a higher depth, usually as a result of divergence and offshore currents
ionosphereA complex atmospheric zone of ionized gases that extends between 50 and 400 miles (80 to 640 kilometers) above the earth's surface
cobbleSubstrate particles that are smaller than boulders and are generally 64-256 mm in diameter
fill(1) (Geology) Any sediment deposited by any agent such as water so as to fill or partly fill a channel, valley, sink, or other depression
natural resourceany form of matter or energy obtained from the environment that meets human needs.
threatened speciesUnder the Federal Endangered Species Act, animal populations may be determined to be either threatened or endangered
condensationsublimation,       vapourization, transpiration, evapotranspiration, volatilization).
runoutThe horizontal distance from the crest to the base of a waterfall.
depositionAccumulation of sediment on the channel bed or banks.
conductivityA measure of the amount of salts dissolved in water.
solubilitythe amount of mass of a compound that will dissolve in a unit volume of solution.
propagulesAny part of an organism, produced sexually or asexually, that is capable of giving rise to a new individual.
heightThe vertical distance from the base to the crest of a waterfall.
lunetteA wind-formed, half-moon shaped crescent, usually of sand or fine sediment.
analytical watershedFor planning purposes, a drainage basin subdivision used for analyzing cumulative impacts on resources.
biological integritythe ability to support and maintain balanced, integrated functionality in the natural habitat of a given region
rehabilitationTo restore to a former state or capacity
springan issue of water from the earth; a natural fountain; a source of a body or reservoir of water.
channel patternAspect of a stream channel in plan view, with particular reference to the degree of sinuosity, braiding, and anabranching.
mouthThe mought is the end of a river, where it empties into a large body of water.
urban runoffStorm water from city streets and gutters that usually contains a great deal of litter and organic and bacterial wastes into the sewer systems and receiving waters.
fall velocityVelocity at which a sediment particle falls through a column of still water.
eddyA circular current of water, usually resulting from an obstruction.
confluenceThe meeting or junction of two or more streams.
detergentsynthetic washing agent that helps remove dirt and oil
greenhouse effectThe overall warming of the earth's lower atmosphere primarily due to carbon dioxide and water vapor which permit the sun's rays to heat the earth, but then restrict some heat-energy from escaping back into space.
nmr spectroscopyis a spectroscopic technique to identify functional groups and structure of a compound
bed slopeInclination of the channel bottom.
leapA single vertical, or very near vertical, fall of water.
populationThe number of people living in a certain area.
fecal coliformthe portion of the coliform bacteria group which is present in the intestinal tracts and feces of warm-blooded animals
lag timethe time from the center of a unit storm to the peak discharge or center of volume of the corresponding unit hydrograph.
perfected water righta water right which indicates that the uses anticipated by an applicant, and made under permit, were made for beneficial use
capacity building programA holistic approach to knowledge building and transfer, which fosters skill development, competency, innovation and confidence
habitatThe type of environmental in which a given plant or animal lives and grows, including physical and biological conditions.
snagAny standing dead, partially dead, or defective (cull) tree at least 10 inches in diameter at breast height and at least 6 feet tall.
capillary zonesoil area above the water table where water can rise up slightly through the cohesive force of capillary action
homogeneousis a system that consists of only one phase i.e
apogeeThe point farthest from the earth on the moon's orbit
fryrecently emerged fish, after the yolk sac has been absorbed
bridge ownerAny Federal, State, Local agency, or other entity responsible for a structure defined as a highway bridge by the National Bridge Inspection Standards (NBIS).
coagCouncil of Australian Governments-the peak intergovernmental forum in Australia, comprising the Prime Minister, state premiers, territory chief ministers and the President of the Australian Local Government Association.
fallsThe sudden descent of a stream primarily over a vertical or extremely steep section of its stream bed
diversionThe transfer of water from a stream, lake, aquifer, or other conduit to another watercourse or to the land, as in the case of an irrigation system.
stream reachAn individual segment of stream that has beginning and ending points defined by identifiable features such as where a tributary confluence changes the channel character or order.
windfallTrees or parts of trees felled by high winds.
core areaThe area of habitat essential in the breeding, nesting, and rearing of young, up to the point of dispersal of the young.
meander loopIndividual loop of a meandering or sinuous stream lying between inflection points with adjoining loops.
herbicidea chemical used to kill nuisance plants
freezing rainRain that falls as liquid and freezes upon impact to form a coating of glaze on the colder ground or other exposed surfaces
anaerobicalso refers to metabolic activities, glycolysis, in the       absence of oxygen which occurs in some microorganisms.
biomassThe total dry weight of all organisms in a particular sample, population, or area.
irrigationThe supply of water to farmland so that crops can grow in areas wherewater supplies are scarce or unreliable
hydrologic balanceAn accounting of all water inflow to, water outflow from, and changes in water storage within a hydrologic unit over a specified period of time.
lachrymatora compound that makes the eyes fill with tears but does not damage them (“teargas”)
armour layerAn impermeable surface built up over a period of time by weathering.
anomalous propagationThis refers to the non-standard propagation of a beam of energy, radio or radar, under certain atmospheric conditions, appearing as false (non-precipitation) echoes
eutrophicationThe natural process by which lakes and ponds become enriched with dissolved nutrients, resulting in increased growth of algae and other microscopic plants.
headcuttingThe process by which the stream is actively eroding the streambed downward (degrading, incising, downcutting) to a new base level
dependable supplyThe annual average quantity of water that can be delivered during a drought period.
sedimentation(1) The combined processes of soil erosion, entrainment, transport, deposition, and consolidation
fish laddera stepped fishway with water flowing over it
drawdownthe drop in the water table or level of groundwater when water is being pumped from a well; the amount of water used from a tank or reservoir; the drop in the water level of a tank or reservoir.
biological diversityThe variety of and variability among living organisms and the ecological systems of which they are part, including diversity among species, the variation within species, and the variety of ecosystem functions they provide.
suspended solidsthe small solid particles in water that cause turbidity
canopyA layer of foliage in a forest stand
flowThe amount of water passing a particular point in a stream or river, usually expressed in cubic feet per second (cfs).
overbank flowWater flow over the top of the bankfull channel onto the floodplain.
water quality-based toxics controlan integrated strategy used in NPDES permitting to assess and control the discharge of toxic pollutants to surface waters
grade control structureA weir, dam, sill, drop structure, or other structure used to control erosion in stream channels with steep grades or where the slope has been destabilized.
stabilityThe ability of an instrument or sensor to maintain a consistent output when a constant input is applied over time
littoral zoneThe part of the shoreline that is submerged at high tide and exposed at low tide.
effective precipitationthe part of precipitation which produces runoff; a weighted average of current and antecedent precipitation "effective" in correlating with runoff
downstreamThe direction that the river flows, towards the mouth of the river.
confluenceThe point at which the two streams merge
assimilative capacitythe capacity of a natural body of water to receive and dilute wastewaters or toxic materials without damage to aquatic life or humans who consume the water.
hydrologyThe science of waters of the earth; water's properties, circulation, principles, and distribution.
urban runoffstorm water from city streets and adjacent domestic or commercial properties that carries pollutants of various kinds into the sewer systems and receiving waters.
channelA depression created by constant erosion that carries the stream's flow.
dewaterremove or separate a portion of the water in a sludge or slurry to dry the sludge so it can be handled and disposed; remove or drain the water from a tank, trench, or aquifer.
environmental assessmentA systematic analysis of site-specific activities used to determine whether such activities have a significant effect on the quality of the human environment and whether a formal environmental impact statement is required; and to aid an agency's compliance with the National Environmental Policy Act when no environmental impact statement is necessary.
water velocitythe speed at which the river or stream is flowing
freshetA rapid temporary increase in stream flow due to heavy rains or snow melt.
prevailing windA wind that blows from one direction more frequently than any other during a given period, such as a day, month, season, or year.
radarsonde observationAn upper air observation used to determine winds and other meteorological data, by tracking the range, elevation, and azimuth of a radar target carried aloft
watercoursesA river, stream or creek in which water flows in a natural channel, whether permanently or intermittently.
hydraulic actionThe force of the water wears away the river bank from underneath
erosionThe wearing away of rock or soil by the action of water, wind, ice or other mechanical or biological forces.
water cyclenatural pathway water follows as it changes between liquid, solid, and gaseous states; biogeochemical cycle that moves and recycles water in various forms through the ecosphere
refractive indexis a physical property that quantifies the refraction of light by a solid or liquid
phenolphthalein alkalinitythe alkalinity in a water sample measured by the amount of standard acid needed to lower the pH to a level of 8.3 as indicated by the change of color of the phenolphthalein from pink to clear.
ultravioletElectromagnetic radiation that has a wavelength shorter than visible light and longer than x-rays
anoxicWithout oxygen.
turbulenceThe irregular and instantaneous motions of air which is made up of a number of small of eddies that travel in the general air current
physiographic provincean area with similar characteristics based on geology, soil type, and topography.
metalsThese are elements such as iron, manganese, copper, lead and zinc
low-flow specialistsFlora and/or fauna that recruit and thrive in low flow conditions.
recurrence intervalaverage amount of time between events of a given magnitude
overcastThe amount of sky cover for a cloud layer that is 8/8ths, based on the summation layer amount for that layer.
dischargethe amount of water flowing past a given point on a stream; measured in cubic feet or cubic metres per second
biologicalRelating to any living organism either plant, animal, fungus or virus.
geomorphologyThe study of present day landforms.
sedimentationDeposition of sediments in lakes or other areas of relatively still water
droughtalthough there is no universally accepted definition of drought, it is generally the term applied to periods of less than average precipitation over a certain period of time
siltSubstrate particles smaller than sand and larger than clay (3 to 60 um).
ecosystemA system formed by the interaction of a group of organisms and their environment.
oligomeris a polymer or polymer intermediate containing relatively few structural units (more than two units) i.e
riparian areathe border of the stream above its banks; wet soil areas influenced by the water of a stream, lake, or wetland
cut bankThe outside bank of a bend, often eroding opposite a point bar.
scourprocess of water eroding material through high velocities in conjunction with moving sediment.
terrestrial vegetationPlants growing on land beyond the flood zone of a river or stream.
erosion control mattingFibrous matting (e.g., jute, paper, etc.) placed or sprayed on a streambank for the purpose of resisting erosion or providing temporary stabilization until vegetation is established.
algicidesubstance or chemical used specifically to kill or control algae.
clarificationthe clearing action that occurs during wastewater treatment when solids settle out
sea surface temperatureThe temperature of the water's surface
sludgesolid matter that settles to the bottom of sedimentation tanks in a sewage treatment plant and must be disposed of by digestion or other methods or recycled to the land.
irrigation efficiencyThe efficiency of water application and use
gum-leaf skeletoniserA native Australian moth (Uraba lugens) that primarily feeds on gum leaves.
siltationSiltation is the deposit or accumulation of very tiny soil particles (silt).
conjunctive useThe operation of a groundwater basin in combination with a surface water storage and conveyance system
quenchinga reaction is terminating by deactivating reactive intermediates
general scourGeneral scour is a lowering of the streambed across the stream or waterway at the bridge
ravineAnother name for a narrow gorge.
public water systema system for the provision to the public of water for human consumption through pipes or other constructed conveyances.  In Texas, a public water system is one that serves at least 15 service connections or serve at least 25 individuals at least 60 days out of the year.
extractionis a process to isolate a compound from a mixture by either temporary chemical modification or distribution within two layers.
compensationAn addition of specific materials or devices to counteract a known error.
tceqTexas Commission on Environmental Quality.
calibration bathA uniform temperature enclosure using carefully stirred fluid to provide excellent thermal contact and uniformity for temperature calibration.
samplebacterial       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.
poolA segment where the water is deeper and slower moving.
reservoir levelThe elevation of the water in a reservoir at a given time, measured in feet above sea level.
chromatographyis a technique to separate compounds from each other
footSee Base.
resiliencethe ability of an ecosystem to maintain or restore biodiversity, biotic integrity, and ecological structure and processes following disturbance.
large woody debrisPieces of wood larger than 10 feet long and 6 inches in diameter, in a stream channel.
mooringsThe place where a ship or boat is docked (or tied up)
contractionEffect of channel or bridge constriction on flow streamlines.
coarse woody debrisPortion of a tree that has fallen or been cut and left in the woods
heterogeneousis a system that consists of at least two phases (solid-liquid)
top of gatesThe maximum controlled elevation at a project, typically the top of a spillway gate in a closed position or crest elevation of an uncontrolled outlet structure.
wave energyThe energy generated by coastal surface waves.
combined sewer overflowthe discharge of a mixture of storm water and domestic waste when the flow capacity of a sewer system is exceeded during rainstorms.
femaFederal Emergency Management Agency; The federal agency responsible for dealing with emergency flood conditions and flood insurance.
spot ratioSee Distance to Target Ratio.
midreachesstreams carrying the water from several tributaries
headgatethe gate that controls water flow into irrigation canals and ditches
brinehighly salty and heavily mineralized water containing heavy metal and organic contaminants.
detritusDecaying organic matter found on the bottom of a stream or lake, or in the top soil layer.
runoffA general term for water that flows across the landscape after a significant rainfall event
evaporationthe changing of water to water vapor
cystophoraType of robust brown algae found on reefs in South Australia.
hydrologic cycleOften called the water cycle, it is the vertical and horizontal transport of water in all its states between the earth, the atmosphere, and the seas.
instantaneous flowsThe velocity of a volume of water.
dia.Diameter
runoffWater that has from something
hydraulic modela computer model of a segment of river used to evaluate hydraulic conditions
riparianReferring to or relating to areas adjacent to water or influenced by water associated with streams or rivers on geological surfaces.
cross sectionSection normal to the trend of a channel or flow.
convectionThe transfer of heat by the circulation of fluid or gas.
sustained overdraftlong term withdrawal from the aquifer of more water than is being recharged.
katafrontA front where the warm air descends the frontal surface, except in the low layers of the atmosphere.
return flowsurface water that returns to the natural environment after diversion for beneficial uses, such as for irrigation.
bed formsthree-dimensional configurations of bed material, which are formed in streambeds by the action of flowing water.
dominant discharge(A) Discharge of water which is of sufficient magnitude and frequency to have a dominating effect in determining the characteristics and size of the stream course, channel, and bed; (B) discharge which determines the principal dimensions and characteristics of a natural channel
petroleum derivativeschemicals formed when gasoline breaks down in contact with water.
designated useClassification designated in water quality standards for each water body or segment that defines the optimal purpose for that water body.
tragedy of the commonsthe idea that no one takes responsibility for things that everybody owns.
funnel cloudA violent, rotating column of air visibly extending from the base of a towering cumulus or cumulonimbus toward the ground, but not in contact with it
kcfs-monthOne kcfs-month is a flow of 1,000 cubic feet per second for one month or 0.0595 million acre-feet.
toeThe break in slope at the foot of a stream bank where the bank meets the bed.
monomicticlakes and reservoirs that are relatively deep, do not freeze over during winter, and undergo a single stratification and mixing cycle during the year (usually in the fall).
hydraulic jumpAbrubt, turbulent, noisy transition from super-critical flow to sub-critical flow
max/minA common thermometer feature allowing you to quickly display the maximum and/or minimum values measured during a specified period of time.
subcritical flowflow characterized by low velocity and a Froude number less than 1
streamA general term for a body of flowing water; natural water course containing water at least part of the year
bank stabilityThe properties of a stream bank that counteract erosion, for example, soil type, and vegetation cover.
noctilucent cloudsRarely seen clouds of tiny ice particles that form approximately 75 to 90 kilometers above the earth's surface
detention timethe time required for a volume of water to pass through a tank at a given rate of flow; in storage reservoirs, the length of time water will be held before being used.
rainPrecipitation in the form of liquid water droplets greater than 0.5 mm
lakeAny inland body of standing water, usually fresh water, larger than a pool or pond; a body of water filling a depression in the earth's surface.
aerationthe mixing or turbulent exposure of water to air and oxygen to dissipate volatile contaminants and other pollutants into the air.
rock faceThe vertical to very steep section of a stream bed that a waterfall descends
macrophytemacroscopic plants in the aquatic environment
ephemeral streamStream or reach of stream that does not flow for parts of the year
mean velocityThe average cross-sectional velocity of water in a stream channel
bankSides of a channel between which the flow is normally confined.
headwater elevationThe water elevation immediately upstream of a dam.
remediationmethods used to remove or contain a toxic spill or hazardous materials from a Superfund site; a generic term used to describe cleanup activities.
ephemeralAn ephemeral waterbody is a stream, lake or other type of wetland that only contains water for a short period following rainfall, typically for only a few weeks to several months.
snowflakesAn ice crystal or an aggregate of ice crystals which fall from clouds.
pathogensAny virus, bacteria, or fungi that cause disease.
sedgeA plant from the family Cyperaceae
water columnan imaginary column extending through a water body from its floor to its surface
fault blockA plane of fracture in a rock along which displacement has occurred.
relative humidityThe ratio of the actual amount of water vapor (absolute humidity) present in the air to the saturation point at the same temperature, usually expressed as a percentage.
horizonOne of several lines or planes used as reference for observation and measurement relative to a given location on the surface of the earth
severe weatherGenerally, any destructive weather event, but usually applies to localized storms, such as blizzards, intense thunderstorms, or tornadoes.
dropsondeA radiosonde dropped with a parachute from an aircraft rather than lifted by a balloon to measure the atmosphere below.
stratopauseThe boundary zone or transition layer between the stratosphere and the mesosphere
aquatic life usea beneficial use designation in which the water body provides suitable habitat for survival and reproduction of desirable fish, shellfish, and other aquatic organisms.
down logPortion of a tree that has fallen or been cut and left in the woods.
gradientThe rate of change in (vertical) elevation per unit of horizontal distance.
ecosysteman interdependent biological system involving interaction between living organisms and their immediate physical, chemical and biological environment.
daylightIn the restoration field, a verb that denotes the excavation and restoration of a stream channel from an underground culvert, covering, or pipe.
centripetal forceThe force required to keep an object moving in a curved or circular path
retardation factoris the ratio of how far the center of a spot traveled compared to the solvent front (=Rf-value)
conservationThe process or means of achieving recovery of variable populations.
weather vaneOriginally used as a wind vane, it is an instrument that indicates the wind direction
bioaccumulationuptake and retention of substances by an organism from its surrounding medium (usually water) and from food.
buys ballot's lawDescribes the relationship of the horizontal wind direction to the pressure distribution
cut bankThe outside, often eroding, bank on a channel bend
ozoneA nearly colorless gas and a form of oxygen (O2)
ambient background concentrationa representative concentration of the water quality in a receiving water body, determined from monitoring
water table aquiferan aquifer confined only by atmospheric pressure (water levels will not rise in the well above the confining bed).
fluvialMigrating between main rivers and tributaries
mammatocumulusAn obsolete term for cumulonimbus mammatus, it is a portion of a cumulonimbus cloud that appears as a pouch or udder on the under surface of the cloud
anadromous fishfish that migrate from salt water to fresh water for spawning
sinkingcontrolling oil spills by using an agent to trap the oil and sink it to the bottom of the body of water where the agent and the oil are biodegraded.
baetidA type of insect called a mayfly from the family Baetidae.
habitat conservation planAn agreement between the Secretary of the Interior and either a private entity or a state that specifies conservation measures that will be implemented in exchange for a permit that would allow taking of a threatened or endangered species.
twilightOften called dusk, it is the evening period of waning light from the time of sunset to dark
stream morphologyThe form (dimension, pattern and profile) and structure of the stream channel.
monitortrack a characteristic over time, using uniform methods to evaluate change non-point source pollution: pollutants that enter waterways from broad land areas as a result of the way the land is used (e.g
hydricWet.
interbasin transferThe diversion of water from one drainage basin to one or more other drainage basins.
deepeningUsed in describing the history of a low pressure system or an area of cyclonic circulation, it means a decrease in the central pressure of the system
diurnalPertaining to actions or events that occur during a twenty-four hour cycle or recurs every twenty-four hours
melting pointis the temperature at which a solid becomes a liquid, usually reported as a range
stream powerDirectly related to the sediment transport rates of a stream and measured as the loss of potential energy per unit length of stream channel
heterocercal tailshark-like asymmetrical tail
blackwaterWater that contains waste of humans, animals or food.
irrigation return flowapplied water that is not transpired, evaporated, or deep-percolated into a groundwater basin but returns to a surface water supply.
sandLoose particles of hard, broken rock or minerals
coronaA pastel halo around the moon or sun created by the diffraction of water droplets
pyrophoricmeans that a compound catches on fire when it comes in contact with air
meander benda windings or sinuous section of a stream channel
katabatic windA wind that is created by air flowing downhill
braided streamA complex tangle of converging and diverging stream channels (Anabranches) separated by sand bars or islands
orogenyperiod of mountain-building.
clarifiera tank in which solids settle to the bottom and are subsequently removed as sludge.
stream powera measure of energy available to move sediment, or any other particle in a stream channel
pressure altitudeThe altitude in standard atmosphere at which a given pressure will be observed
turbidity"The term ""turbid"" is applied to waters containing suspended matter that interferes with the passage of light through the water or in which visual depth is restricted."
ground water reservoirprimarily 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).
water vaporWater in gaseous form
phmeasure of acidity
off-channel areaAny relatively calm portion of a stream outside of the main flow.
permanent wetlandsWetlands that are permanently inundated, as opposed to semi-permanent wetlands, which are inundated periodically and may have long periods of no water inundation.
theodoliteAn optical instrument used to track the motion of a pilot balloon, or pibal, by measuring the elevation and azimuth angles.
runShallow stream section with moderate currents.
pathogenic bacteriacysts 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.
altimeterAn instrument used to determine the altitude of an object with respect to a fixed level
organellesin 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.
underflowmovement of water through subsurface material.
acequiairrigation channels constructed during the period of Spanish Colonial Mission settlement
depth of flowThe height of the water surface above the streambed.
stream profileA view of a stream's course from its headwaters to its mouth, showing the steepness of the descent.
dredgingRemoving material (usually sediments) from wetlands or waterways, usually to make them deeper and wider.
surface waterWater flowing or held in waterways or wetlands on the surface of the landscape.
watchA forecast issued well in advance of a severe weather event to alert the public of the possibility of a particular hazard, such as tornadoes, severe thunderstorms, flash and river floods, winter storms, or heavy snows.
overlookA viewing area for a waterfall or a scenic area.
isinglassa sticky substance that is made from swim bladders of fish
sealthe impermeable material, such as cement grout bentonite, or puddling clay placed in the annular space between the borehole wall and the casing of a water well to prevent the downhole movement of surface water or the vertical mixing of artestian waters.
usaceU.S
demandThe numerical expression of the desire for goods and services associated with an economic standard for acquiring them.
allogenic rechargerecharge that occurs in a sinking stream, entering an aquifer through sinkholes or fault planes
saltsnutrients, pesticide chemicals or contaminants, are       washed into a lower layer of soil or are dissolved and carried away by water.
floraThe plants of a particular region.
hypersalineCharacteristic of an aquatic environment where the water is much saltier than normal sea water.
meandercurves in the stream channel where the stream dissipates energy.
nonthreshold pollutantsubstance or condition harmful to a particular organism at any level or concentration.
transmissivityrefers to the rate at which limestone allows the transmission of water
groundwaterwater 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.
senescedIncludes vegetation whose leaves have lost most of their nutrients and are dropping from the trees.
short waveA progressive wave of smaller amplitude, wave length, and duration than a long wave
articulated concrete mattressRigid concrete slabs which can move without separating as scour occurs; usually hinged together with corrosion-resistant cable fasteners; primarily placed for lower bank protection.
invertebratean animal without a back bone
bioengineeringThe use of living plants to stabilize soil
point sourcesource of pollution that involves discharge of wastes from an identifiable point, such as a smokestack or sewage treatment plant
eutrophicRich in mineral and organic nutrients that promote a proliferation of plant life, especially algae.
losing streamA stream or reach of stream from which some water flows from the stream bed into the ground.
oligotrophichaving a low supply of plant nutrients
biological diversityThe variety of different species, the genetic variability of each species, and the variety of different ecosystems that they form.
daily meanThe average temperature for a day computed by averaging either the hourly readings or, more commonly, the maximum and minimum temperatures.
debris flowA rapidly moving mass of rock fragments, soil, and mud, with more than half of the particles being larger than sand size.
per capita water useThe water produced by or introduced into the system of a water supplier divided by the total residential population; normally expressed in gallons per capita per day (gpcd).
towering cumulusAnother name for cumulus congestus, it is a rapidly growing cumulus or an individual dome-shaped clouds whose height exceeds its width
kelvin temperature scaleA temperature scale with the freezing point of +273°K (Kelvin) and the boiling point of +373° K
taggedexternal identification, such as a wire or flag which indicates previously captured strugeon
milligrams per literthe weight in milligrams of any substance dissolved in one liter of liquid; nearly the same as parts per million by weight.
dew pointThe air temperature at which, under current barometric pressure, the water vapor currently in the air would condense into water or dew (or reach 100% humidity)
filtera device used to remove solids from a mixture or to separate materials
supersaturatedis a solution that contains more than the maximum amount of solute at a given temperature
groundwater basinA groundwater reservoir, defined by an overlying land surface and the underlying aquifers that contain water stored in the reservoir
meander beltThe area between lines drawn tangential to the extreme limits of fully developed meanders
calcium carbonateCACO3 - a white precipitate that forms in water lines, water heaters and boilers in hard water areas; also known as scale.
consumptive usethe quantity of water not available for reuse
geomorphology/morphologyThat science that deals with the form of the Earth, the general configuration of its surface, and the changes that take place due to erosion and deposition.
meanderSomething that meanders follows a winding path.
flow duration curvea measure of the range and variability of a stream's flow
channel-forming dischargeSee dominant discharge.
bathochromic shiftis a shift to higher wavelength in the UV-Vis spectrum
runoffThat portion of rainfall or snowmelt that moves across the land surface into streams and lakes.
oxbow lakeA small arc-shaped lake formed when a meander is sealed off by deposition
cooling towerlarge tower used to transfer the heat in cooling water from a power or industrial plant to the atmosphere either by direct evaporation or by convection and conduction.
monitoring and evaluation programDevelopment of monitoring and evaluation activities to determine the success or otherwise of measures put in place as part of stormwater management projects.
specific heatthe amount of heat required to raise the temperature of a kilogram of a substance (water) by 1 degree Celsius.
moisture contentthe amount of water lost from soil upon drying to a constant weight, expressed as the weight per unit of dry soil or as the volume of water per unit bulk volume of the soil.
convectionMotions in a fluid that transport and mix the properties of the fluid
refugiaPlaces of shelter from danger or pursuit
average annual runoffFor a specified area, it is the average value of annual runoff amounts calculated for a whole hydrologic cycle of record that represents average hydrologic conditions.
imbricatedReference to stream bed sediment particles, having an overlapping or shingled pattern.
reproducibilitySee repeatability.
dispersionthe movement and spreading of contaminants out and down in an aquifer.
launchingRelease of undercut material (stone riprap, rubble, slag, etc.) downslope or into a scoured area.
channel capacityVolume at which a channel spills its bank (see bankfull).
ecosystem(1) Recognizable, relatively homogeneous units, including the organisms they contain, their environment, and all the interactions among them
spring floodA flood that occurs in spring months, in the southern hemisphere corresponding to the months of September, October and November.
sarocSan Antonio River Oversight Committee; a twenty-two member citizen committee appointed in 1998 to guide the planning and implementation of the San Antonio River Improvements Project.
dry washA streambed that carries water only during and immediately following rainstorms.
infiltrationpaving, 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.
hatch boxA device used to incubate relatively small numbers of eggs
riffleA reach of stream that is characterized by shallow, fast-moving water broken by the presence of rocks and boulders.
barragea construction across the mouth of a river that prevents the entry of seawater; behind a barrage' the water is fresh.
resourceA person, thing, or action needed for living or to improve the quality of life.
tributarya stream that contributes its water to another stream or body of water.
catalystis a compound that increases the rate of the reaction by lowering the activation energy for a chemical reaction, but does not change the yiel
pavingCovering of stones on a channel bed or bank (used with reference to natural covering).
bed materialMaterial found in and on the bed of a stream (May be transported as bed load or in suspension).
tilt blockA formation where two geological features tilt or dip around each other to form a depression.
right of capturethe idea that the water under a person's land belongs to that person and they are free to capture and use as much as they want
turbidityA measure of water clarity
cone of depressionnatural depression in the water table around a well during pumping.
auto-offThe ability of a device to turn itself off to conserve power after a specified period of time without any user inputs
interbasin transferThe transfer of water out of one river basin for the benefit of a public water system in another river basin
tributaryA stream or river that feeds into a larger watercourse.
biodiversityThe variability among living organisms from all sources (including terrestrial, marine and other aquatic ecosystems and the ecological complexes of which they are part) and the diversity within and between species and of ecosystems (ARMCANZ & ANZECC 2000).
preservativea chemical added to a water sample to keep it stable and prevent compounds in it from changing to other forms or to prevent microorganism densities from changing prior to analysis.
drizzleSlowly falling precipitation in the form of tiny water droplets with diameters less than 0.02 inches or 0.5 millimeters
ditchA long narrow trench or furrow dug in the ground, as for irrigation, drainage, or a boundary line.
collectorsaquatic invertebrates that feed on fine material
decomposerAny of various organisms (as many bacteria and fungi) that feed on and break down organic substances (such as dead plants and animals).
particle size distributionSee Substrate Analysis.
swalesSmall depressions, natural or artificial, that carry water only after a rainfall.
lakeseparated by the fairly thin thermocline       zone, from the lower, colder, denser zone of water, the hypolimnion.
micro-faunaAny fauna not visible to the naked eye.
steady-state mass balancethe mathematical concept that the sum of upstream pollutant loads, each determined by the product of their concentration times flow, equals a resultant downstream load after mixing.
lotic-adapted speciesspecies for which all or part of their life history is dependent on flowing water.
deionized waterwater free of inorganic chemicals.
depositionthe laying down of material by erosion or transport by water or air.
groundwater runoffthe portion of runoff which has passed into the ground, has become ground water, and has been discharged into a stream channel as spring or seepage water.
contaminateTo make impure or unclean by contact or mixture.
buffer stripA barrier of permanent vegetation, either forest or other vegetation, between waterways and land uses such as agriculture or urban development, designed to interrupt and filter out pollution before it reaches the surface water resource.
electrofishinga biological collection method that uses electric current to facilitate capturing fishes.
vertical wind profileA series of wind direction and wind speed measurements taken at various levels in the atmosphere that show the wind structure of the atmosphere over a specific location
subpolarThe region bordering the polar region, between 50° and 70° North and South latitude
mouththe point at which a river empties into another body of water
conductionThe trasnfer of electrical energy or heat through or by means of a conductor.
stoneRock or rock fragments used for construction.
perihelionThe point of the earth's orbit that is nearest to the sun
glacierA huge mass of ice, formed on land by the compaction and re-crystallization of snow, that moves very slowly downslope or outward due to its own weight.
current velocitythe velocity of water flow in a stream, measured in units of length per unit of time, such as feet per second (fps).
in-situ strippingtreatment system that removes or strips volatile organic compounds from contaminated groundwater or surface water by forcing an air stream through the water and causing the compounds to evaporate.
secchi discA circular plate, generally about 10-12 in (25.4-30.5 cm) in diameter, used to measure the transparency or clarity of water by noting the greatest depth at which it can be visually detected
point barAn accumulation of alluvium - usually sand or gravel - caused by a decrease in sediment transport capacity on the inside of a meander bend.
irrigation efficiencythe percentage of water applied, and which can be accounted for, in the soil moisture increase for consumptive use.
pressure altimeterAn aneroid barometer calibrated to indicate altitude in feet instead of units of pressure
prognostic chartA chart of forecast predictions that may include pressure, fronts
first flushDescribes situations when contaminants (e.g
meander scrollsLow, concentric ridges and swales on a floodplain, marking the successive positions of former meander loops.
in-channel benchesBench-like formation of sediment formed in the river as a result of flow movement of sediment
isoplethA line connecting equal points of value
riskThe chances of something happening that will have an impact on objectives
barrageany artificial obstruction placed in water to increase water level or divert it
median diameterParticle diameter of the 50th percentile point on a size distribution curve such that half of the particles (by weight, number, or volume) are larger and half are smaller (D50).
endangered speciesone having so few individual survivors that the species could soon become extinct in all or part of its region.
siltSubstrate particles smaller than sand and larger than clay.
morphologythe form, shape, or structure of a stream or organism.
climatic yeara period used in meteorological measurements
bioremediationa process that uses living organisms to remove pollutants.
haloThe ring of light that seems to encircle the sun or moon when veiled by cirrus clouds
constructed wetlandA vegetated detention area designed and built to remove contaminants from stormwater runoff, but which can also provide secondary benefits of habitat enhancement/creation and active and passive recreational and educational opportunities.
average yearly supplyThe average annual supply of a water development system over a whole hydrologic system.
bipolarThe ability of a panel meter to display both positive and negative readings.
hydrolysisthe decomposition of organic compounds by interaction with water.
autogenic rechargerecharge that occurs by falling directly on an aquifer's outcrop at the surface
split-moderefers to the fact that only a small amount of the sample is actually introduced to the GC column
claySubstrate particles that are smaller than silt and generally less than 0.004 mm in diameter.
meltingthe changing of a solid into a liquid.
degradationGeneral and progressive (long-term) lowering of the channel bed due to erosion, over a relatively long channel length.
shearForce parallel to a surface as opposed to directly on the surface
undertowthe current beneath the surface that sets seaward or along the beach when waves are breaking on the shore.
afterbayA reservoir that regulates fluctuating discharges from a hydroelectric power plant or a pumping plant.
spillwayA channel or passageway around or over a dam through which water is released, or “spilled,” past the dam without going through the turbines
potentiometric surfacethe surface to which water in an aquifer can rise by hydrostatic pressure
streama general term for a body of flowing water.
aerobiclife or processes that require, or are not destroyed by, the presence of oxygen.
high cloudsA term used to signify cirriform clouds that are composed of ice crystals and generally have bases above 20,000 feet
boulder windA local name referring to an extremely strong downslope wind in the Front Range of the Rocky Mountains near Boulder, Colorado.
cerclaComprehensive Environment Response, Compensation and Liability Act
water quality criteriascientifically derived ambient limits developed and updated by EPA, under section 304(a)(1) of the Clean Water Act, for specific pollutants of concern
hydraulic modellingNumerical modelling to simulate the hydraulics of a river and predict water surface profiles based on cross-sections, a long profile and a roughness coefficient (simple model) or simulating three dimensional-flow complexities.
irrigationThe controlled application of water to cropland, hayland, and/or pasture to supplement that supplied through nature.
runoffwater that runs off the soil surface
cycloneAn area of closed pressure circulation with rotating and converging winds, the center of which is a relative pressure minimum
floodplain benchA small level area that forms at the effective discharge stage within an over-wide, entrenched channel.
litreThe basic unit of measurement for volume in the metric system; equal to 61.025 cubic inches or 1.0567 liquid quarts.
nematodesAlso called round worms, they are thin, long worm-like animals with tapering ends that lack segments and appendages.
siltationthe process of becoming clogged by fine sediments
stable/stabilityOccurs when a rising air parcel becomes denser than the surrounding air
fascineMatrix of willow or other natural material woven in bundles and used as a filter
hyporheicA region of saturated sediments beneath and beside the active channel that contains some proportion of surface water.
bifurcateDivision or a fork, often represented by two branches splitting from one.
macroalgaeLarge aquatic photosynthetic plants that can been seen without the aid of a microscope.
thalweg(1) The lowest thread along the axial part of a valley or stream channel
subtropicalThe region between the tropical and temperate regions, an area between 35° and 40° North and South latitude
hydraulicRefers to river surface profiles, including cross section, length and depth.
nutrientas a pollutant, any element or compound, such as phosphorous or nitrogen, that fuels abnormally high organic growth in aquatic ecosystems
geologic controlA local rock formation or clay layer that limits the vertical or lateral movement of a stream at a particular point.
dischargeIn the simplest form, discharge means outflow of water
clayParticle whose diameter is in the range of 0.00024 to 0.004 mm.
flow hazardFlow characteristics (discharge, stage, velocity, or duration) that are associated with a hydraulic problem or that can reasonably be considered of sufficient magnitude to cause a hydraulic problem or to test the effectiveness of a countermeasure.
completionsealing off access of undesireable water to the well bore by proper casing and/or cementing procedures.
wave lengthThe least distance between particles moving in the same phase of oscillation of a wave
confluencewhere two or more bodies of water meet
skyThe vault-like apparent surface against which all aerial objects are seen from the earth.
reachin general, a length of stream with relatively homogenous characteristics.
tundraA tundra is a cold, treeless area; it is the coldest biome.
cavingCollapse of a bank caused by undermining due to the action of flowing water.
ecologyThe study of interrelationships of living organisms to one another and to their surroundings.
gaging stationA particular site in a stream, lake, reservoir, etc., where hydrologic data are obtained.
snow crustThe crisp, almost icy, surface on fallen snow, usually formed by the slight melting and refreezing of the surface snow.
dew pointThe temperature to which air must be cooled at a constant pressure to become saturated.
irrigation waterwater which is applied to assist crops in areas or during times where rainfall is inadequate.
variable ceilingOccurs when the height of a ceiling layer increases and decreases rapidly, The ascribed height is the average of all the varying values.
adsorptionthe adhesion of a substance to the surface of a solid or liquid
pentachorophenoltoxic substance usually used as a wood preservative.
heavy waterwater in which all the hydrogen atoms have been replaced by deuterium.
annual floodMaximum flow in 1 year (may be daily or instantaneous).
toxicityThe quantity or degree to which a substance is poisonous or harmful to plant, animal or human health.
finite elementa method of solving the governing equations of a numerical model by dividing the spatial domain into elements in each of which the solution of the governing equations is approximated by a continuous function.
fresh waterwater containing less than 1,000 parts per million (ppm) of dissolved solids of any type
wet bulb thermometerA thermometer used to measure the lowest temperature in the ambient atmosphere in its natural state by evaporating water from a wet muslin-covered bulb of a thermometer
phreatophytesplants that send their roots into or below the capillary zone to use ground water.
pile dikeType of permeable structure for the protection of banks against caving; consists of a cluster of piles driven into the stream, braced and lashed together.
confined aquiferA water-bearing subsurface stratum that is bounded above and below by formations of impermeable soil or rock.
samplingSampling creeks and lakes to assess ecological condition involves visiting a site to count and identify macroinvertebrate species, observe the presence and extent of all major plant types, measure water clarity, assess sediment condition, and collect water samples for water quality assessment in a laboratory.
flood routingThe process of determining progressively the flood elevation (or flood "wave") at successive points along a stream.
leaf area indexA measure of the total area of leaves, twigs, stems, etc
flood plainthe area often affected by a flood
humusdecayed organic matter in or on the soil
liftsLayers of loose soil
pretreatmentprocesses used to reduce, eliminate, or alter the nature of wastewater pollutants from non-domestic sources before they are discharged into publicly owned treatment works (POTWs).
effluentany substance, particularly a liquid, that enters the environment from a point source
endemismthe characteristic of being confined to or indigenous in, a certain area or region.
coagulationin water treatment, the use of chemicals to make suspended solids gather or group together into small flocs.
whole-effluent toxicitythe aggregate toxic effect of an effluent measured directly by a toxicity test.
heat strokeIntroduced to the body by overexposure to high temperatures, particularly when accompanied by high humidity
alluviumsediments deposited by erosional processes, usually by streams.
deflationA process whereby finer silts and clays are removed by the action of wind over geological time.
water pollutionGenerally, the presence in water of enough harmful or objectionable material to damage the water quality.
phytoplanktonPlant plankton.
routing parameterscoefficients that, along with mathematical routing equations, can be used to estimate the attenuation and lag (time delay) associated with the movement of flow through a length of stream channel.
tropics/tropicalThe region of the earth located between the Tropic of Cancer, at 23.5 degrees North latitude, and the Tropic of Capricorn, at 23.5 degrees South latitude
plateauA plateau is a large, flat area of land that is higher than the surrounding land.
disproportionationrefers to the transformation of a substance into two or more dissimilar substances usually by simultaneous oxidation and reduction i.e
hard waterWater high in multivalent cations, such as calcium and magnesium
acidicthe condition of water or soil that contains a sufficient amount of acid substances to lower the pH below 7.0.
concentrationamount of a chemical or pollutant in a particular volume or weight of air, water, soil, or other medium.
planned environmental waterPlanned environmental water to encompass ‘rules based' environmental water, that is, planned environmental water may be delivered through flow rules which specify flows that must be released from storages for environmental purposes.  It may also be delivered or retained through restrictions upon the taking of water.  Planned environmental water may replicate natural flow patterns taking into account the timing, frequency and variability of flows.  Planned environmental water may seek to achieve specific environmental outcomes such as maintaining the success of bird breeding events in specific wetlands, or may be aimed at maintaining general river health through passing flows or end-of-system flow targets.
objectivesSpecific statements about what a project intends to achieve.
gabionBasket or compartmented rectangular container made of wire mesh
gabionsRock-filled wire baskets (generally square) that are stacked together to reinforce an eroding stream bank.
iceThe solid form of water
backwater curveLongitudinal profile of the water surface in a stream where the water surface is raised above its normal level by a natural or artificial obstruction.
poolA deep, usually wide, section of stream with slow currents at low flow
secchi discA circular plate, generally about 10-12 inches (25.4-30.5 cm) in diameter, used to measure the transparency or clarity of water by noting the greatest depth at which it can be visually detected
carrying capacitynumber of organisms a habitat can support throughout a year without damaging organisms or habitat
cascadeA short, steep drop in streambed elevation often marked by boulders and agitated white water.
aquaductA pipe or conduit made for bringing water from a source.
jack fieldRows of jacks tied together with cables, some rows generally parallel with the banks and some perpendicular thereto or at an angle
suspended loadspecific sediment particles maintained in the water column by turbulence and carried with the flow of water.
aspiratoris a device that produces vacuum by means of the Venturi effect
autochthonoous materialOrganic material produced in the stream usually through primary production.
riverine habitatThe aquatic habitat within streams and rivers.
barrier netA net system that is placed across a river, stream or channel to block the passage of fish from dam turbine intakes or other hazards without blocking the water flow.
irrigation diversionGenerally, a ditch or channel that deflects water from a stream channel for irrigation purposes.
algaesimple plants, mostly microscopic without roots and leaves.
sedimentThe organic material that is transported and deposited by wind and water.
depositionA river lays down or drops the sediment or material that it is carrying such as sand, mud, and small stones or sticks
altitudeHow high a place is above sea level.
filter blanketLayer of graded sand and gravel laid between fine‑grained material and riprap to serve as a filter.
catchmentAnother term for Watershed commonly used in Canada and Europe.
microhabitatzones of similar physical characteristics within a mesohabitat unit, differentiated by aspects such as substrate type, water velocity, and water depth.
bathymetricrelated to the measurement of water depth within a water body.
water availability modela numerical surface water flow model used to determine the availability of surface water for water right permitting.
biotathe plant (flora) and animal life (fauna) of a region or ecosystem.
humboldt currentAlso known as the Peru Current, this ocean current flows northward along the western side of South America, offshore Chile and Peru
downgradientthe direction that groundwater flows; similar to "downstream" for surface water.
organism abundance and conditionthat portion of an Index of Biotic Integrity that is a metric measuring species abundance and condition, including proportion of individuals as hybrids and proportion of individuals with disease, tumors, physical damage, or physical anomalies.
bellot windsRefers to the winds in the Canadian Arctic that blow through the narrow Bellot Strait between Somerset Island and the Boothia Peninsula, connecting the Gulf of Boothia and Franklin Strait.
bright bandA narrow, intense radar echo due to water-covered ice particles at the melting level where reflectivity is at its greatest.
erosionThe wearing down or washing away of the soil and land surface by the action of water, wind, or ice.
acre-footA quantity or volume of water covering 1 acre to a depth of 1 ft; equal to 43,560 ft3 or 325, 851 gal.
acid rainrainwater carrying acidic atmospheric pollutants (nitrous or sulfuric oxides)
scatteredThe amount of sky cover for a cloud layer between 3/8ths and 4/8ths, based on the summation layer amount for that layer.
repeatabilityThe ability of an instrument to reproduce the same output reading when the same input value is applied to it consecutively (measuring the same temperature)
forkthe place where two rivers meet
acre-footThe volume of water that will cover one acre to a depth of 1 foot.
pileElongated member, usually made of timber, concrete, or steel, that serves as a structural component of a river‑training structure.
constrictionNatural or artificial control section, such as a bridge crossing, channel reach or dam, with limited flow capacity in which the upstream water surface elevation is related to discharge.
groundwater reservoiran aquifer or aquifer system in which ground water is stored
flashy streamStream characterized by rapidly rising and falling stages, as indicated by a sharply peaked hydrograph
dissolved organic compoundsCarbon substances dissolved in water.
permafrostPerennially frozen layer in the soil, found in alpine, arctic, and antarctic regions.
peak flowthe maximum volume of water that is carried in the river over a certain period of time, expressed in cubic feet per second (cfs)
monitoringThe collection of data by various methods for the purpose of understanding natural systems and features, evaluating the impacts of development proposals on such systems, and assessing the performance of mitigation measures.
interfacial tensionthe strength of the film separating two immiscible fluids (e.g., oil and water) measured in dynes per, or millidynes per, centimeter.
functional feeding groupsclassification of aquatic invertebrates by their feeding method
hydroelectric plantelectric power plant in which the energy of falling water is used to spin a turbine generator to produce electricity.
seedingis a technique to initiate crystallization from saturated or super-saturated solutions
flow regimethe pattern of flow in a river which can be described in terms of the quantity and variability of water flows.
oxbow lakeAn oxbow lake is a stagnant lake that is formed alongside a winding river when the river changes path because of soil erosion, leaving an abandoned stream channel, cut off from the rest of the river.
aciddonate 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).
enrichmentthe addition of nutrients such as nitrogen and phosphorous from wastewater effluent or agricultural runoff to surface water
filtrationthe mechanical process which removes particulate matter by separating water from solid material, usually by passing it through sand.
sediment loadthe amount of sediment carried by a stream
mixed liquora mixture of activated sludge and water containing organic matter undergoing treatment in an aeration tank.
abatementReducing the degree or intensity of, or eliminating, pollution.
riffleModerately swift water with ripples and small rolling waves caused by the slight increase in the steepness of, or an obstruction in, a stream bed.
climategeneralized weather at a given place on earth over a fairly long period; a long term average of weather
lindanea pesticide that causes adverse health effects when present in domestic water supplies and is toxic to freshwater fish and aquatic life.
thermometerAn instrument used for measuring temperature
greenwayA strip of undeveloped land near an urban area, set aside for recreational use or environmental protection.
solar eclipseAn eclipse of the sun occurs when the moon is in a direct line between the sun and the earth, casting some of the earth's surface in its shadow
diablo windsDry winds in the Diablo mountain range in central California that can exceed 60 miles per hour
siltationthe deposition of soil particles moved by the river caused by an obstruction to the river's flow or lower flow velocity.
gray waterWastewater from a household or small commercial establishment that specifically excludes water from a toilet, kitchen sink, dishwater, or water used for washing diapers.
impaired water bodya water body that has been determined under state and federal law as not meeting water quality standards, or having the potential to do so in the future.
trajectoryThe curve that a body, such as a celestial object, describes in space
chokingExcessive constriction of flow which may cause severe backwater effect.
cold waveA rapid fall in temperature within twenty-four hours to temperatures requiring substantially increased protection to agriculture, industry, commerce, and social activities
rechargeThe process by which rain, snowmelt or surface water infiltrates and replenishes ground water reserves.
flood forecastingPrediction of stage, discharge, time of occurrence, and duration of a flood, especially of peak discharge at a specified point on a stream, resulting from precipitation and/or snowmelt.
saturated zonethe area below the water table where all open spaces are filled with water under pressure equal to or greater than that of the atmosphere.
cut-off lowA closed cold core low completely removed from the primary westerly flow
thermocoupleThe sensor of a thermoelectric thermometer, consisting of electrically conducting circuit elements of two different thermoelectric characteristics joined at a junction.
hydrologic balancean accounting of all water inflow to, water outflow from, and changes in water storage within a hydrologic unit over a specified period of time.
alkalinesubstance with pH greater than 7.0; alkalinity is caused by high concentrations of hydroxyl ions; basic
jackDevice for flow control and protection of banks against lateral erosion consisting of three mutually perpendicular arms rigidly fixed at the center
ice fogFog that is composed of minute ice particles
dropA single vertical, or very near vertical, fall of water
in-situ flushingintroduction of large volumes of water, at times supplemented with cleaning compounds, into soil, waste, or groundwater to flush hazardous contaminants from a site.
evapotranspirationThe combination of water that is evaporated and transpired by plants as a part of their metabolic processes.
leave stripsGenerally narrow bands of forest trees that are left along streams and rivers to buffer aquatic habitats from upslope forest management activities.
angler-dayThe time spent fishing for any part of a day by one person.
hydrologic cycleThe constant circulation of water from the sea to the atmosphere, to the land and back to the sea by surface, underground and atmospheric pathways.
clarityThe observed clearness of the water.
macroinvertebrateInvertebrates visible to the naked eye, such as insect larvae and crayfish.
debris flowA rapid moving mass of rock fragments, soil, and mud, with more that half of the particles being larger that sand size.
drought refugesDrought refuges are places that sustain life during the dry seasons, particularly in ephemeral streams.
continentA large land mass rising abruptly from the deep ocean floor, including marginal regions that are shallowly submerged
dry wellA portable calibration furnace that uses narrow metal enclosures rather than liquid to generate uniformity at thermal contact for pre-set temperatures.
overflow rateone of the guidelines for design of the settling tanks and clarifiers in a treatment plant.
blowing dustDust that is raised by the wind to heights of six feet or greater
sloughingMovement of a mass of soil down a bank into the channel (also called slumping)
bed loadSediment that is transported in a stream by rolling, sliding, or skipping along the bed or very close to it; considered to be within the bed layer (contact load).
reference site/reachA minimally impaired site that is representative of the expected or desired ecological conditions and integrity of other sites in the region.
bed formRecognizable relief feature on the bed of a channel, such as a ripple, dune, plane bed, antidune, or bar
macroinvertebratesStream-dwelling arthropods (insects, crustaceans) without a backbone that can be viewed without magnification
coliform bacteriaA group of bacteria used as an indicator of sanitary quality in water
springThe point at which a stream emerges from an underground course through unconsolidated sediments or through caves
overbankWater flow over the top of bank.
interstate wateraccording to law, interstate waters are defined as (1) rivers, lakes and other waters that flow across or form a part of state or international boundaries; (2) waters of the Great Lakes; (3) coastal waters whose scope has been defined to include ocean waters seaward to the territorial limits and waters along the coastline (including inland streams) influenced by the tide.
attenuationthe process whereby the magnitude of a flood event is reduced by slowing, modifying, or diverting the flow of water.
shreddersaquatic invertebrates that feed on leaves or twigs that fall into a stream
sea breezeA diurnal coastal breeze that blows onshore, from the sea to the land
colonially nestingColonial birds nest in the same place at the same time, and coloniality has been a successful evolutionary strategy for many bird species.
micro-organismany organism not visible to the naked eye, for example, bacteria.
stationary phaseis a term used in chromatography
flowthe rate of water discharged from a source expressed in volume with respect to time.
habitat diversityThe number of different types of habitat within a given area.
hi/low alarmA feature common to thermometers that will alert you via visual and/or audible cues (or, in some cases, email or texts) when a measurement is outside user-specified limits for safety or desirability
benthic invertebratesAquatic animals without backbones that dwell on or in the bottom sediments of fresh or salt water
supercritical flowflow characterized by high velocity and a Froude number greater than 1
streamriver 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.
boga type of wetland that accumulates appreciable peat deposits
watershed restorationImproving current conditions of watersheds to restore degraded habitat and provide long-term protection to aquatic and riparian resources.
bar screenin wastewater treatment, a device used to remove large solids from the incoming wastewater stream.
swaleSmall depressions, natural or artificial, that carry water only after a rainfall.
pascal's lawWhen an external pressure is applied to any confined fluid at rest, the pressure is increased at every point in the fluid by the amount of external pressure applied
conduita natural or artificial channel through which fluids may be conveyed.
ceilometerAn instrument that is used to measure the angular elevation of a projected light on the base of a cloud
dischargeVolume of water flowing past a given point in a stream per unit time, typically reported in cubic feet per second.
time zoneAn area using the same standard of time.
condensation pointis the temperature at which the conversion of a substance from the vapor state to a denser liquid or solid state takes place usually initiated by a reduction in temperature of the vapor
jetteaua jet of water.
environmental impact statementA formal document to be filed with the Environmental Protection Agency that considers significant environmental impacts expected from implementation of a major federal action.
sedimentationa large scale water treatment process where heavy solids settle out to the bottom of the treatment tank after flocculation.
bank-full channel widthThe top surface width of a stream channel when flowing at a bank-full discharge.
heat waveA period of abnormally and uncomfortably hot weather
rivera natural stream of water of considerable volume.
manning's "n"Manning's n-value is a coefficient used to describe boundary roughness of a channel or pipe
oceansuch 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.
topographySurface height, in this case refers to land surface height or relief.
snowFrozen precipitation in the form of white or translucent ice crystals in complex branched hexagonal form
pressuresAquatic ecosystem condition reports include the pressures (ie issues that cause potential decline in ecosystem condition)
river continuum  a conceptual model explaining changes in composition of aquatic invertebrate communities in streams and rivers
indian summerA period of abnormally warm weather in mid to late autumn with clear skies and cool nights
ecklonia radiata Is commonly known as kelp and is an example of robust brown algae.
point barThe convex side of a meander bend that is built up due to sediment deposition.
breakA horizontal interruption in the drop of a waterfall.
saturated solutionis a solution that contains the maximum amount of solute at a given temperature.
conservationThe continuing protection and management of natural resources in accordance with principles that assure their optimum long-term economic and social benefits.
control pointThe temperature at which a system is to be maintained.
evapotranspirationThe total amount of water that is transferred from the earth's surface to the atmosphere
aquiferan underground layer of soil, rock or gravel able to hold and transmit water.
hygroscopicis a compound that absorbs water from the air or a solution, nature of drying agents
spawninglaying and fertilizing eggs spawning habitat: parts of a stream or lake that provide suitable areas for fish to spawn; usually gravel beds
washingis a process to remove small amounts of byproducts or a catalyst from a reaction mixture.
lakeAn inland body of standing water deeper than a pond, an expanded part of a river, a reservoir behind a dam.
gully reclamationuse of small dams of manure and straw; earth, stone,or concrete to collect silt and gradually fill in channels of eroded soil.
resilience  Resilience is defined as "the capacity of an ecosystem to tolerate disturbance without collapsing into a different state that is controlled by a different set of processes
ecosystemAn interdependent biological system involving interaction between living organisms and their immediate physical, chemical and biological environment.
vernal equinoxTaking place in the Northern Hemispheric spring, it is the point at which the ecliptic intersects the celestial equator
environmental indicatora measurement, statistic or value that provides evidence of the effects of environmental management programs or of the state or condition of the environment.
groundwater prime supplyLong-term average annual percolation into major groundwater basins from percolation into major groundwater basins from precipitation falling on the land and from flows in rivers and streams.
dewCondensation in the form of small water drops that forms on grass and other small objects near the ground when the temperature has fallen to the dew point, generally during the nighttime hours.
thermometerAn instrument used to measure temperature.
biomonitoringa test used to evaluate the relative potency of a chemical by comparing its effect on a living organism with the effect of a standard population on the same type of organism.
centigradeA temperature scale based on 100 degrees of difference between the freezing and boiling points of water
foodweba model structure used to represent the links between organisms within an environment, based upon the order in which various organisms consume one another.
mudA soft, saturated mixture mainly of silt and clay.
profundal zonea lake's deep-water region that is not penetrated by sunlight.
soluteany substance derived from the atmosphere, vegetation, soil, or rock that is dissolved in water.
wetted perimeterThe line on which the stream's surface meets the channel walls.
rain gageany instrument used for recording and measuring time, distribution, and the amount of rainfall.
rainwater drops which fall to the earth from the air.
bonn conventionThe Bonn Convention was established to protect those species of wild animals that migrate across or outside national boundaries
secondary treatmentsecond step in most waste treatment systems, in which bacteria break down the organic parts of sewage wastes; usually accomplished by bringing the sewage and bacteria together in trickling filters or in the activated sludge process
river channelsLarge natural or artificial open streams that continuously or periodically contain moving water, or which form a connection between two bodies of water.
bridge scourExcessive erosion of the stream banks and bottom below a bridge as a result of the concentration and direction of streamflow.
stable channelA stream channel with the right balance of slope, planform, and cross section to transport both the water and sediment load without net long-term bed or bank sediment deposition or erosion throughout the stream segment.
aggradationGeneral and progressive buildup of the longitudinal profile of a channel bed due to sediment deposition.
temperatureMeasure of how hot or cold it is in an area.
ptc=Phase Transfer Catalysis, utilizes a catalyst which is able to transport an ion from one phase (usually aqueous) into the other phase (organic).
jetterone (as a geyser) that sends out a jet.
wedgePrimarily refers to an elongated area of shallow high pressure at the earth's surface
temperate climateClimates with distinct winter and summer seasons, typical of regions found between the Tropics of Cancer and Capricorn and the Arctic and Antarctic Circles
reynold's numberDimensionless ratio of inertial force to viscous force used to describe the characteristics of fluid flow in a channel or pipe
groutFluid mixture of cement and water or of cement, sand, and water used to fill joints and voids.
evaporationThe process by which a liquid changes to a vapour.
sea level pressureThe atmospheric pressure at mean sea level, usually determined from the observed station pressure.
free ground waterwater in interconnected pore spaces in the zone of saturation down to the first impervious barrier, moving under the control of the water table slope.
hydrologic unitA distinct watershed or river basin defined by an 8-digit code.
undercastIn aviation, it is an opaque cloud layer viewed from an observation point above the layer
channel diversionRemoval of flows by natural or artificial means from a natural length of channel.
carbon exchangeThe process by which carbon is exchanged between the biosphere, geo-sphere, hydrosphere and atmosphere of some habitable body.
methylene chloride=dichloromethane
slopeThe ratio of the change in elevation over distance.
riparian habitatThe aquatic and terrestrial habitat adjacent to streams, lakes, estuaries, or other waterways.
gallonA unit of volume
cascadeA short, steep drop in stream bed elevation often marked by boulders and agitated white water.
flow augmentationIncreased flow from release of water from storage dams.
blizzardA severe weather condition characterized by low temperatures, winds 35 mph or greater, and sufficient falling and/or blowing snow in the air to frequently reduce visibility to 1/4 mile or less for a duration of at least 3 hours
cross-contaminationa condition created when a drill hole, boring, or improperly constructed well forms a pathway for fluid movement between a saturated zone which contains pollutants and a formerly separated saturated zone containing uncontaminated groundwater
hydrographThe graph of stage or discharge against time.
water demand scheduleA time distribution of the demand for prescribed quantities of water for specified purposes
cold vapormethod to test water for the presence of mercury.
hailPrecipitation that originates in convective clouds, such as cumulonimbus, in the form of balls or irregular pieces of ice, which comes in different shapes and sizes
floodThe temporary inundation of normally dry land areas resulting from the overflowing of the natural or artificial confines of the stream channel.
isohyetline that connects points of equal rainfall.
easterliesUsually applied to the broad patterns of persistent winds with an easterly component, such as the easterly trade winds.
murray-darling basin commissionThe executive arm of the Murray-Darling Basin Ministerial Council
phytoplanktonMinute plants, usually algae, that live suspended in bodies of water and that drift about because they are too small or too weak to swim effectively against the current.
hydraulic radiusThe cross-sectional area of a stream divided by the wetted perimeter.
waterfalla sudden, nearly vertical drop in a stream, as it flows over rock.
dense fog advisoryAdvisory issued when fog reduces visibility to 1/8 mile or less, creating possible hazardous conditions.
euphotic zonesurface layer of an ocean, lake, or other body of water through which light can penetrate
tablewater 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).
prtAn acronym for Platinum Resistance Thermometer
food chainA sequence of organisms, each of which uses the next, lower member of the sequence as a food source.
tributaryA river or stream flowing into a larger stream
tropical depressionA tropical cyclone in which the maximum sustained surface winds are 38 miles per hour (33 knots) or less
greenhouse effectThe warming of the earth's atmosphere caused by a build-up of carbon dioxide or other trace gases; it is believed by many scientists that this build-up allows light from the sun's rays to heat the earth but prevents a counterbalancing loss of heat.
absolute zeroConsidered to be the point at which theoretically no molecular activity exists or the temperature at which the volume of a perfect gas vanishes
flow regimeThe spatial and temporal patterns of flow in a river.
nutrientsnitrates and phosphates, usually resulting       in an increase in biomass and productivity, (see oligotrophic).
deltaA delta is a low, watery land formed at the mouth of a river
stratigraphyThe arrangement of strata or geologic layers
hardwood bottomlandhardwood forested lowlands adjacent to some rivers, especially valuable for wildlife breeding, nesting, and habitat.
isobarThe line drawn on a weather map connecting points of equal barometric pressure.
flushto open a cold-water tap to clear out all the water which may have been sitting for a long time in the pipes; to force large amounts of water through a system to clean out piping or tubing and storage or process tanks.
index of biotic integritya multi-metric measure of biological condition developed from collection of data for fish or other organisms
activated carbon adsorptionthe process of pollutants moving out of water and attaching on to activated carbon.
fingerlingsmall fish under one year of age
vadose zonethe zone between land surface and the water table where the moisture content is less than saturation (except in the capillary fringe) and pressure is less than atmospheric
substrateinorganic material that forms the streambed
baroclinityThe state of stratification in a fluid in which surfaces of constant pressure intersect surfaces of constant density
deltaan alluvial deposit made of rock particles (sediment, and debris) dropped by a stream as it enters a body of water.
bed slopeThe inclination of the channel bottom, measured as the elevation drop per unit length of channel.
external costcost of production or consumption that must be borne by society; not by the producer.
conservation recommendationsSuggestions by conservation agencies regarding discretionary measures to minimize or avoid adverse effects on a proposed action of federally listed threatened or endangered species or designated critical habitat.
multicell stormA thunderstorm made up of two or more single-cell storms.
planktonmicroscopic floating plant and animal organisms of lakes, rivers, and oceans.
graded streamGeomorphic term used for streams that have apparently achieved a state of equilibrium between the rate of sediment transport and the rate of sediment supply throughout long reaches.
watershedArea that drains to a common outlet
salinity intrusionThe movement of saltwater into a body of freshwater
planktonmicroscopic plants and animals suspended in the water
pascalThe unit of pressure produced when one newton acts on about one square meter.
river channelsThe trenches in which rivers flow for most of the year.
seed bankGround or soil where multiple seeds from plant species are stored until germination.
anistropic aquiferan aquifer in which permeability varies with direction of flow
snow garlandSnow appearing as a beautiful long thick rope draped on trees, fences and other objects
condensationthe change of state from a gas to a liquid
surface supplyWater supply from streams, lakes, and reservoirs.
littoral zonearea on or near the shore of a body of water.
earthlightThe faint illumination of the dark part of the moon's disk produced by sunlight reflected onto the moon from the earth's surface and atmosphere.
biosphereThe transition zone between the earth and the atmosphere within which most terrestrial life forms are found
permeabilitythe ability of a water bearing material to transmit water
quicksilver watera solution of mercury nitrate used in gilding.
wetted perimeterThe boundary of wetted contact between a stream of flowing water and its containing channel at a given discharge, measured in a direction perpendicular to the flow.
phreatic zonethe area in an aquifer in which relatively all pores and fractures are saturated with water
longitudinal profileA graphic presentation of elevation vs
absolute humidityA type of humidity that considers the mass of water vapor present per unit volume of space
lateral erosionErosion in which the removal of material is extended horizontally as contrasted with degradation and scour in a vertical direction.
erosionThe wearing away, in this case by water and rocks constantly rubbing
cut-off highA warm high which has become displaced and is on the polarward side of the jet stream
tributarya river of creek that flows into a larger river.
nutrient enrichmentA term that describes the addition of too much nutrient (nitrogen, phosphorus and carbon), to waterbodies from human actions and the resulting responses that typically leads to changes in plant and animal communities and degradation of water and sediment quality.
mesoscaleThe scale of meteorological phenomena that range in size from several kilometers to around 100 kilometers
atropisomeris a stereoisomer that results from hindered rotation about a single bond where the steric strain barrier to rotate is high enough to isolate the different conformers.
brackishBeackish water is water that is saltier than river water but less salty than sea water.
frontolysisThe destruction or dying of a front where the transition zone is losing its contrasting properties
haila form of precipitation which forms into balls or lumps of ice over 0.2 inch in diameter
detentionWater management practice or system that delays the downstream progress of stormwater by the use of temporary storage or metered outlets.
hydraulic radiusCorss-sectional area divided by the wetted perimeter.
controllerA device that regulates the power supply to a heater or bath to bring it up to a specified temperature.
organometallicthe compound has at least one metal-carbon bond i.e
unconfined aquiferan aquifer containing water that is not under pressure; the water level in a well is the same as the water table outside the well
mesicModerately wet.
covervegetation or other features that provide shelter for wildlife
organic carbonRefers to carbon that is bound to organic compounds, usually described as the amount of decaying natural organic matter in a water sample.
sanitary sewersunderground pipes that carry off only domestic or industrial waste, not storm water.
ip ratingA measure of an instrument's protection against the ingress of dust, water and other substances into the equipment
recruitmentsurvival of young plants and animals from birth to a life stage less vulnerable to environmental change.
thermodynamicsStudy of the processes that involve the transformation of heat into mechanical work, of mechanical work into heat, or the flow of heat from a hotter body to a colder body.
tributarysmall, permanent stream emptying into the main stem of the river.
glaciera huge mass of land ice that consists of recrystallized snow and moves slowly downslope or outward.
constant pressure surfaceA surface along which the atmospheric pressure is equal everywhere.
marshan area periodically inundated and treeless and often characterized by grasses, cattails, and other monocotyledons
hydrogeologythe geology of groundwater, with particular emphasis on the chemistry and movement of water.
significant ecological assetRelating to the six significant ecological assets: Barmah-Millewa Forest, Gunbower and Koondrook-Perricoota forests, Hattah Lakes, Chowilla Floodplain, Murray Mouth and Corrong and Lower Lakes and the River Murray Channel.
barrierA physical block or impediment to the movement or migration of fish, such as a waterfall (natural barrier) or a dam (man-made barrier).
pool/riffle ratioThe ratio of surface area or length of pools to the surface area or length of riffles in a given stream reach; frequently expressed as the relative percentage of each category
pavementStreambank surface covering, usually impermeable, designed to serve as protection against erosion
national estuary programa program established under the Clean Water Act Amendments of 1987 to conserve and manage estuaries, restore and maintain their chemical, physical, and biological integrity, and control point and nonpoint pollution sources.
prehistoricbefore people were around to keep records of history
infrared spectroscopyis a spectroscopic technique to identify functional groups, looks at vibrational modes of the molecule
landscape impoundmentbody of reclaimed water which is used for aesthetic enjoyment or which otherwise serves a function not intended to include contact recreation.
imperiled speciesdeclining, rare, or uncommon species; species federally listed as threatened or endangered, or candidates for such; and species with limited distributions.
urban runoffStorm water from city streets and gutters that usually carries a great deal of litter and organic and bacterial wastes into the sewer systems and receiving waters.
siltationThe deposition or accumulation of fine soil particles.
channelAn area that contains continuously or periodically flowing water that is confined by banks and a stream bed.
biodiversitybiological diversity or the variety of life forms, comprising genetic diversity (within species), species diversity and ecosystems diversity.
mobile phaseis a term used in chromatography
meanderBend or curve in a stream channel.
coliform bacteriathat 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.
environmental impactthe positive or negative effect of any action upon a given area or source.
flood-frequency curveGraph indicating the probability that the annual flood discharge will exceed a given magnitude, or the recurrence interval corresponding to a given magnitude.
solutechemical 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.
helical flowThree‑dimensional movement of water particles along a spiral path in the general direction of flow
effective porositythe portion of pore space in saturated permeable material where the movement of water takes place.
coromellThe prevailing evening land breeze which takes place from November to May in the vicinity of La Paz, at the southern tip of Baja California, Mexico.
aquiferA body of rock that is sufficiently permeable to conduct groundwater and to yield economically significant quantities of water to wells and springs.
water yieldThe quantity of water derived from a unit area of watershed.
interceptor sewervery large sewer lines that collect the flow from main and trunk lines and carry them to treatment plants.
peninsulaA peninsula is a body of land that is surrounded by water on three sides.
wellfieldarea containing one or more wells that produce usable amounts of water or oil.
nutrient depletionDetrimental changes on a site in the total amount of nutrients and/or their rates of input, uptake, release, movement, transformation, or export.
safe yieldthe annual amount of water that can be taken from a source of supply over a period of years without depleting that source beyond its ability to be replenished naturally in "wet years."
depthHow deep the water is.
grass/forbHerbaceous vegetation.
daily dischargeDischarge averaged over 1 day (24 hours).
community water systemIn Texas, a public water system which has a potential to serve at least 15 residential service connections on a year-round basis or serves at least 25 residents on a year-round basis.
predatoran animal that hunts and kills other animals for food
tropical stormA tropical cyclone in which the maximum sustained surface winds are from 39 miles per hour (34 knots) to 73 miles per hour (63 knots)
bankThe ground at the side of a river
reservesamount of a particular resource in known locations that can be extracted at a profit with present technology and prices.
big waterTo avoid reducing channel capacity, the San Antonio River Improvements Project plan calls for these wider stretches of water to be excavated just upstream of a grade control structure where the overall main channel can be widened
geohydrologya term which denotes the branch of hydrology relating to subsurface or subterranean waters; that is, to all waters below the surface.
bed loadSediment that moves near the streambed.
cfucolony forming units.  Concentrations of water quality indicator organisms such as fecal coliform bacteria are measured in cfu/100 ml.
kilowatt hourOne kilowatt of power applied for one hour.
stream powerMeasure of energy available to move sediment, or any other particle in a stream channel
coliformA group of bacteria found in the intestines of warm-blooded animals (including humans), also in plants, soil, air, and water
turbidthick or opaque with matter in suspension
sand filtersdevices that remove suspended solids from a wastewater treatment plant effluent or water treatment plant product.
channela natural or artificial watercourse that continuously or intermittently contains water, with definite bed and banks that confine all but overbanking streamflows.
jet streakA region of accelerated wind speed along the axis of a jet stream.
meanderthe twisting and turning of a river's flow
dissolved oxygenoxygen dissolved in water; the amount depends on water temperature, plant photosynthesis, plant and animal respiration, and physical aeration
regulateda river or creek where water is released from storage to meet diversions requirements downstream, or to reduce flooding.
meander or full meanderMeander in a river consists of two consecutive loops, one flowing clockwise and the other counter‑clockwise.
recreational riversRivers or sections of rivers that are readily accessible by road or railroad, that may have some development along their shoreline, and that may have undergone some impoundment or diversion in the past.
upstreamOpposite to the currents flow - towards the source of the river
cyclogenesisThe process that creates a new low pressure system or cyclone, or intensifies a pre-existing one
channel forming flowSee Dominant Discharge
flashinessa measure of a river or stream's tendency to carry a high percentage of its flow volume in large, infrequent events rather than more moderate flows that occur frequently.
water cyclethe process of water moving from a lake or ocean to the clouds and back to the earth again
hydraulic roughnessan estimate of the resistance to flow due to energy loss caused by friction between the channel and the water
reachA section of stream between two defined points.
impairmentImpact that damages the biological integrity of a water body such that attainment of the designated use is prevented.
sedimentationDeposition of sediment.
riparianRelated to the banks or floodplain area of a natural watercourse.
environmental flowsflows, or characteristics of the flow pattern, that are either protected or created to benefit the natural environment.
pollutionThe alteration of the physical, chemical, or biological properties of water by the introduction of any substance into water that adversely affects any beneficial use of water.
gaging stationA particular point on a stream of known cross-section where systematic observations of water depth or discharge are obtained.
kcfsA measurement of water flow equivalent to 1,000 cubic feet of water passing a given point for an entire second.
long wave troughA wave in the prevailing westerly flow aloft which is characterized by a large length and amplitude
buoyancythe tendency of a body to float or rise when immersed in a fluid; the power of a fluid to exert an upward force on a body placed in it.
commence to flowVolume at which flow spills into a channel or wetland
validationcomparison of computer model results with a set of data that were not used for calibration.
eddyA circular current or a current of water running contrary to the main current, usually resulting from an obstruction.
blowing spraySalt spray that is raised by the wind to heights of six feet or greater
natural flowthe rate of water movement past a specified point on a natural stream
epiphyteA non-parasitic plant that grows upon another plant.
bed materialThe sediment mixture of which a streambed, lake, pond, reservoir, or estuary bottom is composed.
ripple(1) A specific undulated bed form found in sand bed streams
odonatesInsect groups such as dragonflies and damselflies.
check damA structure placed bank-to-bank downhill from a headcut on a hillslope to help revegetate a gully.
data loggerAn electronic device that records temperature data at a specific location at regular intervals over time with either a built-in sensor or through external sensors or probes
indicator teststests for a specific contaminant, group of contaminants, or constituent which signals the presence of something else (ex., coliforms indicate the presence of pathogenic bacteria).
ansiAn acronym for American National Standards Institute
textureRefers to relative proportions of clay, silt, and sand in soil.
capillary actionmovement of water through very small spaces due to molecular forces called capillary forces.
mouthThe end of the river
staphylococcusA microscopic bacteria common to skin and mucous membranes
climate changeThe slow variations of climatic characteristics over time at a given place.
supplya schedule that shows the various quantities of things offered for sale at various prices at a point in time
derechoA line of intense, widespread, and fast-moving thunderstorms that moves across a great distance
intersticesthe void or empty portion of rock or soil occupied by air or water.
teleconnectionsInformation used by forecasters to determine what the weather might be elsewhere when compared with past weather conditions at the same degree of longitude.
biogeochemical cyclingthe flow of chemical substances to and from the major environmental reservoirs (atmosphere, hydrosphere, lithosphere, and biosphere).
parts per millionThe number of "parts" by weight of a substance per million parts of water
reclaimed waterdomestic wastewater that is under the direct control of a treatment plant owner/operator which has been treated to a quality suitable for a beneficial use.
heat of vaporizationthe amount of heat necessary to convert a liquid (water) into vapor.
indicator parametersmeasurable physical or chemical characteristics or attributes of water or soil-pore moisture used to indicate the possible presence of waste constituents, or the effects of waste constituents on waters.
assimilationthe ability of a water body to purify itself of pollutants.
longitudeLongitude is the angular distance east or west from the north-south line that passes through Greenwich, England, to a particular location
communityAll the living organisms present in an ecosystem
infiltrationThe downward movement of water through soil or porous rock.
droughtA continuous and lengthy period during which no significant precipitation is recorded.
impervious surfaceSurfaces, such as roads, parking lots and roofs, whose properties prevent the infiltration of water and increase the amount of stormwater runoff in a watershed.
point sourceSource of pollution from a single, well-defined outlet
stockingrelease of fish into the wild
gallons per minuteA unit used to measure water flow.
springA place where water naturally seeps or gushes from the ground - often in marsh or bog areas
coniferouscone-bearing trees with needles
geomorphologyThe branch of geology that studies the nature and origin of land forms
phAn expression of both acidity and alkalinity on a scale of 0 to 14, with 7 representing neutrality; numbers less than 7 indicate increasing acidity and numbers greater than 7 indicate increasing alkalinity.
waterfallA waterfall is a sudden drop in a river as it flows over a rock cliff
plug flowtype of flow that occurs in tanks, basins, or reactors when a slug of water moves through without ever dispersing or mixing with the rest of the water flowing through.
habitatthe native environment or specific surroundings where a plant or animal naturally grows or lives
drawdownThe process of lowering the water level in a reservoir
pluvialOf rain, formed by the action of rain, for example a body of water.
clay plugCutoff meander bend filled with fine grained cohesive sediments.
water cycleevapotranspiration, 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
anaerobic sedimentsAquatic sediments that have a high organic matter content
mid-channel barBar lacking permanent vegetal cover that divides the flow in a channel at normal stage.
subsurface drainageRainfall that is not evapotranspirated or does not become surface runoff.
native vegetationVegetation indigenous to an area and adapted to local conditions.
transpirationthe 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).
deadmanA log, block of concrete, rebar, or other object buried in a stream bank that is used to tie in revetment with cable or chain.
saltwater barrierA physical facility or method of operation designed to prevent the intrusion of saltwater into a body of freshwater.
precisionSee resolution.
extinctioncomplete disappearance of a species because of failure to adapt to environmental change.
evaporationconversion of water from liquid to vapour
hazardous materialsAnything that poses a substantive present or potential hazard to human health or the environment when improperly treated, stored, transported, disposed of, or otherwise managed.
artesian zonea zone where water is confined in an aquifer under pressure so that the water will rise in the well casing or drilled hole above the bottom of the confining layer overlying the aquifer.
climateMeteorological elements that characterize the average and extreme conditions of the atmosphere over a long period of time at any one place or region of the earth's surface.
banksBanks are the sides of a river or stream between which the water normally flows.
supply augmentationAlternative water management programs such as conjunctive use, water banking, or water project facility expansion that increase supply.
triturationcommonly refers to the grinding of powders in a pestle or mortar
ephemeral streamA water course that is usually dry but sporadically contains stream flow, typically during significant rain or snowmelt events.
reachRefers to a section of a main channel, usually defined between channel bends.
knickpointThe point on a stream's profile where a sudden change in stream gradient occurs.
adaptive managementAdaptive management is a systematic process for continually improving management policies and practices by learning from the outcomes of operational programs by employing management programs that are designed to experimentally compare selected policies or practices, by evaluating alternative hypotheses about the system being managed.
polychlorinated biphenylstoxic industrial chemical compound substances that were used in the manufacture of plastics and as insulating fluids in electrical transformers and capacitors
scourthe erosive action of running water in streams, which excavates and carries away material from the bed and banks
plugcement, grout, or other material used to fill and seal a hole drilled for a water well.
imperviousAllowing little or no water to infiltrate; water tight
tornado alleyA geographic corridor in the United States which stretches north from Texas to Nebraska and Iowa
water-soluble substancea substance that can readily disperse through the environment.
fresh:salt water interfacethe region where fresh water and salt water meet
ecoregiona geographic area over which the macroclimate is sufficiently uniform to permit development of similar ecosystems on sites with similar geophysical properties.
holoceneGeological time spanning the last 10 000 years.
calmAtmospheric conditions devoid of wind or any other air motion
sedimentationThe physical process of settling of suspended particulates under the force of gravity (ARMCANZ & ANZECC 2000).
chocolatta northA West Indian gale that blows from the northwest.
pathogenmicroorganisms which can cause disease.
hydrologyThe study of the waters of the earth, especially with relation to the effects of precipitation and evaporation upon the occurrence and character of water in streams, lakes, and on or below the land surface.
confluenceA rate at which wind flow comes together along an axis oriented normal to the flow in question
riverA large stream of water that flows along a certain path.
greenbeltStrip of natural vegetation growing parallel to a stream that provides wildlife habitat and an erosion and flood buffer zone
dischargeThe rate at which a volume of water passes through a cross section in a unit of time.
crownthe upper part of a tree or other woody plant that carries the main system of branches and the foliage.
tractive forceThe drag on a streambed or bank caused by passing water, which tends to pull soil particles along with the streamflow.
skimmingusing a machine to remove oil or scum from the surface of the water.
salt marshSaltwater wetlands that occur along many coasts.
secondary treatmentIn sewage, the biological process of reducing suspended, colloidal, and dissolved organic matter in effluent from primary treatment systems
water-resistantA non-technical term used to describe instruments that are protected from the ingress of liquids
operating guidelinesA set of guidelines that includes flood guides, minimum flow requirements, water release requirements, and other requirements to meet system operating objectives.
floodan overflow or inundation that comes from a river or other body of water and causes or threatens damage
infiltrationthe penetration of water through the ground surface into sub-surface soil or the penetration of water from the soil into sewer or other pipes through defective joints, connections, or manhole walls.
cfsCubic feet per second, typically used as a measure of flow in a stream
perigeeThe point nearest the earth on the moon's orbit
siberian highThe semi-permanent high pressure area that forms over Siberia during the winter
segmenta water body or portion of a water body that is individually defined and classified
circulateto move in a circle, circuit or orbit; to flow without obstruction; to follow a course that returns to the starting point.
hysteresisA quality of a system such that the output is not only determined by the input but also by the internal state of the system, particularly as it is affected by previous measurements
thermal lowAlso known as heat low, it is an area of low pressure due to the high temperatures caused by intensive heating at the surface
tertiary treatmentremoval from wastewater of traces or organic chemicals and dissolved solids that remain after primary treatment and secondary treatment.
toxicanta substance or a mixture of substances within a short period of time,         usually 96 hours or less, after exposure
forebaythe water behind a dam.
rill erosionRemoval of soil particles from a bank slope by surface runoff moving through relatively small channels
salinisationthe accumulation of salts in the soil to a level that causes degradation of the soil.
hydrologic cycleThe hydrologic cycle is another name for the water cycle.
meander amplitudeThe distance between points of maximum curvature of successive meanders of opposite phase in a direction normal to the general course of the meander belt, measured between centerlines of channels.
consumersorganisms that depend on other organisms for their food
boiling pointis the temperature when a liquid becomes a gas
fissileGeologic term referring to rock (generally shale) that breaks along parallel planes as it weathers, resulting in thin, plate-like fragments.
gaseousin a gas-like state; not solid, not liquid - like steam
squallA sudden onset of strong winds with speeds increasing to at least 16 knots (18 miles per hour) and sustained at 22 or more knots (25 miles per hour) for at least one minute
macrophytesAquatic plants that are large enough to be seen with the naked eye.
hydrologic regionA study area, consisting of one or more planning subareas, that has a common hydrologic character.
dischargeThe amount of water flowing in a river per second.
osmosisthe passage of a liquid from a weak solution to a more concentrated solution across a semi-permeable membrane that allows passage of the solvent (water) but not the dissolved solids.
hydrologythe science dealing with the properties, distribution, and circulation of water.
multi-disciplinary approachAn approach that utilizes the skills, knowledge and experience of professionals from several fields to develop a more holistic understanding and treatment of the components, issues, problems and variables of a project.
polychlorinated biphenylsA group of chemicals found in industrial wastes.
residuethe dry solids remaining after the evaporation of a sample of water or sludge.
blowing sandSand that is raised by the wind to heights of six feet or greater
high flow pulsesthe component of an instream flow regime that represents short-duration, in-channel, high flow events following storm events
rockSee cobble.
mountain breezeA katabatic wind, it is formed at night by the radiational cooling along mountainsides
backwater poolA pool that formed as a result of an obstruction like a large tree, weir, dam, or boulder.
pumpa device which moves, compresses, or alters the pressure of a fluid, such as water or air, being conveyed through a natural or artificial channel.
blowing snowSnow that is raised by the wind to heights of six feet or greater
chemosphereA vaguely defined region of the upper atmosphere in which photochemical reactions take place
tailwaterThe part of a river downstream from a dam, where the flow and quality of the water are substantially affected by the dam discharge.
water yearA continuous 12-month period for which hydrologic records are compiled and summarized.