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Acequias are gravity-driven waterways, similar in concept to a flume. Most are simple ditches with dirt banks, but they can be lined with concrete. They were important forms of irrigation in the development of agriculture in the American Southwest. The proliferation of cotton, pecans and green chile as major agricultural staples owe their progress to the acequia system.

A substance that has a pH of less than 7, which is neutral. Specifically, an acid has more free hydrogen ions (H+) than hydroxyl ions (OH-).

Acid Rain
Acid Rain is rain that has been made acidic by certain pollutants released in the air, most commonly caused by human activities. Acid rain creates tiny particles which can easily enter people's lungs and cause health problems, especially those with difficulty breathing. Acid rain also harms forests by precipitating harmful toxins into the soil which then destroys certain nutrients that nature is dependent on. Lastly, acid rain damages lakes and streams by increasing the acidity in water which can be deadly to aquatic wildlife.

Acre-foot (acre-ft)
The volume of water required to cover 1 acre of land (43,560 square feet) to a depth of 1 foot. Equal to 325,851 gallons or 1,233 cubic meters.

Albumin is the main protein in human blood and is the key to the regulation of the osmotic pressure of blood. Albumin is important because it has the ability to bind to water and without it our tissues would swell up with water.

Sometimes water or soils contain an amount of alkali (strongly basic) substances sufficient to raise the pH value above 7.0 and be harmful to the growth of crops.

The capacity of water for neutralizing an acid solution.

Deposits of clay, silt, sand, gravel, or other particulate material that has been deposited by a stream or other body of running water in a streambed, on a flood plain, on a delta, or at the base of a mountain.

An abundant metallic chemical widely used throughout the world for a wide range of products. Aluminum is a malleable metal commonly used to make soda cans. It is the third most common element in the Earth's crust and is the most common metallic element on Earth. Aluminum in drinking water is said to be associated with Alzheimer's disease because the aluminum could damage nerve cells and their connectors.

A colorless gas with a pungent odor used commonly in commercial cleaning products. Most people are exposed to ammonia from inhalation of the gas or vapors. Ammonia interacts immediately with the moisture in the skin, eyes, respiratory tract, and causes the necrosis of tissues through disruption of cell membrane lipids leading to cellular destruction.

A decrease in the number of red blood cells or less than the normal quantity of hemoglobin in the blood. Hemoglobin normally carries oxygen to the tissues so anemia leads to lack of oxygen in organs.

A medication used to control or prevent seizures. The goal of the anti-convulsant is to suppress the rapid and excessive firing of neurons that start a seizure.

Any remedy that cures or prevents scurvy. Foods with high concentrations of Vitamin C have excellent sources of anti-scorbutic.

A medicine used to treat infections by killing the bacteria and inhibiting its ability to reproduce. Antibiotics do not work on viruses because viruses are not alive, unlike bacteria. It is important to finish the course of the prescribed antibiotics so the bacteria is fully killed. If some bacteria remain, they can reproduce causing the illness to come back which also means they will be stronger the next time you take the antibiotic.

Appropriation doctrine
The system for allocating water to private individuals used in most Western states. The doctrine of Prior Appropriation was in common use throughout the arid west as early settlers and miners began to develop the land. The prior appropriation doctrine is based on the concept of "First in Time, First in Right." The first person to take a quantity of water and put it to Beneficial Use has a higher priority of right than a subsequent user. Under drought conditions, higher priority users are satisfied before junior users receive water. Appropriative rights can be lost through nonuse; they can also be sold or transferred apart from the land. Contrasts with Riparian Water Rights.

A disease of the bone joint which refers to an area where two bones are fixed for the purpose of allowing movement of body parts. It is associated with a disparity between the production and deterioration of bone cells. As the disease gets worse it can result in the loss of free movement in the joint.

Farming of plants and animals that live in water, such as fish, shellfish, and algae.

A pipe, conduit, or channel designed to transport water from a remote source, usually by gravity.

A geologic formation(s) that is water bearing. A geological formation or structure that stores and/or transmits water, such as to wells and springs. Use of the term is usually restricted to those water-bearing formations capable of yielding water in sufficient quantity to constitute a usable supply for people's uses.

Aquifer (confined)
Soil or rock below the land surface that is saturated with water. There are layers of impermeable material both above and below it and it is under pressure so that when the aquifer is penetrated by a well, the water will rise above the top of the aquifer.

Aquifer (unconfined)
An aquifer whose upper water surface (water table) is at atmospheric pressure, and thus is able to rise and fall.

A odorless and tasteless chemical element commonly used to strengthen alloys of copper and especially lead. Arsenic poisoning can occur when arsenic is consumed in high concentrations in drinking water. The EPA has set the standard for drinking water at 0.010 parts per million to protect consumers from the long term, chronic effects of arsenic. Arsenic has been linked to cancer of the bladder, lungs, skin, kidney, liver and more.

Artesian Water
Ground water that is under pressure when tapped by a well and is able to rise above the level at which it is first encountered. It may or may not flow out at ground level. The pressure in such an aquifer commonly is called artesian pressure, and the formation containing artesian water is an artesian aquifer or confined aquifer.

Artificial Recharge
An process where water is put back into ground-water storage from surface-water supplies such as irrigation, or induced infiltration from streams or wells.

A set of six naturally occurring silicate minerals used commercially for their desirable physical properties. Asbestos is useful because of its sound absorption, strength, and its resistance to heat and electrical damage. Exposure to asbestos fibers increase your risk of developing lung disease. Asbestos used to be used in homes as fire proofing, roofing, and flooring but most products made today do not contain asbestos.

Asthma is the inflammation and swelling of the airways which is a chronic condition that affects the ability to breathe. Symptoms of asthma include shortness of breathe, wheezing, coughing, and tightness in the chest. It is important to manage your asthma everyday because several factors can trigger it and make symptoms worse such as allergies, infections, or strong odor or fumes.

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A single cell microorganism which can exist either as an independent organism or upon another organism for life. Bacteria can cause disease, spoil food, and contaminate water. The transmission of disease through drinking water can occur when drinking water has been contaminated by human or animal waste.

A substance that has a pH of more than 7, which is neutral. A base has less free hydrogen ions (H+) than hydroxyl ions (OH-).

Base flow
Sustained flow of a stream in the absence of direct runoff. It includes natural and human-induced streamflows. Natural base flow is sustained largely by ground-water discharges.

The solid rock beneath the soil and superficial rock. A general term for solid rock that lies beneath soil, loose sediments, or other unconsolidated material.

Any remedy that cures or prevents scurvy. Lemons for example, are rich in Vitamin C and act as an anti-scorbutic to aid in the cure of scurvy.

To cause to swell or inflate with liquid, gas, or air. Most commonly caused by fluid retention (water retention), or sometimes irritable bowel syndrome and stress.

Biochemical Oxygen Demand (BOD)
The amount of dissolved oxygen needed by aerobic biological organisms in a body of water to break down organic material present in a given water sample at certain temperature over a specific time period. BOD can be used to gauge the effectiveness of wastewater treatment plants.

Body Hydration
Water is the largest component of your body so it is vital to keep your body hydrated. Most doctors recommend drinking 8 to 9 cups of water per day to maintain proper body hydration, however it can vary depending on how much one exercises or how much one weighs. A sign of thirst is the first sign of dehydration.

Inflammation of the main air passages to the lungs. Bronchitis can be divided into two types, acute and chronic. Acute is most commonly developed by a cough during the course of a viral illness. Chronic most often develops from a recurrent injury to the airways by inhaled irritants, such as smoking.

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A minor metallic element naturally occurring in the earth's crust and waters. Cadmium used to be used as a pigment for corrosion resistant plating on steel while cadmium compounds were used to stabilize plastic. Now cadmium is used less and less due to competing technologies. Exposure to certain forms and concentrations of cadmium is known to produce toxic effect on humans.

The most abundant mineral in the human body stored mostly in our bones and teeth. The body constantly breaks down and rebuilds the bones, however the older the body gets it tends to reabsorb more calcium than it returns leading to osteoporosis. Calcium is found in milk, cheese, yogurt, dark green vegetables, but more importantly your body needs Vitamin D to be able to absorb the calcium.

Capillary action
The means by which liquid moves through the porous spaces in a solid, such as soil, plant roots, and the capillary blood vessels in our bodies due to the forces of adhesion, cohesion, and surface tension. Capillary action is essential in carrying substances and nutrients from one place to another in plants and animals.

Any substance that is an agent directly involved in causing cancer. This may be due to the damage or disruption of cellular metabolic processes. Carcinogens may increase the risk of cancer by altering cellular metabolism or damaging DNA directly in cells.

Chemicals that are a compound or substance that is used or results from a reaction involving changes to atoms or molecules. Chemicals exist as solids, liquids, gases, or plasma and may change between these phases of matter with changes in temperature or pressure. Drinking water is often contaminated with toxic chemicals and need to be filtered or it can cause severe illness over time.

A yellow-green gas with a pungent, irritating odor similar to bleach. Chlorine can be pressurized and cooled to change into a liquid form. Chlorine is used to disinfect pools, used as bleach in the manufacture of paper and cloth, and used to make pesticides and solvents. Chlorine is used in drinking water to kill harmful bacteria but overtime the continuous consumption of low levels of chlorine can cause serious health problems.

Chlorophyll gives leaves their green color and absorbs light that is used in photosynthesis. Chlorophyll makes it possible for plants to convert carbon dioxide and water into oxygen and glucose in the presence of sunlight. Chlorophyll produces energy which gives power to the plants essential growth and development.

A condition in which small calculi form in the gall bladder, also known as gallstones. There are two types of gallstones, one type is made up of cholesterol and the other is made up of bilirubin, which can occur when red blood cells are being destroyed. Symptoms most often includes pain in the upper or middle abdomen, fever, jaundice, and vomiting.

Chronic Dehydration
The body is comprised of 75% water and is required for many essential functions of the body. Over time when the body is not properly hydrated chronic dehydration occurs which can lead to fatigue, constipation, high/low blood pressure, stomach ulcers, repertory problems, and many more.

A steel-like gray, odorless, tasteless, hard metal that takes a high polish and has a high melting point. Chromium is known for its high corrosion resistance, hardness, and remarkable magnetic properties. Chromium compounds bind to soil and eventually contaminate drinking water. Health effects include skin irritation, ulceration, and liver and kidney damage.

Clean Water Act
This act gives the EPA the authority to set limits on water quality basis that ensure protection of the receiving water. This will help to regulate the discharge of pollutants from point sources to waters in the United States.

Coliform Bacteria
Coliform is a type of bacteria that is present in the environment and in the feces of all warm blooded animals and humans. Coliforms themselves do not cause serious illness but are rather used as an indicator of sanitary quality of foods and water. If coliform bacteria is found in your drinking water your water system it should be inspected to find and eliminate any other sources of contamination.

Commercial water use
Water used for motels, hotels, restaurants, office buildings, other commercial facilities, and institutions. Water for commercial uses comes both from public-supplied sources, such as a county water department, and self-supplied sources, such as local wells.

The process of water vapor in the air turning into liquid water. Water drops on the outside of a cold glass of water are condensed water. Condensation is the opposite process of evaporation.

Connate Water
Refers to liquids that have been trapped in the pores of sedimentary rocks as they were deposited. These liquid solutions are composed of water and contain many mineral components. As rocks are buried it may block the escape route which can cause a pore fluid pressure to build up, leading to overpressure.

Consumptive use
That part of water withdrawn that is evaporated, transpired by plants, incorporated into products or crops, consumed by humans or livestock, or otherwise removed from the immediate water environment. Also referred to as water consumed.

Conveyance loss
Water that is lost in transit from a pipe, canal, or ditch by leakage or evaporation. Generally, the water is not available for further use; however, leakage from an irrigation ditch, for example, may percolate to a ground-water source and be available for further use.

A malleable metallic element used in large quantities as an electrical conductor such as brass and bronze. Copper is often found in drinking water because of the corrosion of water pipes and can cause short and long term illness.

When a material deteriorates due to interaction with the environment. Dissimilar metal, oxygen, water, and debris can all cause corrosion. For example, when the pH of water is lower than 8, copper oxide no longer creates a barrier in the pipe and causes the pipe to corrode. This can be harmful to health because corroded particles may enter the drinking water supply.

Cubic feet per second (cfs)
A rate of the flow, in streams and rivers, for example. 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 flowing each second. As an example, if your car's gas tank is 2 feet by 1 foot by 1 foot (2 cubic feet), then gas flowing at a rate of 1 cubic foot/second would fill the tank in two seconds.

Widespread intestinal parasite that causes diarrheal illness in people. Cysts are extremely small; they are about ten times smaller than the smallest object that can be seen with the naked eye. When cysts are consumed they hatch in the small intestine and multiply causing diarrhea, nausea, abdominal cramps, and weight loss. Cysts are most commonly transmitted by untreated drinking water.

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Dehydration occurs when the body is lacking in vital fluids. The first sign of dehydration is typically a headache followed by dizziness and severe thirst. More severe dehydration symptoms involve loss of appetite, muscle cramping, and increased heart rates. When the body loses more than 15% of its water volume, it is usually fatal.

The process used to remove all salts from water. The first step removes the calcium and magnesium ions, and in the process replaces them with hydrogen ions instead of sodium. The second step is an anion exchange where the negative ions (anions) are absorbed into the anion exchange and release hydroxyl anions. The result of this two step ion exchange is mineral free water.

The removal of salts from saline water to provide freshwater. This method is becoming a more popular way of providing freshwater to populations.

Short for detoxification, is the physiological or medicinal removal of toxic substances from a living organism. A diet detox serves as a plan to eliminate waste or toxic materials out of the body, leaving a toxin-free healthy body. There are different types of detox diets for alcohol addiction, improved digestion, enhanced concentration, drug detoxification and many more.

A highly contagious bacterial disease causing inflammation of the mucous membrane. It is an upper respiratory tract illness caused by the bacteria "Corynebacterium diphtheriae" which most commonly affects the nose and the throat. Diphtheria is a disease spread by direct physical contact, however it is rare to develop these days because of immunization.

The volume of water that passes a given location within a given period of time. Usually expressed in cubic feet per second.

Distilled Water
Water that has many of its impurities removed through distillation. Distillation is the process of boiling water which condensates the clean water into a container leaving a broad range of contaminants behind. Distillation's disadvantage is that it requires a large amount of energy and water which can be costly.

Substance that is natural or synthetic which promotes the excretion or release of urine. Caffeine, cranberry juice, and green tea are examples of diuretics. Diuretic medication can be very effective in treating many conditions such as hypertension, varicose veins and premenstrual syndrome. Diuretics can cause the body to lose too much fluid and result in dehydration.

Domestic water use
Water used for household purposes, such as drinking, food preparation, bathing, washing clothes, dishes, and dogs, flushing toilets, and watering lawns and gardens. About 85% of domestic water is delivered to homes by a public-supply facility, such as a county water department. About 15% of the Nation's population supply their own water, mainly from wells.

Having physical functions suspended or slowed down for a period of time. Causing no symptoms but not cured and liable to recur.

Drainage basin
Land area where precipitation runs off into streams, rivers, lakes, and reservoirs. It is a land feature that can be identified by tracing a line along the highest elevations between two areas on a map, often a ridge. Large drainage basins, like the area that drains into the Mississippi River contain thousands of smaller drainage basins. Also called a "watershed."

Drip irrigation
A common irrigation method where pipes or tubes filled with water slowly drip onto crops. Drip irrigation is a low-pressure method of irrigation and less water is lost to evaporation than high-pressure spray irrigation.

A lowering of the ground-water surface caused by pumping.

An extended period of time when a region has a deficiency in water supply. This generally occurs in regions that receive below average precipitation and can range from months to even years. Intense drought can cause serious problems to the agriculture and ecosystem.

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Water that flows from a sewage treatment plant after it has been treated.

An ion that is electronically charged and moves to either a negative or positive electrode. Electrolytes are important because they are what your cells use to carry electrical impulses across themselves to other cells. Electrolytes are often added to sports drinks to replenish an athlete with the electrolytes they lost during their workout.

An element consists of only one kind of atom and cannot be broken down into a simpler type of matter.

Endocrine Disrupter
Chemicals that interfere with the process controlled by the endocrine system. These chemicals can be ingested, inhaled, or through touch. Endocrine disruptors can imitate the hormone and disrupt the process of a hormone binding to its receptor which can send incorrect signals to the glands.

Environmental Protection Agency
An agency of the federal government formed to protect human health and the environment by enforcing certain regulations. An example of a regulation that has been passed is the Safe Water Drinking Act. This act requires many actions to protect drinking water and its sources: rivers, lakes, reservoirs, springs, and ground water wells.

The top most layer in a thermally stratified lake. It is warmer and typically has a higher pH but lower dissolved oxygen concentration than the hypolimnion.

A state of rest or balance due to the equal action of opposing forces. Drinking more water can bring the body's functions back to equilibrium and help your body rid problems of water retention.

The process in which a material is worn away by a stream of liquid (water) or air, often due to the presence of abrasive particles in the stream.

A place where fresh and salt water mix, such as a bay, salt marsh, or where a river enters an ocean.

Refers to an increase of nutrients in a body of water. A natural process for the environment, however at an accelerated rate it can become a problem by impacting water quality and biodiversity. As an excess of nutrients are carried into the water an explosion of plant life causes a scarcity of oxygen in the water.

The process of liquid water becoming water vapor, including vaporization from water surfaces, land surfaces, and snow fields, but not from leaf surfaces. See transpiration

The sum of evaporation and transpiration.

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Feed Water
Water that has been purified to prevent scale deposit or corrosion and is supplied to a generator to be converted into steam.

An overflow of water onto lands that are used or usable by man and not normally covered by water. Floods have two essential characteristics: The inundation of land is temporary; and the land is adjacent to and inundated by overflow from a river, stream, lake, or ocean.

Flood, 100-year
A 100-year flood does not refer to a flood that occurs once every 100 years, but to a flood level with a 1 percent chance of being equaled or exceeded in any given year.

Flood plain
A strip of relatively flat and normally dry land alongside a stream, river, or lake that is covered by water during a flood.

Flood stage
The elevation at which overflow of the natural banks of a stream or body of water begins in the reach or area in which the elevation is measured.

Flowing well/spring
A well or spring that taps ground water under pressure so that water rises without pumping. If the water rises above the surface, it is known as a flowing well.

Fluoride is naturally present in many drinking water sources and is said to prevent levels of tooth decay. However, the controversy over fluoride in water supply states that long time exposure has been demonstrated to have effects on skeletal and bone tissues. This is why it is important to get your water levels tested to see the amount of fluoride and other contaminants present in the water.

Freshwater, freshwater
Water that contains less than 1,000 milligrams per liter (mg/L) of dissolved solids; generally, more than 500 mg/L of dissolved solids is undesirable for drinking and many industrial uses.

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Gage height
The height of the water surface above the gage datum (zero point). Gage height is often used interchangeably with the more general term, stage, although gage height is more appropriate when used with a gage reading.

Gaging station
A site on a stream, lake, reservoir or other body of water where observations and hydrologic data are obtained. The U.S. Geological Survey measures stream discharge at gaging stations.

A disinfectant agent as heat, radiation, or a chemical that destroys microorganisms that might carry disease. An ultraviolet light can be installed in a drinking water system to disinfect bacteria, viruses, and other pathogens in the water preventing their ability to multiply.

A geothermal feature of the Earth where there is an opening in the surface that contains superheated water that periodically erupts in a shower of water and steam.

A disease that results from an infection by the protozoan parasite Giardia Intestinalis, caused by drinking water that is either not filtered or not chlorinated. The disorder is more prevalent in children than in adults and is characterized by abdominal discomfort, nausea, and alternating constipation and diarrhea.

A huge mass of ice, formed on land by the compaction and recrystallization of snow, that moves very slowly downslope or outward due to its own weight.

The main form of carbohydrates stored in the liver and muscles, used as fuel during exercise. Glycogen can be stored as energy unlike water, where the body expects us to provide a continuous supply.

Gout is characterized by painful inflammation of the joints, most commonly in the hands and feet. The cause of gout is usually the accumulation of urate crystals around your joint which causes it to become inflamed. Gout is caused by too much uric acid in the blood which can be caused by too much alcohol, meat, being overweight, or other factors.

Wastewater from clothes washing machines, showers, bathtubs, hand washing, lavatories and sinks.

Ground water
(1)Water that flows or seeps downward and saturates soil or rock, supplying springs and wells. The upper surface of the saturate zone is called the water table. (2) Water stored underground in rock crevices and in the pores of geologic materials that make up the Earth's crust.

Ground water, confined
Ground water under pressure significantly greater than atmospheric, with its upper limit the bottom of a bed with hydraulic conductivity distinctly lower than that of the material in which the confined water occurs.

Ground-water recharge
Inflow of water to a ground-water reservoir from the surface. Infiltration of precipitation and its movement to the water table is one form of natural recharge. Also, the volume of water added by this process.

Ground water, unconfined
Water in an aquifer that has a water table that is exposed to the atmosphere.

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More commonly known as rock salt, is a mineral form of Sodium Chloride. Halite occurs when lakes and seas dry up and evaporate, leaving sedimentary minerals behind. Halite is often used to manage ice.

A water-quality indication of the concentration of alkaline salts in water, mainly calcium and magnesium. If the water you use is "hard" then more soap, detergent or shampoo is necessary to raise a lather.

(1)The source and upper reaches of a stream; also the upper reaches of a reservoir. (2) the water upstream from a structure or point on a stream. (3) the small streams that come together to form a river. Also may be thought of as any and all parts of a river basin except the mainstream river and main tributaries.

Hemolytic Uremic Syndrome
A condition that occurs from the abnormal premature destruction of red blood cells. Most cases of HUS occur in children after several days of bloody diarrhea because the damaged red blood cells begin to clog the filtering system in the kidneys which may lead to serious kidney failure. Most cases of HUS are caused by E. coli, which is a foodborne illness.

Used to control all types of weeds in industrial areas. Herbicides are used to kill or control the growth of undesirable plants by affecting their hormones.

Hydraulic Pressure
The force per unit area exerted by a fluid on the surface within the container.

Hydrochloric Acid
Hydrochloric acid is a colorless and odorless solution made up of hydrogen chloride and water. It is also known as gastric acid and found in diluted amounts in our stomachs. Today the acid is used in many functions such as the manufacture of leather goods, pharmaceutical products, and various household cleaning products. In large concentrations HCL releases acid mist in the air which can harm the skin and mucous membranes.

Hydroelectric power water use
The use of water in the generation of electricity at plants where the turbine generators are driven by falling water.

Hydrologic cycle
The cyclic transfer of water vapor 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.

The dense bottom layer of a lake in a thermally stratified lake that lies below the thermocline. Typically the hypolimnion is the coldest layer of a lake in summer and the warmest layer during winter.

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Impermeable layer
A layer of solid material, such as rock or clay, which does not allow water to pass through.

Industrial water use
water used for industrial purposes in such industries as steel, chemical, paper, and petroleum refining. Nationally, water for industrial uses comes mainly (80%) from self-supplied sources, such as a local wells or withdrawal points in a river, but some water comes from public-supplied sources, such as the county/city water department.

Flow of water from the land surface into the subsurface.

An acute viral infection characterized by the inflammation of the respiratory tract. Influenza is contagious and its symptoms are fever, chills, prostration and muscular pain.

Injection well
Refers to a well constructed for the purpose of injecting treated wastewater directly into the ground. Wastewater is generally forced (pumped) into the well for dispersal or storage into a designated aquifer. Injection wells are generally drilled into aquifers that don't deliver drinking water, unused aquifers, or below freshwater levels.

Iron is one of the most abundant metals on earth, and is an essential mineral to the human body health. Iron's main function is to carry oxygen from our lungs throughout our body. Iron deficiency in our body can cause many health issues and is the leading cause of anemia. Iron is also used as a common metal to build automobiles, machine tools, large ships and many more.

The controlled application of water for agricultural purposes through manmade systems to supply water requirements not satisfied by rainfall.

Irrigation water use
Water application on lands to assist in the growing of crops and pastures or to maintain vegetative growth in recreational lands, such as parks and golf courses.

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Jackson Turbidity Unit (JTU)
The JTU is a measurement of the turbidity, or lack of transparency, of water. It is measured by lighting a candle under a cylindrical transparent glass tube and pouring a sample of water into the tube until an observer looking from the top of the tube cannot see the image of the candle flame.

Jet stream
A high-speed, meandering wind current, generally moving from a westerly direction at speeds often exceeding 400 kilometers (250 miles) per hour at altitudes of 15 to 25 kilometers (10 to 15 miles).

A condition easily recognized by its symptoms of yellowed skin due to an accumulation of bilirubin in the body. Jaundice is often seen in liver disease such as hepatitis or liver cancer and can indicate other potentially serious conditions.

Junior Water Appropriator
The holder of a surface, or ground-water right that was acquired subsequent to other water rights on the same stream or aquifer.

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One thousand grams.

Kilowatthour (KWH)
A power demand of 1,000 watts for one hour. Power company utility rates are typically expressed in cents per kilowatt-hour.

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The process by which soluble materials in the soil, such as salts, nutrients, pesticide chemicals or contaminants, are washed into a lower layer of soil or are dissolved and carried away by water.

Lead is a soft malleable metal in the carbon group and is counted as one of the heavy metals. The most important use of lead is in the manufacture of lead-acid storage batteries, commonly used in a car battery. Lead is sometimes used in household plumbing which allows water to easily be contaminated with the metal. Lead consumption has short term and long term health effects and should be filtered out with a water filtration system before water is suitable to drink.

Lentic waters
Ponds or lakes (standing water).

A natural or manmade earthen barrier along the edge of a stream, lake, or river. Land alongside rivers can be protected from flooding by levees.

The study of inland waters such as biological, chemical, physical, geological, fresh water, etc. A limnologist studies both the aquatic system and the surrounding environment by observing how the body of water interacts with its watershed and how the changes in the environment affect the water.

Litmus Paper
A particular dye on paper that turns red under acidic conditions and blue under alkaline conditions. It is most commonly used to test the pH, or acidity and alkalinity of liquids. For example, it turns red in lemon water and blue in soapy water.

Livestock water use
Water used for livestock watering, feed lots, dairy operations, fish farming, and other on-farm needs.

Lotic waters
Flowing waters, as in streams and rivers.

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A chemical element which is known as an alkaline earth metal abundant in earth's crust. Magnesium is found in the body where it is stored half in the bones and half in the other organs and cells and is crucial for normal muscle and nerve function. Magnesium is also related to strong bones and a healthy immune system.

Malignant Cells
Cells that tend to be threatening to life which spread and destroy nearby tissue. These cells eventually spread beyond the tissue or organ in which it originated.

A chemical element with important industrial metal uses, particularly in stainless steel. Manganese is also present in tiny amounts in the body and serves to help the body form connective tissue, bone, blood clotting, carbohydrate metabolism, calcium absorption, and blood sugar regulation. When manganese is found in water it produces extremely dark stains and causes deposit to collect in the pipes. Light concentrations of manganese in water can be removed by a water softener and higher concentrations may be removed by oxidizing filters.

Maximum contaminant level (MCL)
The designation given by the U.S. Environmental Protection Agency (EPA) to water-quality standards promulgated under the Safe Drinking Water Act. The MCL is the greatest amount of a contaminant that can be present in drinking water without causing a risk to human health.

A heavy silvery element that is the only metal that is liquid at standard conditions for temperature and pressure. Mercury is used in thermometers, barometers, manometers, and other scientific apparatus. Mercury is typically released from industrial processes, agricultural processes, or commercial and medical products and can enter drinking water systems. High levels of mercury consumption can cause kidney damage.

The chemical reactions in the body that convert the fuel from food into energy, and determine how efficiently you burn that fuel. Whether you are eating, sleeping, or running your body is constantly burning calories to keep you going. In order to increase your metabolism it is important to exercise and to eat a lower fat diet. As you get older your metabolism will slow down which makes it easier to gain weight. Keep in mind that the energy burning process of metabolism needs water to work effectively.

Milligram (mg)
One-thousandth of a gram.

Milligrams per liter (mg/l)
A unit of the concentration of a constituent in water or wastewater. It represents 0.001 gram of a constituent in 1 liter of water. It is approximately equal to one part per million (PPM).

Million gallons per day (Mgd)
A rate of flow of water equal to 133,680.56 cubic feet per day, or 1.5472 cubic feet per second, or 3.0689 acre-feet per day. A flow of one million gallons per day for one year equals 1,120 acre-feet (365 million gallons).

A natural occurring solid chemical substance formed through biogeochemical processes with a crystalline structure. Minerals help your body with many different functions and are essential in growth and maintaining health.

Mining water use
Water use during quarrying rocks and extracting minerals from the land.

Municipal water system
A water system that has at least five service connections or which regularly serves 25 individuals for 60 days; also called a public water system

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Nephelometric turbidity unit (NTU)
Unit of measure for the turbidity of water. Essentially, a measure of the cloudiness of water as measured by a nephelometer. Turbidity is based on the amount of light that is reflected off particles in the water.

A chemical that can be found in some public or private drinking water supplies. Nitrates are oxygen chemical units which combine with other various organic and inorganic compounds. Once taken into the body, nitrates are converted into nitrites. The greatest use of nitrates is as a fertilizer. Nitrates are very soluble and do not bind to soil and are likely to to remain in water until consumed by plants or other organisms.

National Geodetic Vertical Datum. (1) As corrected in 1929, a vertical control measure used as a reference for establishing varying elevations. (2) Elevation datum plane previously used by the Federal Emergency Management Agency (FEMA) for the determination of flood elevations. FEMA current uses the North American Vertical Datum Plane.

NGVD of 1929
National Geodetic Vertical Datum of 1929. A geodetic datum derived from a general adjustment of the first order level nets of the United States and Canada. It was formerly called "Sea Level Datum of 1929" or "mean sea level" in the USGS series of reports. Although the datum was derived from the average sea level over a period of many years at 26 tide stations along the Atlantic, Gulf of Mexico, and Pacific Coasts, it does not necessarily represent local mean sea level at any particular place.

Non-point source (NPS) pollution
Pollution discharged over a wide land area, not from one specific location. These are forms of diffuse pollution caused by sediment, nutrients, organic and toxic substances originating from land-use activities, which are carried to lakes and streams by surface runoff. Non-point source pollution is contamination that occurs when rainwater, snowmelt, or irrigation washes off plowed fields, city streets, or suburban backyards. As this runoff moves across the land surface, it picks up soil particles and pollutants, such as nutrients and pesticides.

A chemical that an organism needs in order to live and grow. Nutrients are used to build and repair tissues, regulate body processes, and are used to convert and use energy in the body. Some nutrients include carbohydrates, fats, proteins, and vitamins. It is best to consume the most natural nutrients as well as a variety of nutrients and not just the same kind.

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Organic matter
Plant and animal residues, or substances made by living organisms. All are based upon carbon compounds.

The movement of water molecules through a thin membrane. The osmosis process occurs in our bodies and is also one method of desalinating saline water.

A type of arthritis that causes the cartilage in between joints to breakdown and eventually deteriorate. This causes immense pain because the bones and joints will rub against each other without any cushion. Highly acidic foods are said to bring on osteoarthritis symptoms so there is an alkaline diet developed to lower acidity in ones body by avoiding acidic food and drinks.

The most common type of bone disease which occurs when the body fails to form enough new bone, or when too much old bone is reabsorbed by the body or both. The most common symptoms of osteoporosis is a hunched back and fracture in the bones. Calcium and phosphate are two essential minerals for the growth of bones that are used to grow bones throughout our lifetime. As time goes by the body absorbs these two minerals which makes the bone tissue weaker.

The place where a sewer, drain, or stream discharges; the outlet or structure through which reclaimed water or treated effluent is finally discharged to a receiving water body.

The combination of a substance with oxygen. A reaction in which atoms in an element lose electrons and the valence of the element is correspondingly increased. The liver eliminates 90-95% of the alcohol by oxidation of the alcohol to carbon dioxide and water.

Oxygen demand
The need for molecular oxygen to meet the needs of biological and chemical processes in water. Even though very little oxygen will dissolve in water, it is extremely important in biological and chemical processes.

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Particle size
The diameter, in millimeters, of suspended sediment or bed material.
Particle-size classifications are:
[1] Clay—0.00024-0.004 millimeters (mm);
[2] Silt—0.004-0.062 mm;
[3] Sand—0.062-2.0 mm; and
[4] Gravel—2.0-64.0 mm.

Parts per billion
The number of "parts" by weight of a substance per billion parts of water. Used to measure extremely small concentrations.

Parts per million
The number of "parts" by weight of a substance per million parts of water. This unit is commonly used to represent pollutant concentrations.

A process that uses heat at a specific temperature to destroy bacteria which slows the microbial growth in food. Pasteurization does not aim to kill all micro-organisms in the food, it aims to reduce the viable pathogens so they are unlikely to cause disease.

A disease-producing agent; usually applied to a living organism. Generally, any viruses, bacteria, or fungi that cause disease.

Peak flow
The maximum instantaneous discharge of a stream or river at a given location. It usually occurs at or near the time of maximum stage.

Per capita use
The average amount of water used per person during a standard time period, generally per day.

Both a natural and man made chemical used to produce rocket fuel, explosives, fireworks, which is also present in bleach and some fertilizers. The use of this salt can be released into the environment which is why the EPA has decided to regulate perchlorate under the Safe Drinking Water Act.

(1) The movement of water through the openings in rock or soil. (2) the entrance of a portion of the streamflow into the channel materials to contribute to ground water replenishment.

The ability of a material to allow the passage of a liquid, such as water through rocks. Permeable materials, such as gravel and sand, allow water to move quickly through them, whereas unpermeable material, such as clay, don't allow water to flow freely.

The production of water and and other various dissolved solids excreted by the sweat glands in the skin. Toxins are excreted through perspiration and is our body's way of cooling itself down. Emotional induced sweating will occur in the armpits, hands, soles or foreheads while physical induced sweating will occur throughout the body. It is important to drink plenty of water to balance the loss of water through perspiration.

Chemicals, biological agents, antimicrobial's, or disinfectants that are designed to repel, control, attract, and then terminate pests. Pests include insects, weeds, birds, mammals, fish, and more. Pesticides are one of the causes of water pollution, and some of the pesticides are persistent organic pollutants which can contribute to soil pollution.

A measure of the relative acidity or alkalinity of water. Water with a pH of 7 is neutral; lower pH levels indicate increasing acidity, while pH levels higher than 7 indicate increasingly basic solutions.

pH balance
pH is a measure of the acidity or alkalinity of an aqueous solution and is a good indicator of whether water is hard or soft. Pure water is said to be at a pH of 7, pH lower than 7 is said to be acidic and greater than 7 is considered alkaline. The measure of pH and alkalinity is needed to determine the corrosiveness of water.

A liquid secreted by the mucous membranes produced by the respiratory system and discharged through the mouth. The color can range from dark yellow and green to dark brown depending on the constituents. Phlegm is always produced throughout the body but is more noticeable when one is coughing during a period of sickness.

An inorganic material which is found in many foods and preservatives. Phosphates are often used to prevent scale formation and corrosion (Iron & Manganese) in water distribution systems. It is also used to reduce lead and copper in drinking water. Studies have shown that high levels of phosphate in the body have been linked to cardiovascular disease and other health issues.

A man made element used to make nuclear weapons. Testing of these nuclear weapons has caused plutonium to be dispersed into the environments soil. As plutonium decays it releases radiation and forms other radioactive isotopes which can contaminate food, water, and soil. Plutonium that reaches the body generally stays in the body for decades and can expose tissue to radiation.

An inflammatory condition of the lung associated with fever, chest symptoms, and lack of air space. Pneumonia is caused by several factors including bacteria, viruses, fungi, and parasites. Symptoms are cough, chest pain, fever and difficulty breathing.

Point of Entry Disinfection Unit
When the unit is installed on your main water line to purify all the water in your home. Unlike the point of use, which is where water is purified only on a single faucet.

Point-source pollution
Water pollution coming from a single point, such as a sewage-outflow pipe.

Polychlorinated Biphenyls (PCBs)
A group of synthetic, toxic industrial chemical compounds once used in making paint and electrical transformers, which are chemically inert and not biodegradable. PCBs were frequently found in industrial wastes, and subsequently found their way into surface and ground waters. As a result of their persistence, they tend to accumulate in the environment. In terms of streams and rivers, PCBs are drawn to sediment, to which they attach and can remain virtually indefinitely. Although virtually banned in 1979 with the passage of the Toxic Substances Control Act, they continue to appear in the flesh of fish and other animals.

A measure of the water-bearing capacity of subsurface rock. With respect to water movement, it is not just the total magnitude of porosity that is important, but the size of the voids and the extent to which they are interconnected, as the pores in a formation may be open, or interconnected, or closed and isolated. For example, clay may have a very high porosity with respect to potential water content, but it constitutes a poor medium as an aquifer because the pores are usually so small.

Potable water
Water of a quality suitable for drinking.

Potassium is an important mineral to the normal functioning of your body and works with other minerals to keep the body's water level balanced. Potassium levels in the body are regulated by the kidneys and excess potassium is excreted in the urine to maintain balance.

Rain, snow, hail, sleet, dew, and frost.

Primary wastewater treatment
The first stage of the wastewater-treatment process where mechanical methods, such as filters and scrapers, are used to remove pollutants. Solid material in sewage also settles out in this process.

Prior appropriation doctrine
The system for allocating water to private individuals used in most Western states. The doctrine of Prior Appropriation was in common use throughout the arid West as early settlers and miners began to develop the land. The prior appropriation doctrine is based on the concept of "First in Time, First in Right." The first person to take a quantity of water and put it to beneficial use has a higher priority of right than a subsequent user. The rights can be lost through nonuse; they can also be sold or transferred apart from the land. Contrasts with riparian water rights.

Private Well
A family or individual's personal access to water that comes from a well. EPA does not have the authority to regulate the water quality of private water wells which can cause hazardous health issues because the water may be contaminated.

Public supply
Water withdrawn by public governments and agencies, such as a county water department, and by private companies that is then delivered to users. Public suppliers provide water for domestic, commercial, thermoelectric power, industrial, and public water users. Most people's household water is delivered by a public water supplier. The systems have at least 15 service connections (such as households, businesses, or schools) or regularly serve at least 25 individuals daily for at least 60 days out of the year.

Public water use
Water supplied from a public-water supply and used for such purposes as firefighting, street washing, and municipal parks and swimming pools.

The specialty that deals with the diseases of the respiratory tract.

Purified Water
Water from any source that is physically processed to remove impurities. Drinking water is expected to have contaminants that can cause several problems over time. Which makes it important to have access to purified water in order to avoid these contaminants and protect your health.

Putrefaction is the bacterial or fungal decomposition of organic matter with resulting obnoxious odors.

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Quantification limit
The lower limit to the range in which the concentration of a solute can be determined by a particular analytical instrument.

Quarry water
The moisture content of freshly quarried stone, esp. if porous.

Quarter-flow interval
The shortest period of time in days (typically) during which one-quarter of the annual runoff occurs.

(1) Sand that is unstable due to the upward pressure of water. (2) Sand easily moved or readily yielding to pressure, especially a deep mass of loose sand mixed with water, very dangerous from the difficulty of extricating anything that begins sinking into it.

The part of a stream that has a strong current; an artificial current or bubbling patch of water just astern of a moving boat.

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A naturally occurring silvery-white radioactive material that can exist in several forms called isotopes found in soil, rocks, plants, and foods at low levels. Surface water is generally low in radium but groundwater can contain significant amounts. Most people are exposed to radium levels daily and it is insignificant to their health, however high levels of exposure can lead to tissue and bone cancer.

A naturally occurring silvery-white radioactive material that can exist in several forms called isotopes found in soil, rocks, plants, and foods at low levels. Surface water is generally low in radium but groundwater can contain significant amounts. Most people are exposed to radium levels daily and it is insignificant to their health, however high levels of exposure can lead to tissue and bone cancer.

Rating curve
A drawn curve showing the relation between gage height and discharge of a stream at a given gaging station.

Water added to an aquifer. For instance, rainfall that seeps into the ground.

Reclaimed wastewater
Treated wastewater that can be used for beneficial purposes, such as irrigating certain plants.

Recycled water
Water that is used more than one time before it passes back into the natural hydrologic system.

A pond, lake, or basin, either natural or artificial, for the storage, regulation, and control of water.

Return flow
(1) That part of a diverted flow that is not consumptively used and returned to its original source or another body of water. (2) (Irrigation) Drainage water from irrigated farmlands that re-enters the water system to be used further downstream.

Return flow (irrigation)
Irrigation water that is applied to an area and which is not consumed in evaporation or transpiration and returns to a surface stream or aquifer.

Reverse Osmosis
(1) (Desalination) The process of removing salts from water using a membrane. With reverse osmosis, the product water passes through a fine membrane that the salts are unable to pass through, while the salt waste (brine) is removed and disposed. This process differs from electrodialysis, where the salts are extracted from the feedwater by using a membrane with an electrical current to separate the ions. The positive ions go through one membrane, while the negative ions flow through a different membrane, leaving the end product of freshwater. (2) (Water Quality) An advanced method of water or wastewater treatment that relies on a semi-permeable membrane to separate waters from pollutants. An external force is used to reverse the normal osmotic process resulting in the solvent moving from a solution of higher concentration to one of lower concentration.

Any variety of disorders marked by inflammation, degeneration, or metabolic derangement of the connective tissue structures. Often accompanied by pain, stiffness, or limitation of movement in joints and related structures. Most often people associate rheumatism with arthritis, rheumatic fever, or a complication of strep throat.

A deficiency disease resulting from the lack of Vitamin D, calcium, or lack of exposure to sunlight. It is characterized by the softening of developing bone, malnutrition, and enlargement of the liver and spleen. Rickets is uncommon in the United States but is a frequent childhood disease in developing countries because of the lack of calcium and phosphate available.

Riparian water rights
The rights of an owner whose land abuts water. They differ from state to state and often depend on whether the water is a river, lake, or ocean. The doctrine of riparian rights is an old one, having its origins in English common law. Specifically, persons who own land adjacent to a stream have the right to make reasonable use of the stream. Riparian users of a stream share the streamflow among themselves, and the concept of priority of use (Prior Appropriation Doctrine) is not applicable. Riparian rights cannot be sold or transferred for use on nonriparian land.

A natural stream of water of considerable volume, larger than a brook or creek.

RO Permeate
Reverse osmosis permeate, the point at which the water flows through the pores of the membrane to remove chlorine, dust, rust, and other particles.

(1) That part of the precipitation, snow melt, or irrigation water that appears in uncontrolled surface streams, rivers, drains or sewers. Runoff may be classified according to speed of appearance after rainfall or melting snow as direct runoff or base runoff, and according to source as surface runoff, storm interflow, or ground-water runoff. (2) The total discharge described in (1), above, during a specified period of time. (3) Also defined as the depth to which a drainage area would be covered if all of the runoff for a given period of time were uniformly distributed over it.

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Saline water
Water that contains significant amounts of dissolved solids.
Here are our parameters for saline water:
Fresh water - Less than 1,000 parts per million (ppm)
Slightly saline water - From 1,000 ppm to 3,000 ppm
Moderately saline water - From 3,000 ppm to 10,000 ppm
Highly saline water - From 10,000 ppm to 35,000 ppm

Is the amount of salt dissolved in a body of water. The higher the salinity the more salt it has may it be sodium chloride, magnesium, or calcium sulfates.

Scale Deposits
Hard water is known to leave behind scale deposits on dishes, sinks, toilets, etc. Scale deposits are composed mainly of calcium and magnesium. The build up of these deposits can restrict the flow of water in pipes over time. This is why it is often preferred to use soft water to prevent the damages due from scale deposits.

A disease caused by the deficiency of Vitamin C. Scurvy is rare in countries where fresh fruits and vegetables are readily available. Scurvy's symptoms are often lethargy, spots on the skin, spongy gums, fever, loss of teeth, and bleeding from the mucous membranes.

Secondary wastewater treatment
Treatment (following primary wastewater treatment) involving the biological process of reducing suspended, colloidal, and dissolved organic matter in effluent from primary treatment systems and which generally removes 80 to 95 percent of the Biochemical Oxygen Demand (BOD) and suspended matter. Secondary wastewater treatment may be accomplished by biological or chemical-physical methods. Activated sludge and trickling filters are two of the most common means of secondary treatment. It is accomplished by bringing together waste, bacteria, and oxygen in trickling filters or in the activated sludge process. This treatment removes floating and settleable solids and about 90 percent of the oxygen-demanding substances and suspended solids. Disinfection is the final stage of secondary treatment.

Usually applied to material in suspension in water or recently deposited from suspension. In the plural the word is applied to all kinds of deposits from the waters of streams, lakes, or seas.

Sedimentary rock
Rock formed of sediment, and specifically: (1) sandstone and shale, formed of fragments of other rock transported from their sources and deposited in water; and (2) rocks formed by or from secretions of organisms, such as most limestone. Many sedimentary rocks show distinct layering, which is the result of different types of sediment being deposited in succession.

Sedimentation tanks
Wastewater tanks in which floating wastes are skimmed off and settled solids are removed for disposal.

Self-supplied water
Water withdrawn from a surface- or ground-water source by a user rather than being obtained from a public supply. An example would be homeowners getting their water from their own well.

(1) The slow movement of water through small cracks, pores, Interstices, etc., of a material into or out of a body of surface or subsurface water. (2) The loss of water by infiltration into the soil from a canal, ditches, laterals, watercourse, reservoir, storage facilities, or other body of water, or from a field.

A severe illness in which the bloodstream is overwhelmed by bacteria. The body may develop an inflammatory response by the immune system to microbes in the blood, urine, lungs, and skin. Sepsis causes the blood pressure to drop which causes major organs and body systems to stop working properly.

Septic tank
A tank used to detain domestic wastes to allow the settling of solids prior to distribution to a leach field for soil absorption. Septic tanks are used when a sewer line is not available to carry them to a treatment plant. A settling tank in which settled sludge is in immediate contact with sewage flowing through the tank, and wherein solids are decomposed by anaerobic bacterial action.

Settling pond (water quality)
An open lagoon into which wastewater contaminated with solid pollutants is placed and allowed to stand. The solid pollutants suspended in the water sink to the bottom of the lagoon and the liquid is allowed to overflow out of the enclosure.

Sewage treatment plant
A facility designed to receive the wastewater from domestic sources and to remove materials that damage water quality and threaten public health and safety when discharged into receiving streams or bodies of water. The substances removed are classified into four basic areas:
[1] greases and fats;
[2] solids from human waste and other sources;
[3] dissolved pollutants from human waste and decomposition products; and
[4] dangerous microorganisms.
Most facilities employ a combination of mechanical removal steps and bacterial decomposition to achieve the desired results. Chlorine is often added to discharges from the plants to reduce the danger of spreading disease by the release of pathogenic bacteria.

A system of underground pipes that collect and deliver wastewater to treatment facilities or streams.

A compound containing a silicon bearing anion, known to be present in all living organisms. The earth's crust contains 80-90% silicates as well as other compounds. Water moving over natural deposits will dissolve a small amount of silicate minerals, making silicates a common contaminant of most waters. Silicon is found in products such as detergent, stoneware, wood, cement, etc.

A depression in the Earth's surface caused by dissolving of underlying limestone, salt, or gypsum. Drainage is provided through underground channels that may be enlarged by the collapse of a cavern roof.

Not intoxicated or drunk, especially in the use of liquor. Water is the best beverage to drink when trying to become sober because it hydrates the body and reduces and slows down drunkenness.

Sodium is a major mineral necessary to regulate blood pressure and fluid volume. It is also important in maintaining the balance of pH levels. Sodium is essential in the body but must not be taken in excess amounts. The more sodium you consume, the more water your body will retain which can result in bloating and high blood pressure.

Sodium Carbonate
Also known as washing soda or soda ash, is a sodium salt of carbonic acid. It is known for its everyday use as a water softener. Sodium Carbonate is also used as a pH regulator to maintain stable alkaline conditions.

Sodium Sulfate
The sodium salt of sulfuric acid (Na2SO4), the most important mineral in the chemicals industry. Sodium sulfate is used to make soaps, detergents, glass, and paper.

Soft Water
Water treated in which the only ion is sodium. In comparison to hard water, soft water contains less calcium and other deposits. It may taste salty but is preferred in homes because it does not damage sinks and faucets with deposits as hard water is known to do. A great advantage of soft water is that it is known to save users money because it requires less soap when showering or washing clothes. Soft water is also known to leave less film deposits on dishes and bathroom areas.

A substance that is dissolved in another substance, thus forming a solution.

A mixture of a solvent and a solute. In some solutions, such as sugar water, the substances mix so thoroughly that the solute cannot be seen. But in other solutions, such as water mixed with dye, the solution is visibly changed.

A substance that dissolves other substances, thus forming a solution. Water dissolves more substances than any other, and is known as the "universal solvent".

Specific conductance
A measure of the ability of water to conduct an electrical current as measured using a 1-cm cell and expressed in units of electrical conductance, i.e., Siemens per centimeter at 25 degrees Celsius. Specific conductance can be used for approximating the total dissolved solids content of water by testing its capacity to carry an electrical current. In water quality, specific conductance is used in ground water monitoring as an indication of the presence of ions of chemical substances that may have been released by a leaking landfill or other waste storage or disposal facility. A higher specific conductance in water drawn from downgradient wells when compared to upgradient wells indicates possible contamination from the facility.

Spray irrigation
An common irrigation method where water is shot from high-pressure sprayers onto crops. Because water is shot high into the air onto crops, some water is lost to evaporation.

A water body formed when the side of a hill, a valley bottom or other excavation intersects a flowing body of groundwater at or below the local water table, below which the subsurface material is saturated with water.

Storm sewer
A sewer that carries only surface runoff, street wash, and snow melt from the land. In a separate sewer system, storm sewers are completely separate from those that carry domestic and commercial wastewater (sanitary sewers).

A general term for a body of flowing water; natural water course containing water at least part of the year. In hydrology, it is generally applied to the water flowing in a natural channel as distinct from a canal.

The water discharge that occurs in a natural channel. A more general term than runoff, streamflow may be applied to discharge whether or not it is affected by diversion or regulation.

The waste product of the human digestive system, also known as human feces. Infection with E. coli can be diagnosed by detecting the bacterium in the stool, mostly commonly detected by bloody stool.

A dropping of the land surface as a result of ground water being pumped. Cracks and fissures can appear in the land. Subsidence is virtually an irreversible process.

Sulfuric Acid
Clear, colorless, odorless liquid that is very corrosive. Agricultural fertilizer represent the largest use for sulfuric acid, but other uses consist of dyes, alcohols, plastics, rubber, glue, film, drugs, explosives, soaps, paper, and pharmaceutical products. Sulfuric acid reacts violently with water and if it gets on your skin it immediately begins to take water out of the skin which causes acid burn.

Surface tension
The attraction of molecules to each other on a liquid's surface. Thus, a barrier is created between the air and the liquid.

Surface water
Water that is on the Earth's surface, such as in a stream, river, lake, or reservoir.

Suspended sediment
Very fine soil particles that remain in suspension in water for a considerable period of time without contact with the bottom. Such material remains in suspension due to the upward components of turbulence and currents and/or by suspension.

Suspended-sediment concentration
The ratio of the mass of dry sediment in a water-sediment mixture to the mass of the water-sediment mixture. Typically expressed in milligrams of dry sediment per liter of water-sediment mixture.

Suspended-sediment discharge
The quantity of suspended sediment passing a point in a stream over a specified period of time. When expressed in tons per day, it is computed by multiplying water discharge (in cubic feet per second) by the suspended-sediment concentration (in milligrams per liter) and by the factor 0.0027.

Suspended solids
Solids that are not in true solution and that can be removed by filtration. Such suspended solids usually contribute directly to turbidity. Defined in waste management, these are small particles of solid pollutants that resist separation by conventional methods.

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Tertiary wastewater treatment
Selected biological, physical, and chemical separation processes to remove organic and inorganic substances that resist conventional treatment practices; the additional treatment of effluent beyond that of primary and secondary treatment methods to obtain a very high quality of effluent. The complete wastewater treatment process typically involves a three-phase process: (1) First, in the primary wastewater treatment process, which incorporates physical aspects, untreated water is passed through a series of screens to remove solid wastes; (2) Second, in the secondary wastewater treatment process, typically involving biological and chemical processes, screened wastewater is then passed a series of holding and aeration tanks and ponds; and (3) Third, the tertiary wastewater treatment process consists of flocculation basins, clarifiers, filters, and chlorine basins or ozone or ultraviolet radiation processes.

Thermal pollution
A reduction in water quality caused by increasing its temperature, often due to disposal of waste heat from industrial or power generation processes. Thermally polluted water can harm the environment because plants and animals can have a hard time adapting to it.

Thermoelectric power water use
Water used in the process of the generation of thermoelectric power. Power plants that burn coal and oil are examples of thermoelectric-power facilities.

Total Dissolved Solids
The measure of the combined content of all inorganic and organic substances. The principle use of TDS is in the application of water quality for streams, rivers, and lakes to indicate the presence of chemical contaminants in the water. Primary sources of TDS in water come from natural sources, sewage, urban run-off, industrial wastewater, and chemicals used in the water treatment process. A high concentration of TDS does not pose a health risk but it does affect the aesthetic quality of the water, interfere with washing clothes and corroding plumbing fixtures.

Transmissibility (ground water)
The capacity of a rock to transmit water under pressure. The coefficient of transmissibility is the rate of flow of water, at the prevailing water temperature, in gallons per day, through a vertical strip of the aquifer one foot wide, extending the full saturated height of the aquifer under a hydraulic gradient of 100-percent. A hydraulic gradient of 100-percent means a one foot drop in head in one foot of flow distance.

Process by which water that is absorbed by plants, usually through the roots, is evaporated into the atmosphere from the plant surface, such as leaf pores. See evapotranspiration.

Organic chemical that often occurs in drinking water as a result of chlorine treatment for disinfectant purposes, therefore known as disinfection byproducts. Trihalomethanes are environmental pollutants and are considered cancer causing. THMs may be absorbed into the body by inhalation, ingestion, and through the skin.

An antibacterial and antifungal agent that is used in many consumer products that we use on a daily basis. It is popular in hand soaps, toothpaste, utensils, toys, etc. It is one of the most detected elements in wastewater because it degrades very slowly. It is a current dispute that triclosan may be carcinogenic.

Tri-Sodium Phosphate
A white, granular or crystalline solid, highly soluble in water producing an alkaline solution. It is a cleaning agent, food additive, stain remover, and degreaser. TSP is generally not good for cleaning bathrooms because it can corrode pipes.

A smaller river or stream that flows into a larger river or stream. Usually, a number of smaller tributaries merge to form a river.

An infectious disease that may affect almost any tissue of the body especially the lungs. Tuberculosis can affect anyone of age and is spread through air by those who are untreated.

The amount of solid particles that are suspended in water and that cause light rays shining through the water to scatter. Thus, turbidity makes the water cloudy or even opaque in extreme cases. Turbidity is measured in nephelometric turbidity units (NTU).

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Unsaturated zone
The zone immediately below the land surface where the pores contain both water and air, but are not totally saturated with water. These zones differ from an aquifer, where the pores are saturated with water.

Urban Runoff
The water that has drained from man-made surfaces such as roads, freeways, sidewalks, airports, roofs, and industrial sites among others. This runoff carries many different types of contaminants such as bacteria, oil, grease, and many other toxic chemicals. This runoff poses a threat to human health because it is a source of contamination to drinking water.

Uric Acid
Uric acid is a chemical created when the body breaks down substances called pureness found in assorted foods and drinks. Most uric acid passes out in urine but if your body produces too much uric acid or does not remove enough of it, it can result in illness. Keeping your body hydrated by drinking plenty of water throughout the day can help prevent the build up of uric acid by releasing it through urine.

A condition in which crystals in the urine combine to form stones found anywhere in the urinary tract. These stones cause irritation and discomfort and mostly end up in the bladder. It is recommended to increase water intake to assist the stone to pass through the urinary system.

Uterine Hemorrhages
When bleeding occurs in the uterus, sometimes caused by complicated childbirths or fibroids.

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State or EPA permission not to meet a certain drinking water standard. The water system must prove that: (1) it cannot meet a MCL, even while using the best available treatment method, because of the characteristics of the raw water, and (2) the variance will not create an unreasonable risk to public health. The State or EPA must review, and allow public comment on, a variance every three years. States can also grant variances to water systems that serve small populations and which prove that they are unable to afford the required treatment, an alternative water source, or otherwise comply with the standard.

A failure to meet any state or federal drinking water regulation.

Vitamin B Complex
A group of 8 water soluble vitamins that play a vital role in cell metabolism. Vitamin B complex is important to enhance immune and nervous system function, maintain healthy skin, promote cell growth and division, prevent anemia, and reduce the risk of pancreatic cancer. (Ex: Vitamin B1, B2, B3...etc)

Vulnerability Assessment
An evaluation of drinking water source quality and its vulnerability to contamination by pathogens and toxic chemicals.

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Water that has been used in homes, industries, and businesses that is not for reuse unless it is treated.

Wastewater-treatment return flow
Water returned to the environment by wastewater-treatment facilities.

Water cycle
The circuit of water movement from the oceans to the atmosphere and to the Earth and return to the atmosphere through various stages or processes such as precipitation, interception, runoff, infiltration, percolation, storage, evaporation, and transportation.

Disease caused by pathogenic microorganisms which are directly transmitted when contaminated fresh water is consumed. Water borne diseases are spread by contamination of drinking water systems with the urine and feces of infected animal or people. This is likely to occur from runoff from landfills, septic fields, sewer pipes, or any surface water.

Water quality
A term used to describe the chemical, physical, and biological characteristics of water, usually in respect to its suitability for a particular purpose.

Water quality report
A status report on the quality of water in any given area. Different standards are required for different water body uses such as swimming, drinking, showering, etc. It is important to monitor these water qualities to protect our health. The three most common pollutants found in water are dirt, bacteria, and nutrients.

Water table
The top of the water surface in the saturated part of an aquifer.

Water use
Water that is used for a specific purpose, such as for domestic use, irrigation, or industrial processing. Water use pertains to human's interaction with and influence on the hydrologic cycle, and includes elements, such as water withdrawal from surface- and ground-water sources, water delivery to homes and businesses, consumptive use of water, water released from wastewater-treatment plants, water returned to the environment, and instream uses, such as using water to produce hydroelectric power.

The land area that drains water to a particular stream, river, or lake. It is a land feature that can be identified by tracing a line along the highest elevations between two areas on a map, often a ridge. Large watersheds, like the Mississippi River basin contain thousands of smaller watersheds.

Watthour (Wh)
An electrical energy unit of measure equal to one watt of power supplied to, or taken from, an electrical circuit steadily for one hour.

Well (water)
An artificial excavation put down by any method for the purposes of withdrawing water from the underground aquifers. A bored, drilled, or driven shaft, or a dug hole whose depth is greater than the largest surface dimension and whose purpose is to reach underground water supplies or oil, or to store or bury fluids below ground.

Water removed from a ground- or surface-water source for use.

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A method of landscaping that uses plants that are well adapted to the local area and are drought-resistant. Xeriscaping is becoming more popular as a way of saving water at home.
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Mass per unit time per unit area.
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Zebra mussel
The zebra mussel, a freshwater Eurasian lamellibranch mollusk (Dreissena polymorpha), is a marine shellfish which was first discovered in the Great Lakes of the United States in 1988 and is believed to have arrived in North America by being carried in the ballast water of a cargo vessel. Since the first discovery of this exotic species, they have spread rapidly through North American surface waters, particularly throughout the Great Lakes and Mississippi River basins and their navigable tributaries. As of March 1996, zebra mussels were resident in nineteen states and two Canadian provinces. Zebra mussels can cause severe fouling of municipal drinking water, electric power generation, and industrial water systems; they are also harmful to aquatic ecosystems, boating and navigation, agricultural irrigation equipment, aquacultural equipment, and recreation beach use.

Zero discharge
The goal, in the preamble to the Clean Water Act (CWA), of zero pollutants in water discharges.

A metallic chemical element that is an essential mineral to human health as well as for its use of galvanization. Galvanization is the process of coating other metals with iron or steel. Zinc supports your healthy immune system and is essential for wound healing. Zinc deficiencies can cause health issues such as growth retardation, hair loss, delayed sexual maturation, and many more. Zinc may leach from galvanized water pipes and into drinking water systems which may pose health threats.

The partition of a city, county, township, or other governmental unit or area by ordinance into sections reserved for different land-use purposes, such as residential, business, manufacturing, greenbelt, or agriculture.

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