Water and Water Supply Systems and Water Treatment Methods

Water

Essential resource that sustains life and is the fundamental component of plumbing and water supply systems.

Hydrosphere

The part of Earth where water exists in oceans, rivers, lakes, groundwater, reservoirs, and the atmosphere.

Groundwater

Water stored beneath the Earth's surface in aquifers that can be extracted for human use.

Groundwater Preservation

The protection of groundwater from contamination because recovery may take decades once polluted.

Hydrologic Cycle

The continuous movement of water through evaporation, condensation, precipitation, infiltration, surface runoff, and subsurface flow.

Evaporation

The process where liquid water changes into water vapor.

Condensation

The process where water vapor cools and changes into liquid droplets.

Precipitation

Water falling from the atmosphere as rain, snow, sleet, or hail.

Infiltration

The movement of water from the ground surface into the soil.

Surface Runoff

Water flowing over the land surface toward rivers, lakes, or oceans.

Subsurface Flow

The movement of infiltrated water beneath the ground.

Heat Capacity

The ability of water to absorb large amounts of heat without a significant increase in temperature.

Surface Tension

The tendency of water molecules to stick together, allowing water to support small objects on its surface.

Capillarity

The ability of water to move upward through narrow spaces against gravity.

Universal Solvent

A property of water that allows it to dissolve almost any substance.

Natural Water

Water found naturally from precipitation that often contains physical, chemical, biological, or radiological impurities.

Purified Water

Water that has undergone physical, biological, or chemical treatment to improve its quality.

Contaminated Water

Water containing substances that reduce its quality and may affect human health.

Polluted Water

Water containing foreign substances that impair potability and create health hazards.

Hard Water

Water containing calcium, magnesium, iron, or aluminum that makes soap difficult to lather and causes scale deposits.

Soft Water

Water lacking calcium and magnesium, making it easy to produce lather and preventing scale formation.

Grey Water

Wastewater from sinks, washbasins, showers, bathtubs, and laundries.

Black Water

Wastewater containing human waste from toilets and urinals.

Storm Water

Rainwater and surface runoff.

Nourishment Use of Water

Water supplies nutrients and minerals essential for sustaining life.

Cleansing and Hygiene Use

Water dissolves and carries away dirt and waste while providing comfortable bathing temperatures.

Ceremonial Use of Water

Water is used in religious purification rituals such as baptism and other ceremonies.

Transportation Use of Water

Waterways transport goods and passengers efficiently.

Cooling Medium

Water removes heat effectively because of its high heat capacity and evaporation properties.

Architectural Element

Water enhances landscaping through reflection, movement, sound, and support for aquatic life.

Protective Use of Water

Water is the primary medium used in firefighting and fire protection systems.

Sports and Recreation Use

Water supports swimming, boating, fishing, hot springs, and competitive water sports.

Therapeutic Use of Water

Water is used in hospitals for sanitation and in rehabilitation to reduce strain during therapy.

Power Generation

Flowing water is used in hydroelectric dams and mills to generate energy.

Industrial Application of Water

Water supports agriculture, aquaculture, transportation, and many industrial processes.

Water Quality

The measure of water's physical, chemical, biological, and radiological characteristics.

Physical Characteristics

Water quality factors including turbidity, color, taste, odor, temperature, and foamability.

Turbidity

The cloudiness of water caused by suspended particles such as clay, silt, plankton, or organic matter.

Color of Water

Usually caused by dissolved organic matter or microorganisms and may reduce aesthetic quality.

Taste and Odor

Usually caused by organic compounds and require chemical analysis to determine their source.

Ideal Water Temperature

Water supplied between 10–16°C (50–60°F) is generally preferred.

Foamability

The tendency of water to produce foam, usually due to detergent contamination.

Chemical Characteristics

Water quality factors related to dissolved minerals, salts, and chemical substances.

Alkalinity

The presence of carbonate, bicarbonate, and hydroxide compounds that determines water treatment methods.

Water Hardness

A condition caused by calcium and magnesium salts that reduces soap effectiveness and causes scaling.

Temporary Hardness

Hardness caused by carbonate salts that can be reduced by heating but still forms scale.

Permanent Hardness

Hardness caused mainly by bicarbonate salts that cannot be removed simply by heating.

Toxic Substances

Dangerous chemicals in water such as arsenic, barium, cadmium, cyanide, fluoride, lead, selenium, and silver.

Chlorides

Dissolved salts entering water from marine sediments, seawater intrusion, brine, or industrial wastes.

Copper in Water

Usually enters water from natural deposits or corrosion of copper pipes.

Iron in Water

Commonly found in groundwater and may result from corrosion of iron pipes.

Nitrates

Compounds that can cause Blue Baby Syndrome (methemoglobinemia) in infants when present at high concentrations.

Pesticides in Water

Chemicals that contaminate groundwater, especially near treated areas and wells.

Sodium in Water

May pose health risks for individuals with heart, kidney, or circulatory diseases.

Sulfates

Minerals that may have laxative effects and naturally occur in groundwater.

Biological Characteristics

Water quality factors involving disease-causing organisms such as bacteria, protozoa, and viruses.

E. coli

Bacteria indicating fecal contamination and posing serious health risks.

Protozoa

Microscopic organisms capable of contaminating water and causing disease.

Viruses

Nonliving infectious particles that cause diseases when present in water.

Radiological Characteristics

Water quality concerns caused by radioactive materials whose effects accumulate over time.

Surface Water

Water obtained from rivers, lakes, ponds, reservoirs, and surface runoff.

Aquifer

An underground water-bearing layer of soil or rock that stores groundwater.

Water Table

The upper level of groundwater in an aquifer where water stands in an unpumped well.

Well

An excavation made to withdraw groundwater using manual or mechanical methods.

Dug Well

A large-diameter well excavated manually or mechanically to depths of about 15 meters (50 feet).

Driven Well

A simple, inexpensive well made by driving a steel pipe into the ground up to about 15 meters deep.

Bored Well

A well constructed using earth augers, usually less than 30 meters deep and lined with metal, concrete, or tile.

Drilled Well

A deep well that may reach up to 300 meters using percussion, rotary drilling, or down-the-hole pneumatic hammer methods.

Water Treatment

The process of improving water quality to make it suitable for drinking, cooking, washing, cleaning, industrial, agricultural, recreational, and other uses.

Purpose of Water Treatment

To remove physical, chemical, biological, and radiological contaminants so water becomes safe for its intended use.

Contaminants

Undesirable physical, chemical, biological, or radiological substances present in water.

Sedimentation

A treatment method that removes suspended particles by allowing heavier materials to settle at the bottom.

Principle of Sedimentation

Uses gravity and still water to separate heavier suspended solids.

Coagulation

A process where alum is added to water to remove suspended particles and some color.

Alum (Hydrated Aluminum Sulfate)

The chemical commonly used as a coagulant during water treatment.

Aeration (Oxidation)

The exposure of water to air to improve taste and color while removing iron, manganese, and corrosiveness.

Benefits of Aeration

Improves taste, removes dissolved gases, oxidizes iron and manganese, and reduces corrosion.

Ozonation

A powerful oxidation and disinfection process using ozone to destroy microorganisms.

Ozone

A highly reactive gas produced by passing air or oxygen through high-voltage electrodes.

Purpose of Ozonation

To eliminate bacteria, viruses, and other pathogenic organisms.

Filtration

A treatment process that removes suspended particles, bacteria, and some color from water.

Slow Sand Filtration

A low-maintenance filtration method commonly used for rainwater that requires periodic cleaning.

Pressure Sand Filtration

A filtration system using pressure and sand filters, commonly used for swimming pools.

Backwashing

The cleaning process used in pressure sand filters by reversing water flow.

Diatomaceous Earth Filtration

A filtration method using powdered diatomite to remove suspended particles.

Diatomite

A naturally occurring siliceous sedimentary rock crushed into fine powder for filtration.

Pasteur Filter

A porous ceramic or unglazed porcelain filter commonly attached to faucets for household filtration.

Fine Filtration by Chlorination

A combined treatment that oxidizes iron and manganese while killing iron bacteria.

Activated Carbon Filter

A filter that removes dissolved gases, organic compounds, taste, and odor through adsorption.

Adsorption

The physical adhesion of contaminants onto the surface of a filtering material without chemical reaction.

Reverse Osmosis (RO)

A membrane filtration process that removes dissolved chemicals, minerals, suspended solids, and biological contaminants.

Semi-Permeable Membrane

A membrane that allows water molecules to pass while blocking many contaminants.

Desalination by Reverse Osmosis

The removal of dissolved salts from seawater using high-pressure membrane filtration.

Disinfection

The most important health-related water treatment process for destroying disease-causing organisms.

Chlorination

The standard disinfection method using chlorine to kill harmful microorganisms.

Alternative Disinfectants

Methods such as ultraviolet light, bromine, iodine, and heat treatment used instead of chlorine.

Free Available Chlorine

The amount of chlorine (1–2 ppm) needed to maintain bacteria at low levels in water.

Trihalomethanes (THMs)

Potential carcinogenic compounds formed when chlorine reacts with natural organic matter.

Sodium Hypochlorite

A chlorine solution commonly pumped into municipal water systems for disinfection.

Activated Carbon and Chlorine

Activated carbon filters can remove chlorine from treated water.