Glossary for some common terms used in the water and/or waste water industries.

Activated Sludge
Oxygen dependent biological process that serves to convert soluble organic matter to solid biomass that is removable by gravity or filtration. Atmospheric air or pure oxygen is bubbled through primary treated sewage (or industrial wastewater) combined with organisms to develop a biological floc which reduces the organic content of the sewage.

Advanced Wastewater Treatment
Any treatment of sewage water that includes the removal of nutrients such as phosphorus and nitrogen and a high percentage of suspended solids.

Aerated Lagoon
A water treatment pond that speeds up biological decomposition of organic waste by stimulating the growth and activity of bacteria, with artificial aeration to promote the biological oxidation which is responsible for the degradation.

Aeration
The process of dissolving air in water or wastewater.  This is achieved by increasing the water air interface in order to promote the absorption of the air by the water.  In wastewater treatment, aeration increases oxygen content in the water.  Oxygen is needed by bacteria to break down dissolved or suspended organic materials.  In water treatment, aeration helps oxidize certain compounds into a form that settle in the water which can then be filtered out.  Aeration can help in the removal of gases in water, a process known as air stripping.

Aeration tank
A tank that is used to inject air into water.

Aerobic
A process that takes place in the presence of oxygen, such as the digestion of organic matter by bacteria in an oxidation pond.

Aggressive water
Water that is soft and acidic and can corrode plumbing, pipes and appliances.

Algae
Single- or multi-celled organisms that are commonly found in surface water, such as duckweed. They produce their own food through photosynthesis. The algae population is divided up into green algae and blue algae, of which the blue algae are very detrimental to human health. Excessive algae growth may cause the water to have undesirable odors or tastes. Decay of algae diminishes oxygen supplies in the water.

Ambient temperature
Is a common term to denote a certain temperature within enclosed space at which humans are accustomed. Room temperature is thus often indicated by general human comfort, with the common range of 10°C (39.446 °F) to 28°C (82.4 °F), though climate may acclimatize people to higher or lower temperatures.

Anaerobic
without air (where "air" is generally used to mean oxygen), as opposed to aerobic.

Bond Strength Testing
Involves determining the stress required to rupture a bond formed by an adhesive between two metal blocks.  Often the test involves the measurement of the shear and flexural bond strength of a bonding agent or a comparison of bonding agents under varying environmental conditions.  The test may compare the fractured surface produced to failure analysis results within the adhesive interphase region.

Bypass
The intentional diversion of a waste stream from any portion of a treatment or pretreatment facility; permissible under very limited circumstances delineated in the permit.

Chemical pollution
Introduction of chemical contaminants into a water body.

Chemical weathering
Involves the change in the composition of rocks, often leading to a 'break down' in its form. This is done through a combination of water and various chemicals to create an acid which directly breaks down the material.

Chlorine-contact chamber
The part of a water treatment plant where effluent is disinfected by chlorine.

Collector Sewer
A conduit that receives sewage and/or stormwater from two or more lateral sewers or other
branch conduits. A collector sewer has a minimum inside design diameter of 8”.

Combination Sewer
Is a sewer system that transports both stormwater and sewage.

CMOM (Capacity, Management, Operations & Maintenance)
The purpose for the EPA’s CMOM regulation is to reduce the occurrence of SSO’s (Sanitary Sewer Overflows)

CSO’s (Combined Sewer Overflows)
During periods of heavy rainfall or snowmelt, the wastewater volume in a combined sewer can exceed the capacity of the sewer system or treatment plant.  For this reason, Combined Sewer Systems are designed to overflow occasionally and discharge excess wastewater directly into nearby streams, rivers, or other bodies of water.

Cured in Place Pipe (CIPP) lining
CIPP is a jointless, seamless, pipe-within-a-pipe with the capability to rehabilitate pipes ranging in diameter from six to 96 inches and to negotiate bends. Pipe rehabilitation reduces infiltration and leaks in pipeline systems without digging.

Clarifier
A circular or rectangular tank used to remove solids in water or wastewater.

Collector sewers
Pipes to collect and carry wastewater from individual sources to an interceptor sewer that will carry it to a treatment facility.

Combined sewer
A combined sewer is a type of sewer system which provides partially separated channels for sanitary sewage and storm water runoff. This allows the sanitary sewer system to provide backup capacity for the runoff sewer when runoff volumes are unusually high, but it is an antiquated system that is vulnerable to combined sewer overflows during peak rainfall events.

Compressive strength
Is the capacity of a material to withstand axially directed pushing forces. When the limit of compressive strength is reached, materials are crushed. Concrete can be made to have high compressive strength, e.g. many concrete structures have compressive strengths in excess of 7252 psi, whereas a material such as soft sandstone may have a compressive strength as low as 725 or 1450 psi.

Consent Decree
A consent decree (also referred to as a consent order) is a judicial decree expressing a voluntary agreement between parties to a suit, especially an agreement by a defendant to cease activities alleged by the government to be illegal in return for an end to the charges. A consent decree can be either interlocutory or final. The former is given on some plea or issue arising in the cause which does not decide the main question; the latter settles the matter in dispute, and a final decree has the same effect as a judgment at law. Once entered, a consent decree is binding on the consenting parties and cannot be reviewed except on a showing that the consent was obtained by fraud or that the decree was based on mutual error or a failure of consent.

Contaminant
Any foreign component in a substance, for example in water.

Conventional sewer systems
Systems that were traditionally used to collect municipal wastewater in gravity sewers and convey it to a central primary or secondary treatment plant, before discharge on receiving surface waters. single-cell organisms, that reproduces by fission of spores.

Cooling tower
These are heat removal devices used to transfer process waste heat to the atmosphere. Cooling towers may either use the evaporation of water to remove process heat and cool the working fluid to near the wet-bulb air temperature or rely solely on air to cool the working fluid to near the dry-bulb air temperature. Common applications include cooling the circulating water used in oil refineries, chemical plants, power plants and building cooling. The towers vary in size from small roof-top units to very large hyperboloid structures (as in Image 1) that can be up to 200 metres tall and 100 metres in diameter, or rectangular structures (as in Image 2) that can be over 40 metres tall and 80 metres long. Smaller towers are normally factory-built, while larger ones are constructed on site.

Corrosion
Means the breaking down of essential properties in a material due to chemical reactions with its surroundings. In the most common use of the word, this means a loss of electrons of metals reacting with water and oxygen. Weakening of iron due to oxidation of the iron atoms is a well-known example of electrochemical corrosion. This is commonly known as rust. This type of damage usually affects metallic materials, and typically produces oxide(s) and/or salt(s) of the original metal. Corrosion also includes the dissolution of ceramic materials and can refer to discoloration and weakening of polymers by the sun's ultraviolet light.

Creep Testing
This test method is used to determine a sample's creep properties when subjected to a prolonged tensile or compressive load at a constant temperature.  The rate of deformation of a sample to stress at a constant temperature is known as the creep rate.  It is the slope created by the creep v. time.  Creep generally occurs at elevated temperatures, so it is common for this type of testing to be performed with an environmental chamber for precise heating/cooling control.  Temperature control is critical to minimize the effects of thermal expansion on the sample.  Creep is generally divided into three stages:

• the primary creep starts at a rapid rate and slows with time;
  the secondary creep has a relatively uniform rate;
  the tertiary creep has an accelerated creep rate and terminates when the material breaks or ruptures

If creep recovery is measured, the test will determine the stress-relaxation - the rate of decrease in deformation that takes place when the load is removed.  Creep is sometimes referred to as stress relaxation testing.

Culvert
Is a conduit used to enclose a flowing body of water. It may be used to allow water to pass underneath a road, railway, or embankment for example. Culverts can be made of many different materials; steel, polyvinyl chloride (PVC) and concrete are the most common. Formerly, construction of stone culverts was common.

Design life
The Design life of a component or product is the period of time during which the item is expected by its designers to work within its specified parameters; in other words, the life expectancy of the item.

Density
The weight of a substance divided by its volume.

Digester
A closed tank for wastewater treatment, in which bacterial action is induced to break down organic matter.

Direct run-off
Water that flows from the ground surface directly into streams, rivers, and lakes.

Diversion Manhole
A combined sewer manhole constructed with a regulating device to allow a desired quantity of wastewater to pass to the treatment plant. The excess flow is diverted into another conduit.

Discharge
Flow of surface water in a stream or canal.

Drop Connection
A vertical connection that is constructed with or added to a manhole to provide a controlled means of passing flow from a shallow sewer to a deeper sewer.

Elongation Testing
The increase in a sample's gauge length measured after or at rupture divided by the sample's original gauge length is referred to as elongation. The greater the elongation, the higher the ductility of the material. Elongation cannot be used to predict the behavior of materials subjected to sudden or repeated loading.

Epoxy
Is a thermosetting epoxide polymer that cures (polymerizes and crosslinks) when mixed with a catalyzing agent or "hardener". Most common epoxy resins are produced from a reaction between epichlorohydrin and bisphenol-A.

FRCL – Fiber Reinforced Cement Liner
A cured-in-place, monolithic fiberglass reinforced Calcium Aluminate or Portland cement liner.  Typically used for waterproofing wastewater structures.  FRCL’s can be applied as an underlayment (profilier) prior to spraying or placing a topcoat material, i.e.:  polyurethane or epoxy.

Flexural Modulus
The ratio, within the elastic limit, of the applied stress on a test specimen in flexure, to the corresponding strain in the outermost fibers of the specimen.

Flexural Strength Testing
Flexural testing is used to determine the flexure or bending properties of a material. Sometimes referred to as a transverse beam test, it involves placing a sample between two knife-edge points and initiating a load at the midpoint of the sample. Maximum stress and strain are calculated on the incremental load applied. Results are shown in a graphical format with tabular results including the flexural strength (for fractured samples) and the yield strength (samples that did not fracture).

Flow Monitor
A piece of equipment used to determine the hydraulic conditions of sanitary sewers.  Under various conditions Flow Monitoring can be used to determine Infiltration/Inflow (I/I) levels, calibrate dynamic hydraulic models, measure in-situ line capacity and detect bottlenecks within the system.

Force Main
The discharge pipe from a lift station or pumping stations which transports wastewater or storm water under pressure. A force main may be used to transport sewage up hills or under waterways and other depressions where gravity flow is not possible or practicable.

Green Product
A green or sustainable product is something made from renewable resources, which means they can grow back quickly and can be harvested with minimal harm to the environment.

Groundwater
Water beneath the surface of the ground contained in a saturated zone of a geologic stratum...Groundwater usually applies only to water below the water table and originates from infiltration. Service laterals are generally publicly owned and maintained to the curb line of improved public streets or the proposed standard location of the curb line in unimproved public streets and privately owned and maintained from the curb line to the structure.

Groundwater discharge
Ground water entering coastal waters, which has been contaminated by land-fill leachates, deep well injection of hazardous wastes and septic tanks.

Hydrostatic pressure
Usually measured as height x density, like 10 feet deep x 62.43 lbs / cubic foot (water)
= 624.3 lbs / sq.feet. or 624.3 lbs / sq.foot. / 144 sq.inches / sq.foot = 4.33 lbs. / sq.inch

Holiday Detector
Is also known as a porosity detector, pinhole tester, spark tester, jeep tester or jeeper. Holiday detectors are employed in the non-destructive detection and location of pinholes, holidays, bare spots or thin points in protective coatings applied for corrosion protection over metal or concrete (conductive) surfaces.

Impermeable
Not easily penetrated by water.

Inlet
Box-like underground concrete structure with openings to collect Stormwater runoff. Often an inlet is constructed as part of a curb and gutter system for passing stormwater runoff to a drain or sewer, and for separating debris and sediments from the stormwater.

Intercepting Sewer
A sewer that receives sewage from a number of collector and truck sewers and specific, limited quantities of wastewater from combination sewers through diversion structures and conveys that wastewater to a point for treatment or disposal.

Laminate
A laminate is a material constructed by uniting two or more layers of material together. The process of creating a laminate is lamination, which in common parlance refers to the placing of something between layers of plastic and sealing them with heat and/or pressure, usually with an adhesive.

Lateral Sewer
A conduit that receives sewage or stormwater from residential, commercial or industrial structures and discharges into a public collector sewer.

Lift Station
A facility that pumps wastewater or stormwater from a deep sewer to a shallow sewer in order for it to continue to be transported by gravity flow. A lift station has a very short force main.

Manhole
Is the top opening to an underground utility vault used to house an access point for making connections or performing maintenance on underground and buried public utility and other services including sewers, telephone, electricity, storm drains and gas. It is protected by a manhole cover, a (usually metal) plug designed to prevent accidental or unauthorized access to the manhole. Manholes are usually outfitted with metal or polypropylene steps installed in the inner side of the wall to allow easy descent into the manhole.

Mixture
Various elements, compounds or both, that are mixed.

Municipal Sewage
Liquid wastes, originating from a community. They may have been composed of domestic wastewaters or industrial discharges.

Municipal Sludge
Semi liquid residue that remains from the treatment of municipal water and wastewater.

Non-Potable
Water that is unsafe or unpalatable to drink because it contains pollutants, contaminants, minerals or infective agents.

Outfall Sewer
A sewer, storm drain, or other conduit that extends to the point, location, or structure where wastewater or drainage discharges.

Parts per Million
Expressed as ppm; a measure of concentration. One ppm is one unit weight of solute per million unit weights of solution. In water analysis the ppm is equivalent to mg/l.

Permeability
The ability of a medium to pass a fluid under pressure.

pH
Is the measure (on as scale of 1 to 14) of the acidity or alkalinity of a solution.

Physical Weathering
Breaking down of 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.

Pollution Reduction Facility (PRF)
A facility specifically designed and constructed to remove pollutants from stormwater runoff. Common pollutants include sediment, heavy metals, and plant nutrients. These facilities generally include native vegetation and wetland plants and provide passive treatment with natural processes.

Polyurea
Polyurea can be defined as the result of a chemical reaction between an isocyanate and an amine. In polyurea coating terms, this is generally a reaction between an MDI and HDI pre-polymer with amine-terminated resins. This is the formally excepted definition by the PDA.

Polyurethane
Commonly abbreviated PU, is any polymer consisting of a chain of organic units joined by urethane links. Polyurethane polymers are formed by reacting a monomer containing at least two isocyanate functional groups with another monomer containing at least two alcohol groups in the presence of a catalyst.

Polyurea/Polyurethane Hybrid
Polyurea/Polyurethane hybrid formulations can be defined as the result of a chemical reaction between an isocyanate and a mixture of polyol and amine reactants. These formulations generally provide an “intermediate” polyurea that displays many of the same properties of a polyurea. However, hybrid formulations can also display some of the negative problems associated with polyurethane chemistry. In coatings formulation, hybrids generally contain a polyether/polyester polyol and a primary amine resulting in a chemical backbone comprised of amine and hydroxyl functionality. Polyurea/polyurethane hybrids are normally associated with use on “non-critical” items that generally do not require immersion or extreme temperature conditions for application. Some examples of these applications include sprayed-in truck bed linings and balcony deck coatings.

Polyester Resin
A thermosetting or thermoplastic synthetic resin made by esterification of polybasic organic acids with polyhydric acids; examples are Dacron and Mylar; the resin has high strength and excellent resistance to moisture and chemicals when cured. It is used to manufacture millions of different products world wide and is often combined with fiberglass cloth to provide extra strength in the finished product.

Potable water
Water that is safe for drinking and cooking.

Pressure sewers
A system of pipes in which water, wastewater, or other liquid is pumped to a higher elevation.

Primary wastewater treatment
In primary treatment, the influent sewage water is strained to remove all large objects that are deposited in the sewer system, such as rags, sticks, tampons, cans, fruit, etc. This is most commonly done with a manual or automated mechanically raked bar screen. The raking action of a mechanical bar screen is typically paced according to the accumulation on the bar screens and/or flow rate. The bar screen is used because large solids can damage or clog the equipment used later in the sewage treatment plant. The solids are collected in a dumpster and later disposed in a landfill.

Public water system
An entity that provides "water for human consumption through pipes or other constructed conveyances to at least 15 service connections or serves an average of at least 25 people for at least 60 days a year.

Pumping Stations
Are facilities including pumps and equipment for pumping fluids from one place to another. They are used for a variety of infrastructure systems that many people take for granted, such as the supply of water to canals, the drainage of low-lying land, and the removal of sewage to processing sites.

Raw Sewage
Untreated wastewater and its contents.

Raw water
Is water taken from the environment, and is subsequently treated or purified to produce potable water in a water purification works. Raw water should not be considered safe for drinking or washing without further treatment.

Relief Sewer
A sewer designed and constructed to provide additional capacity to an existing sewer (relieve) that does not have adequate capacity to meet peak flow demands.

Reclaimed water
Sometimes called recycled water, is former wastewater (sewage) that has been treated to remove solids and certain impurities, and then allowed to recharge the aquifer rather than being discharged to surface water. This recharging is often done by using the treated wastewater for irrigation. In most locations, it is only intended to be used for nonpotable uses, such as irrigation, dust control, and fire suppression, and there is controversy about possible health and environmental effects for those uses. In some locations (not in the United States), it is given more advanced treatment and is used indirectly for drinking.

Runoff
That portion of precipitation that flows away (discharged) from an area.

SCP
Sprayroq Certified Partner

Sanitary Sewer
A sewer that carries liquid and waterborne wastes from residences, commercial buildings, industrial complexes, and institutions. Surface water, stormwater, and groundwater are not intentionally admitted.

SSO’s (Sanitary Sewer Overflows)
This is a discharge of untreated, raw sewage into local waterways.

Sedimentation Manhole
Manhole structure that functions as a small settling basin to settle out incoming sediments that are transported with runoff before discharging to a sump, pollution reduction facility, or other point.

Separate sewer
A sewer system that carries only sanitary sewage; no storm-water runoff. When a sewer is constructed this way, wastewater treatment plants can be sized to treat sanitary wastes only and all of the water entering the plant receives complete treatment at all times.

Sewer
Is a type of underground carriage system for transporting sewage from houses or industry to treatment or disposal. In some areas, sanitary sewers are separate sewer systems specifically for the carrying of domestic and industrial wastewater, and are operated separately and independently of storm drains, which carry the runoff of rain and other water which wash into city streets.

Sewage
Is the mainly liquid waste containing some solids produced by humans which typically consists of washing water, feces, urine, laundry waste and other material which goes down drains and toilets from households and industry. It is one type of wastewater and is a major actual or potential source of pollution, especially in urban areas.

Smoke test
A smoke test is used to find the location of breaks in the sewer line which allow storm water or groundwater infiltration.  Smoke tests can also be used to find illegal sewer hookups.

Storm Sewer
A conduit intended to carry stormwater, surface runoff, street drainage, and groundwater. Sewage is not intentionally admitted. Culverts are short lengths of storm sewer, open on both ends, used with surface or open channel drainage systems.

Stormwater
Is a term used to describe water that originates during precipitation events. It may also be used to apply to water that originates with snowmelt or runoff water from overwatering that enters the stormwater system. Stormwater that does not soak into the ground becomes surface runoff, which either flows into surface waterways or is channeled into storm sewers.

Storm sewer (U.S.), stormwater drain (Australia and New Zealand) or surface water system (UK) Is designed to drain excess rain and ground water from paved streets, parking lots, sidewalks, and roofs. Storm drains vary in design from small residential dry wells to large municipal systems. They are fed by street gutters on most motorways, freeways and other busy roads, as well as towns in areas which experience heavy rainfall, flooding and coastal towns which experience regular storms.

Sump
A manhole structure with perforated sidewalls, when configured with a sedimentation manhole, functions as an infiltration device for the disposal of stormwater runoff.

Tensile strength
Is the stress at which a material breaks or permanently deforms. Tensile strength is an intensive property and, consequently, does not depend on the size of the test specimen. However, it is dependent on the preparation of the specimen and the temperature of the test environment and material.

Treatment plant
A structure built to treat wastewater before discharging it into the environment.

Trunk Sewer
A principal sewer which collects the flow from two or more collector sewers, and generally has a minimum inside diameter of 10 inches.

Underflow Conduit
The pipe that carries limited flow from a diversion structure of a combination sewer to a trunk sewer and transported for treatment.

VOC
Are organic chemical compounds that have high enough vapor pressures under normal conditions to significantly vaporize and enter the atmosphere.

Wastewater
Is any water that has been adversely affected in quality by anthropogenic influence. It comprises liquid waste discharged by domestic residences, commercial properties, industry, and/or agriculture and can encompass a wide range of potential contaminants and concentrations. In the most common usage, it refers to the municipal wastewater that contains a broad spectrum of contaminants resulting from the mixing of wastewaters from different sources.

Wastewater infrastructure
Is a generic term to describe public works, piping and plant facilities that treat and distribute drinking water taken from the environment and deliver it for use to a community and also the cycle that manages and treats the wastewater that come back out of the community before its release back into the environment.

Wastewater Treatment Plant
A facility designed and operated to remove contaminates and pollutants form wastewater before discharging into the environment.

Wet Well
A chamber which is used for collecting liquid (sewage), and, to which the suction pipe of a pump is attached.