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American Association of State Highway and Transportation Officials.


Removal of material due to a frictional contact.

Abrasion Resistance

Ability of a material to resist the infliction of damage in the form of scratches, grooves and other minor imperfections.


A substance added in a small amount to enhance a material property.


Ingredients added during mixing; often in construction to aid workability of concrete, mortar or grout.

Aerial sewer

An unburied sewer (generally sanitary type), supported on pedestals or bents to provide a suitable grade line.


Presence of unreacted or free oxygen (02).


A property of effluent which favors the corrosion of its conveying structure.


The capacity to neutralize acids; a measure of the buffer capacity. The major portion of alkalinity in natural waters is caused by (1) hydroxide, (2) carbonates, and (3) bicarbonates.


An oxide of aluminum.


Able to live and grow where there is no oxygen.

Annular filler

Material for grouting the annular space between the existing pipeline and the lining system.


Free space between existing structure and any lining.


American National Standards Institute, Inc.


Large pipe or conduit to convey water from distant source.


Pertaining to water; an aqueous solution is a water solution.


American Society of Civil Engineers.


A valuable resource.


American Society of Testing and Materials, technical organization formed for the development of standards on characteristics and performance of materials, products, systems and services, and the promotion of related knowledge.

Available Water

Water necessary for the performance of work, which may be taken from the fire hydrant nearest the worksite, given conditions of traffic and terrain which are compatible with the use of the hydrant for performance of work.


American Water Works Association.



The vertical section in a manhole between the cone and the benchwall.


The slab structure which supports a manhole.

Benching or bench

The floor of a manhole into which the channel is set; the bench is raised so that it can drain to the channel.


The offer or process of the bidder submitted on the prescribed form setting forth the prices for the work to be performed.


A hard or semi-hard asphaltic residue; often used in construction as a waterproof/barrier layer.

Bituminous (coating)

Of or containing bitumen; as asphalt or tar.


Biological Oxygen Demand; a measure of the need for oxygen by organic processes.

Branch sewer

A sewer into which at least two sanitary, combined or stormwater sewers connect.


An amount of money needed or allocated for a specific use.

Building combined sewers

A small diameter pipe that conveys both wastewater and stormwater from a single property to a combined sewer.

Building sanitary drain

A small diameter pipe that conveys wastewater from a single property (e.g. domestic home) to a sanitary sewer.

Building Sewer

The conduit which connects building wastewater sources, to the public or street sewer, including lines serving homes, public buildings, commercial establishments, and industry structures. In this specification, the building sewer is referred to in two sections. (1) the section between the building line and the property line, frequently specified and supervised by plumbing or housing officials; and (2) the section between the property line and the street sewer, including the connection thereto frequently specified and supervised by sewer, public works, or engineering officials (Referred to also "building connection,' "service connection," or "lateral connection").


An arrangement of pipes and valves whereby the flow may be passed around a hydraulic structure or appurtenance. Also, a temporary setup to route flow around a part of a sewer system.

Bypass Pumping

The transportation of sewage which flows around a specific sewer pipe/line section or sections via any conduit for the purpose of controlling sewage flows in the specified section or sections without flowing or discharging onto public or private property.



A sum of money used to implement projects.

Cast iron (CI)

Sewer pipe material, sometimes provided as ductile cast iron.

Catch basin

A small buried structure to divert overland stormwater flow into sewer flows.


A geographical area draining to a sewer or receiving water.


Closed circuit television used to carry out internal inspection and survey of pipelines.

Centrifugal lining

A technique for applying a lining of cement mortar by rotating a spray head which is conveyed through a pipeline or manhole.

Change Order

A written order to the contractor authorizing an addition, deletion or revision in the work, within the general scope of work of the agreement, authorizing an adjustment in the agreement price or agreement time.


A prepared flow route within the bench of a manhole that conveys the incoming flow to the downstream pipe.

Chemical grouting

Method for the treatment of the ground around a shaft or pipeline, using non-cementitious compounds, in order to facilitate or make possible the installation of an underground structure.

Chemical resistance

Ability to render service in the transport of a specific chemical for a useful period of time at a specific concentration and temperature.


The small vertical section between a manhole frame and cone which is built from brick, masonry or concrete adjusting rings.


Cast Iron Pipe


Cured In Place Pipe; a rehabilitation technique whereby a flexible resin-impregnated tube is installed into an existing pipe and then cured to a hard finish, usually assuming the shape of the existing pipe.


Around the inner surface of a circular pipe cross section.

Closed-Circuit Television Inspection (CCTV)

Inspection method utilizing a closed circuit television camera system with appropriate transport and lighting mechanisms to view the interior surface of sewer pipes and structures.


A scientifically based factor that is taken into account during calculations.


A barrier built within the effluent so as to form an enclosure from which the effluent is pumped to permit free access to the area within.


Critical failure of a pipeline when its structural fabric disintegrates.

Collection system

A network of sewers which serves one or more catchment areas.

Collector sewer

A sewer located in the public way collects the wastewaters discharged through building sewers and conducts such flows into larger interceptor sewers and pumping and treatment works.

Combined sewer system

A single network of sewers designed to convey stormwater as well as sanitary flows.


The densification of a material by means of mechanical manipulation.


A measure of the ability of a solution to carry an electrical current. conductivity varies both with the number and type of ions the solution carries.


The section between the top of a manhole wall and chimney or the frame. The diameter of the manhole is reduced over the cone section to receive the frame. The cone section may be concentric or eccentric.


The gradual reduction in the volume of a mass resulting from an increase in compaction.


The person, firm or corporation with whom the owner has executed the agreement.


For brick manholes this term is sometimes used in place of cone, and indicates the gradual reduction in diameter by indenting brick.


The destruction of a material or its properties because of a reaction with its (environment) surroundings.

Corrosion Rate

The speed (usually an average) with which corrosion progresses.

Corrosion Resistance

Ability of a material to withstand corrosion in a given corrosion system.


The lid at the top of the manhole which can be removed when access to the interior of the manhole is required.


Fracture lines visible around the circumference and/or along the length of a sewer structure.


The number of persons required for the performance of work at a site as determined by the contractor in response to task difficulty and safety considerations at the time or location of the work.

Critical sewers

Sewers with the most significant consequences in the event of structural failure.


Pipeline installation in which the primary purpose is to provide one or more passages beneath a surface obstruction.


(1) Top of pipe segment, or (2) The highest elevation within a pipe.


Combined Sewer Overflow; a hydraulic relief point within combined sewer systems designed to discharge excess flows during wet weather to receiving waters.

Cured-in-place pipe (CIPP)

A lining system in which a thin flexible tube of polymer or glass fibre fabric is impregnated with thermoset resin and expanded by means of fluid pressure into position on the inner wall of a defective pipeline before curing the resin to harden the material. The uncured material may be installed by winch or inverted by water or air pressure, with or without the aid of a turning belt.

Coefficient of Thermal Expansion and Contraction

The fractional change in length of a material for a unit change in temperature.


Data logger

A device used to electronically record inspection data.


Accumulation of material consisting of organic (human waste, food wastes, etc.), (sand, gravel, wood, etc.), grease or roots.


The gradual decay of a sewer network accelerated by the negligence of effective maintenance.


Any method used to lower the water table in the vicinity.


Ductile Iron Pipe.

Discharge point

The point where the flows in a sewer are discharged to.


Modifying the normal wastewater flow to allow access to some specific sewer structure; often includes bypass pumping.

Double ring brick sewer

A brick sewer which consists of two layers of bricks.

Drop manhole

If the upstream pipe is at a greater elevation than the manhole invert then two inlet connections to the manhole are made. One is through the wall at the same grade as the upstream pipe, the other is at the invert so to direct flows through the channel. The invert connection is made by incorporating a pipe drop in the upstream pipe. The pipe drop may be outside or inside the manhole.


Dry Weather Flow; is the base flow in a sewer prior to rain induced flows.



A liberty, privilege, or advantage without profit which the owner of one parcel of land may have in the hand of another. In this agreement, all land, other than public streets, in which the owner has sewer system lines or installations and right of access to such lines or installations.

Easement Access

Areas within an easement to which access is required for performance of work.


A generic term used to indicate the relative strength of sewer flows; from stormwater to wastewater to industrial effluent, for example.

Elastic modulus

A measure of the stress buildup associated with a given strain.

Emergency repair

A repair that must be made while the main is pressurized, or flowing.


The surroundings or conditions (physical, chemical, mechanical) in which a material exists.


United States Environmental Protection Agency


Resin formed by the reaction of bisphenol and Epichlorohydrin.

Estimated Remaining Life (ERL)

A value determined by the inspectors based on experience, judgment, and guidelines within the manual that predicts the amount of time that a sewer structure will remain in a "fit-for-use" condition.


The leakage or discharge of flows being carried by sewers out into the ground through leaks in pipes, joints, manholes, or other sewer system structures; the reverse of "infiltrations".



US customary unit for measuring length. One foot equals 304.8 mm; or 0.3048 meters. (abbrev. ft).

Feet per second

US customary unit for velocity. One foot per second equals 304.8 millimeters per second; or 0.3048 meters per second. (abbrev. ft/s).

Flexural Modulus

The slope of the curve defined by flexural load versus resultant strain. A high flexural modulus indicates a stiffer material.

Flexural Strength

The strength of a material in bending expressed as the tensile stress of the outermost fibers at the instant of failure.


Sewage effluent.

Flow control

A method whereby normal sewer flows or a portion of normal sewer flows are blocked, retarded, or diverted (bypassed) within certain areas of the sewer collection system.

Flow reduction

The process of decreasing flows into a collection system or of removing a proportion of the flow already in a collection system.

Force main

A pipeline that conveys sanitary, combined or stormwater flow under pressure from a pumping (or lift) station to a discharge point.


Cracks visibly open along the length and/or circumference of an in placer sewer structure.


Geographical Information System (GIS)

A computer software system designed to store,manipulate, analyze, and print geographically referenced information.


Sieve analysis of aggregates.

Gravity sewer

A sewer that is designed to operate under open channel conditions (below pipe full capacity) up to a maximum design flow at which point it will become surcharged.


Glass fiber Reinforced Concrete; a rehabilitation lining.

Grease trap

Mechanism in a lateral that collects grease before it can reach a main line.


Subsurface water occupying the saturation zone from which wells and springs are fed. In a strict sense the term applies only to water below the water table.


(1) Material used to seal pipeline and manhole cracks; also used to seal connections within sewer structures. (2) A material, usually cement based, used to fill the annulus between the existing pipe and the lining; and also to fill voids outside the existing pipeline. (3) A material such as a cement slurry, sand or pea gravel that is pumped into voids.


Glass Reinforced Plastic, a family of rehabilitation linings. Often generically known as Reinforced Plastic Mortar (RPM) and Reinforced Thermosetting Resin (RTR).


A rehabilitation technique that employs steel reinforcement fixed to the existing sewer which is covered in concrete that is conveyed with air in a dry condition with water added through a ring within the nozzle.



High Density Polyethylene

Hydraulic cement - Waterplug

A cement based material that, when mixed with water, provides a very rapid setting plugging mortar for active water leaks in concrete and masonry.

Hydraulic Cleaning

Techniques and methods used to clean sewer lines with water e.g.: water pumped in the form of a high velocity spray and water flowing by gravity or head pressure. Devices include high velocity jet cleaners, and pressure-washer.

Hydrogen ion (pH)

Refers to acidity or alkalinity of water or soil. An ion is a charged atom or group of atoms in solution or in a gas. Solutions contain equivalent numbers of positive and negative ions.

Hydrogen Sulfide

An odorous gas sometimes found in sewer systems. Recognizable by a rotten egg odor. Chemical formula is H2S.



Infiltration/Inflow; this is the sum of all the extraneous contributions to the collection system.

Impact strength

The ability of a material to withstand shock loading.


Impenetrable. Completely resisting entrance of liquids.

In situ

Describes work on site; in the original place. For example, in situ concrete would differentiate cast in place concrete from precast concrete.

Inert material

A material which is not reactive nor mineral based, such as a plastic, epoxy, polyeurea, etc.


(1) Penetration of freshwater or groundwater into the sewer system through cracks, defective joints in the pipeline, and holes, or through lateral connections, manholes or inspection chambers. (2) All extraneous waters (storm water and ground water) which enter the wastewater collection system through various sources including, among others, pipe defects, defective service connections, manhole covers, roof leaders, and foundation drains.

Infiltration/Inflow (I/I)

The total quantity of water from both infiltration and inflow without distinguishing the source.


Water discharged into a sewer from sources on the surface.


An on-site representative responsible for inspection and acceptance, approval, or rejection of work performed as set forth in the specifications.

Interceptor sewer

A sewer that conveys flow from a trunk sanitary sewer or dry weather flow plus a small volume of stormwater from a trunk combined sewer to a wastewater treatment plant.

Internal corrosion

Corrosion that occurs inside a sewer structure because of the physical, chemical, or biological interactions between the structure and the effluent as opposed to forces acting outside the pipe, such as soil, weather, or stress conditions.

Internal erosion

Abrasion and corrosion on the inside diameter of the sewer structure due to the fluid that is being transported.

Internal inspection

Means of ascertaining the condition of pipelines and other sewer structures, either by visual inspection for man-entry size or by the use of remote control instrumentation.


(1) The lowest point on the pipe circumference; also the defined channel in the manhole platform that directs flow from inlet pipe to outlet pipe. (2) The inside bottom, lowest elevation, of a sewer pipe or manhole channel.



The means of connecting sectional lengths of sewer pipe into a continuous sewer line using various types of jointing materials. The number of joints depends on the lengths of the pipe sections used in the specific sewer construction work.



A stress unit equal to 1000 pounds.



A service line that transports wastewater from individual buildings to a main sewer line.


A rehabilitation process where a length of material is introduced to extend the life of the existing sewer.



Describes any trenchless technology process which requires an operative to enter a pipe or other sewer structure.


A structure that allows access to the sewer system.

Multiple ring brick sewer

A brick sewer that consists of three or more layers of bricks.


Notice to proceed

NTP, a written notice given by the owner to the contractor fixing the date on which the contract time will commence to run and on which contractor shall start to perform his obligations under the contract documents.



An outlet to a sewer system.


A public body of authority, corporation as partnership, or individual for whom the work in to be performed.



A broad term that can include pipe, casing, tunnels, ducts or channels.


A measure of the acidity or alkalinity of a solution. A value of seven is neutral.


A long tube of clay, concrete, steel, metal, wood, etc., for conveying wastewater, water, gas, oil or other materials.


Any of a variety of thermoplastic and thermoset material used in sewer construction (e.g., high-density polyethylene, polypropylene, PVC, fiberglass reinforced plastics, polyester felt reinforced pipe, epoxy and polyester mortars, etc).


An admixture to cement based materials to make a mix more fluid without the addition of more water.


To take out of public operation or ownership; to instigate private sector participation in the financing and/or operation and/or maintenance and/or ownership of public assets, such as treatment plants and collection systems, for example.


The entire construction to be performed as provided in the contract documents.


Pounds per Square Inch. US customary unit for pressure. One PSI equals 6.896 Kilonewtons per square meter.

Pump or pumping station

A structure containing pumps and associated piping, valves, and other mechanical and electrical equipment for pumping wastewater. Also called a lift station when it is used to lift wastewater from a low point to a higher pipe so that it can be transported by gravity.


Polyvinyl Chloride; a form of thermoplastic Pipe.




All methods for restoring or upgrading the performance of an existing wastewater system.

Reinforced concrete

Formed concrete with steel reinforcing material embedded in its walls. This product is commonly used for large diameter pipes.


Rectification of damage to the structural fabric of the sewer, or the reconstruction of short lengths, but not the reconstruction of a whole pipeline or system.


Construction of a new sewer, on or off the line of an existing sewer.


Sanitary sewer

A sewer that conveys the wastewater from two or more properties.


Wastewater transported in a sewer.


An underground pipe or conduit for transporting wastewater.

Sewer district

A sewer service area whose boundaries are established by a legal, political, or rate-making authority.

Sewer interceptor

A sewer which receives the flow from collector sewers and conveys the wastewaters to treatment facilities.

Sewer separation

Replacing a combined sewer with a separate sanitary sewer pipe and a storm sewer pipe. The sanitary sewer pipe flow is transported to the wastewater treatment plant and storm sewer flow is discharged directly to a drain or river, without treatment.

Sewer structure

Any portion of an industrial sewer system including pipeline segments, manholes, lift stations, wet wells, trap tanks, sumps and other structures.


A process where concrete or mortar is conveyed through a hose and pneumatically projected at high velocity onto a surface, as a construction technique.


(1) A process that describes the flaking, or slitting away of the surface layer. (2) The spontaneous chipping, fragmentation, or separation of a surface or surface coating.

Spiral wound

Generally PVC pipe lining material

SSO (sanitary sewer overflow)

An overflow, spill, release, or diversion of wastewater from a sanitary sewer system. SSOs do not include combined sewer overflows (CSOs) or other discharges from the combined portions of a combined sewer system.


When the sewer flow exceeds the hydraulic carrying capacity of the carrying structure.


Thermal Expansion/Contraction

The fractional change in length of a material subjected to a unit change in temperature.

Trunk sewer

A sewer that receives flow from lateral sewers or many tributary branches and sends the flow to an interceptor. These sewers serve a large territory, and generally only have a few connections, if any, to buildings or streets.


An underground conduit, often deep, which provides conveyance and/or storage volumes for wastewater.


Uniform Corrosion

Corrosion that results in an equal amount of material loss over an entire sewer structure surface.



Referring to a change after a tender is let



The liquid conveyed in sewer system.


Water Environment Federation.

Weir manhole

A manhole that contains a weir used to measure flow.

Wet well

A wastewater treatment receiving well typically within a Lift/Pump station.


Water industry operators of Australia


Water services association of Australia


Wastewater Treatment Plant.