Industry Jargon Glossary
This glossary is designed to help engineers, contractors, owners, and operators better understand wastewater and precast concrete terms. Whether you’re designing a system, reviewing plans, or learning how treatment plants work, this resource explains key terminology in clear, practical language.
A
Anoxic Zones
Areas in a treatment process with very low or no dissolved oxygen where bacteria remove nitrogen compounds through denitrification.
Antimicrobial Admixture
A concrete additive designed to reduce bacterial growth that can damage concrete or cause odor and corrosion.
B
Base Riser
The riser of a base. In some cases for large structures we have to pour the riser first and then pour the base after to make a full structure (two-part pour) the "Base Riser" is referring to the riser itself
BOD (Biochemical Oxygen Demand)
A measurement of how much oxygen is required to break down organic matter in wastewater; a key permit parameter.
C
CB – Catch Basin
A precast drainage structure that collects stormwater runoff and directs it into underground piping.
Chlorination
The process of disinfecting treated wastewater using chlorine to kill harmful bacteria and pathogens.
Clarification
A treatment step where solids settle out of wastewater before disinfection and discharge.
Crystalline Waterproofing Admixture
A concrete additive that forms crystals within the concrete to block water intrusion and enhance durability.
D
De-chlorination
The removal of chlorine from treated wastewater before discharge to protect the environment.
Difference Between Casting a Ring & Setting It on Top
Casting the ring into the lid makes it part of the structure for strength and watertightness. Setting a ring on top means it is installed after and relies on sealing between components.
Discharge Limits
Regulatory water quality requirements that treated effluent must meet before being released to the environment.
E
EOD – End of Day
Construction or project documentation term marking the daily completion checkpoint or reporting cutoff.
Extended Aeration
A biological wastewater process where air is supplied for a long duration to stabilize wastes and reduce sludge production.
F
Flat Joint vs Tongue & Groove Joint
Flat joints connect with a smooth mating surface, while tongue-and-groove joints interlock for improved alignment and watertightness.
G
Grinder Pumps
Pumps designed to grind solids in wastewater so they can be pumped through smaller pipes.
H
Hydraulic Profile
The elevation and flow relationship of wastewater through each step of a treatment or pump system.
I
Invert
The interior elevation of the lowest point of the incoming and outgoing pipes.
Invert Channeling
A smooth channel formed in the base of the manhole that directs wastewater from the incoming pipe to the outgoing pipe, allowing unobstructed flow through the structure.
L
LS – Lift Station
A facility that pumps wastewater from a lower elevation to a higher elevation.
Lunch N' Learns
Educational sessions provided to engineers, owners, or contractors to share technical knowledge and product training.
M
MH – Manhole
A precast structure providing underground utility access for maintenance and inspection.
MIC (Microbial Induced Corrosion)
Concrete or metal deterioration caused by bacteria producing acidic environments (common in sewer systems).
O
Organic Loading
The amount of organic material (strength of wastewater) entering a treatment system, typically expressed in pounds of BOD.
P
Packaged Wastewater Treatment Plants
Factory-built, pre-engineered modular systems delivered to the site as complete treatment plants, including mechanical equipment and internal piping.
Permitting
The regulatory approval process required before constructing and operating a wastewater system.
Pretreatment
Initial treatment steps (such as screening or grit removal) to remove large debris before biological treatment.
R
Return Tops
A single-piece, monolithically cast concrete unit that combines the riser and top slab into one continuous structure.
Ring & Cover vs Flat Top
The ring and cover refer to the round cast-iron frame and lid assembly, while flat tops are the precast concrete tops that support and house the frame.
Ring & Cover- Top of Structure vs. Cast Into Lid
The cast-iron ring can either be embedded into the precast top during production or installed on top of the structure, allowing the frame to be removed if needed.
S
SCC (Self-Consolidating Concrete)
A highly flowable concrete mix that fills forms without vibration while maintaining strength and quality.
Sizing
Determining correct system capacity (flows, loading, pump requirements, tank size, etc.) to meet performance needs.
SOI – Schedule of Items
A project bid or contract list detailing materials, quantities, and pricing.
Sump
Low point in a structure where liquid collects before being pumped or drained.
Submersible Pumps
Pumps installed underwater inside wet wells to move wastewater.
T
Tertiary Filter / Tertiary Treatment
An advanced treatment step after secondary treatment to further polish effluent, often to meet strict permit limits.
TMDLs (Total Maximum Daily Loads)
Regulatory limits on how much pollution a water body can receive and still meet water quality standards.
Turn-Key
A complete, ready-to-operate solution that includes delivery, installation, startup, and all required mechanical equipment, internals, and piping.
Two-Part Pour
A precast method where concrete is poured in stages to create complex shapes, improve finish quality, and maintain strong monolithic performance.
W
Wet Well / Lift Station / Pump Station
A structure where wastewater collects and is pumped to the next stage of the system.
