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Learn It!

Dirty Words

Advanced Primary Treatment: So much for "Dirty Words" these three really make things clean! Chemicals called "polymers" are added to wastewater to help waste particles clump together in large enough chunks to settle out.

Biosolids: This is one of our favorite words because it is so fun to say. Try it now. Say Biosolids. Biosolids are processed waste, which can be used for beneficial reuse, such as fertilizer or covering trash at a landfill.

Cogeneration: The making of electrical and thermal energy.

Illustration of Collection System

Collection System: Wastewater is collected via a system of pipes made up of laterals, mains and trunk sewers. A lateral pipe connects your home to the City's main pipe, which connects to a larger trunk sewer before it reaches the Point Loma Wastewater Treatment Plant where it is cleaned and discharged into the ocean 4.5 miles offshore.

Digestion: Organisms break down sludge in the digestion process, creating as by-products methane gas, carbon dioxide, solid organic material and water. Sound similar to another process you know? It's true! You produce methane the same way, too!

Disinfection: During the third (or tertiary) stage of wastewater treatment process, chlorine is added to kill harmful organisms.

Effluent: Treated "cleaned" wastewater which flows out of a treatment plant.

FOG: Funky Odor Gone (bad). No, not really. FOG stands for Fats, Oil and Grease, all of which should be put in the trash not down the drain.

Illustration of Grit Chamber

Grit Chamber: Tank in which the flow of wastewater is slowed, allowing heavy solid materials such as pebbles, sand, coffee grounds and eggshells to sink to the bottom.

Influent: Untreated wastewater when it flows into a treatment plant.

Influent Screens: Wastewater filters through a screen, but large solid objects such as rocks, cans, plastic bags and sticks are stopped.

Inorganic Material: Nonliving things (e.g. rocks, toilet paper)

Lateral: Home (or business) sewer pipe that connects to the City's sewer main

Main: City's sewer pipe

Methane: Digester gas (also found in landfills, coal mines, swamps and the instestines)

Organic Material: Organic or living things (e.g. bacteria, tree roots, table scraps-stuff that Sparky isn't supposed to eat)

Polymers: Chemicals that can draw particles together like a magnet

Raw sewage: Untreated wastewater

Reclaim: To reuse

Reclaimed water: Water produced by a three stage treatment of wastewater for irrigation, landscaping and industrial uses (e.g. golf courses, cooling towers)

Photo of Sewer Pipe Scum

Scum: Scum is not your sister's name. Scum is the stuff floating on top of the wastewater made up of mainly fats, cooking oil, grease and shampoo.

Secondary Treatment: Biological treatment process in which bacteria (that's right, "bugs") consume organic matter, then settle out as sludge.

Sedimentation: Solid materials settle out of the wastewater into the sedimentation tanks.

Sewage (or wastewater): Sewage is your waste, your teacher's waste. It's the used water and added waste of a community which is carried away by toilet, sink and bathtub drains to the sewers.

Sludge: The solid waste material which settles out in the wastewater treatment process.

Tertiary (Third) Treatment: Anthracite coal is the tertiary treatment filter used by the Metropolitan Wastewater Department.