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Sewer treatment

The Plant Components

LIFT STATIONLift station, sewer

The Village lift station is located at the Japanese Gardens along the waterfront walkway.  The building is beautifully concealed by the garden design.  Housed inside the building is an elaborate pumping system, which collects the wastewater from town and pumps it through a force main to the sewer treatment plant.


This machine chews up any solids that have been flushed down the sink, toilet or drains. It is the first step in the digestion process – just like that of a human being.


The aeration tank is 20’ deep (2 stories). It is a complete-mix tank that uses oxygen to foster the growth of aerobic bacteria , which will be used to digest the organic materials in the effluent. 


In the lagoon tank, the aeration is slowed down. This allows the solids to settle down to the bottom where they become food for the aerobic bacteria. This material is called activated sludge.


A common problem in sewer treatment facilities is algae blooms.  Algae love to grow in sewer lagoons and flourish in the warm summer months when there is lots of sunshine.  Algae depend upon the sun and the process of photosynthesis to survive.  The floating lagoon is covered by plastic hexa-covers which prevent sunlight from penetrating the water surface and allowing the algae to grow.


Less oxygen is required as the sludge layer becomes more digested (almost non-activated grit, non-organic). The purpose of this lagoon is just to polish off the digestion process – to settle out the solids.

DAF TREATMENT PLANT – Dissolved Air Floatation SystemDAF Treatment Plant, sewer

Once most of the solids have settled out, a DAF treatment plant is used to remove organic solids. Alum and caustic soda are added to bind to organic materials. These particles then cling to fine bubbles and float to the surface. Squeegees are used to wipe the debris layer away, leaving clarified water. This water can then be treated with UV (Ultraviolet) light and chlorine.  

Upon completion of the treatment process, the effluent will be pool-water quality and can be used to irrigate green spaces (reclaimed water) or, before chlorination, can be discharged into the lake through the deep water outflow pipe.

Reclaimed pipes/hydrants are purple, in order to distinguish them from domestic water pipes, which are blue.