In the first stage of the sewage treatment plant, the solid waste is separated from the bulk sewage by gravitational settling and then incinerated.  The secondary phase includes the combination of the remaining liquid phase with active bacteria (seed).  The bacteria use the organic contaminants as cell material and an energy source and the result is the conversion of the contaminants to CO₂ and H₂O.  This process allows for bacterial growth, which form aggregates settling to the bottom as sludge.  This can be returned to the incoming waste flow to maintain the necessary biomass for decompostion.  The tertiary treatment involves the removal of nitrogen, a element critical for explosive algae and plant growth when in high concentrations. Once the tertiary treament is complete, the resulting water theoretically meets drinking water standards.  The process shown here is done to aerate the liquid and supply the bacteria with the necessary oxygen.

While most of the degradation has already occurred, this stage of the water treatment allows for the separation of sediment and floating macroparticles.

Shown here is a maze of canals that function to decrease the turbidity of the water.  Although the water is free of organic contaminants at this point, the standards of water remediation require the appearance of the water to be clear.

The water shown here is very clear.  The algae growth can be seen at a depth of about 10 feet.  Since algae need sunlight to grow, the growth shows the water is clear enough for sunlight to penetrate to the bottom of the canal.  From here the water will be aerated and discharged into Stony Brook.